Skyting

[Tad Eareckson]

1983/02
*
SKYTING NO.10
February 1983
*
1983/02-01

A personal note

Because I did not receive very many reports of your skyting experiences this month, I'm afraid that you are going to have to read another long article by me. Of course, I'm always ready and willing to talk about skyting. In fact, there are several topics I am wanting t write about right now. Topics such as cross-wind takeoffs, adverse yaw theory, and kiting techniques.

However, since I finally have a modern glider at my disposal (Remember my old-new Gemini in SKYTING NO. 7? Well it's repaired and fully airworthy now.), I would like to wait until I have more information about how the modern gliders react to these situations before writing about them. I have already had to make some subtle changes in my towing techniques when I use the Gemini instead of my old standard. But even though these changes are relatively minor, I still think it would be best to write articles based upon the performance of modern gliders instead of outdated information which would need to be revised almost immediately to be of use to most pilots.

So my article this month completely ignores skyting and other towing techniques and deals exclusively with conventional foot-launched hang gliding. Specifically, the article discusses how the laws of nature apply to hang gliding and hang gliding safety. Of course, the principles apply just as well to skyting as to conventional hang gliding, so the article is not all that inappropriate here in a skyting newsletter.

In fact, as a point of interest, this particular list of laws was first used in the development of the skyting tow system. Virgil, Red, and I used these laws as a guide to safety when we were learning to tow and to fly hang gliders all on our own. Every time one of use broke one of nature's laws, the rest of us would give him a hard time. We even made a game out of it - a contest to see who could go the longest without breaking any of the laws. For a while we even set up our own system of fines, requiring the guilty pilot to pay $1.00 to our "Kiting Kitty" so we would have the money available when mother nature demanded a payment.

But we soon stopped this practice because of accounting problems. Suppose a pilot crashes on takeoff and breaks a weak link. How much does he owe? $1, $2, $3, $4, or $5? Besides, it was getting too expensive for some of us because we were making too many beginner's mistakes.

Nevertheless, the list of laws did serve us well as an excellent guide to show that we were making mistakes even when we were not getting hurt. I'm convinced that havaing this list has helped us to become better pilots. (In fact, this list of laws is helping me today as I continually strive to become a safer pilot.) Perhaps it can help you too.

By the way, you may also be interested to know that Dan Johnson has asked me to do a series of articles on skyting in the next few issues of WHOLE AIR. The first of these articles, due to come out in March/April, describes several of the skyting systems which some of you developed and are now using. You may want to read the article and let me know if my perception of your towing technique is correct.

You may also want to subscribe to WHOLE AIR, since it is the first and only major hang gliding publication which seems to recognize that skyting exists and which plans to include articles on skyting in every issue.

But don't start worrying about my discontinuing this newsletter because skyting is finally beginning to receive coverage in other magazines. Sure, it would be nice to let someone else take over the responsibility of getting out a newsletter every month, but we still do need this publication as a means of mutual communication between those doing skyting research. So, with your help, we will continue sending out the SKYTING Newsletter as long as it is needed.

Thank you for your help.

Donnell Hewett
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1983/02-02

HANG GLIDING'S FIVE LAWS OF NATURAL REGULATION

by Donnell Hewett

Now that the FAA has finally begun to over-regulate the sport of hang gliding, a lot of pilots have a tendency to forget about that other regulatory system which has been in operation ever since hang gliding began and which is going to keep right on regulating the sport just as it has in the past, regardless of what the government does. To forget about this regulatory system is a "grave" mistake, for it is a very powerful organization and its methods of enforcement are very effective. Its authority even exceeds that of the Federal Government, and its rulings have a greater impact upon flying than even those of the FAA. It has a carefully selected set of laws which are impartially administered through a fair and speedy system of justice and imposes a full range of punishments designed specifically to fit the crime, such punishments range from a simple warning, to a slap on the wrist, to a fine, to confiscation of equipment, to being grounded, to imprisonment to a physical beating, to even execution. And its decrees are so final that even the United States Supreme Court cannot reverse its decisions. I am speaking, of course, about the system of regulation inherent in the laws of nature - natural regulation.

In fact, it is the fear and respect for these natural laws which is totally responsible for the success of "self-regulation" and for the outcry for more governmental intervention. Pilots who honor and respect the natural regulatory process generally feel that self-regulation is perfectly adequate for governing hang glider activities, while those individuals who feel that natural regulation is too harsh and inconsistent with their own personal concept of justice prefer that the government establish additional rules, another system of justice, and a different set of penalties.

One of the things that irritates a lot of people about natural regulation is the fact that nature will listen to no excuses. No amount of pleading, crying, threatening, rationalizing, or blame shifting will have any effect at all upon the judgement of nature. In nature's mind the situation is very clear: "You broke the law, you pay the penalty!"

Nature also clearly affirms that "Ignorance of the law is no excuse!" The result of breaking natural laws is exactly the same whether one is aware of the danger or not. In a very real sense nature seems to say: "I care not the reason why, you must either do or die!"

Because nature is so impersonal, a lot of people have gotten the false impression that the justice administered by nature is is completely void of any mercy. Yet, how many times have you done something that's really stupid - I mean something which you were certain nature was going to call you to account for - and through some kind of miracle, you escaped without any harm whatsoever. Perhaps you call it "dumb luck", or "an act of God", or "nature's mercy", the name does not matter, the effect is the same. Perhaps the reason we keep getting ourselves into trouble with nature is that we fail to recognize such "close calls" for what they really are: nature's "warning tickets" and "suspended sentences."

We would indeed be wise to heed these "warning tickets" which nature issues and to try a little harder to obey the laws which nature has established. But what are these laws, and how do they apply to hang gliding?

Well, actually, nature's hang gliding laws can be expressed in many different forms. For example, all of them could be condensed down into a single general principle such as "Don't goof up!" Or they could be spelled out in minute detail for every specific situation that could ever occur, such as, "Never fly a hang glider into a high voltage power line in such a manner that one leading edge touches the high voltage line and the other touches the wet ground while the pilot is suspended between them with one hand on each of the metal down-tubes in such a manner that the resulting electrical current passes through the cardiovascular system of his body."

But the single general principle in the first approach is to vague to be of much use, and the intricate details and the almost infinite number of specific examples in the second approach makes it too cumbersome to be of practical value. I, therefore, prefer to express nature's hang gliding laws in five parts, each part specific enough to be applicable. Although these laws are not mutually exclusive (they overlap quite a bit), they do seen to cover every situation which I, personally, have ever encountered.

FIRST LAW: ALWAYS FLY UNDER CONTROL.

This is by far the single most important natural law of hang gliding. In fact, the other four laws are simply corollaries of this general principle. When it comes to hang gliding, the name of the game in a single word is "CONTROL". It is utterly impossible to over emphasize this simple truth: NATURE DEMANDS THAT A PILOT MAINTAIN CONTROL OF HIS CRAFT AT ALL TIMES.

As long as a pilot is under control, nothing bad is going to happen (unless the pilot deliberately makes it happen, in which case he gets what he asks for). On the other hand, any pilot who, for any reason, permits himself to lose control of his aircraft is justly declared by nature to be an unfit pilot and appropriately punished for flying in that condition.

Admittedly it is sometimes difficult to tell when someone else is breaking this law (sometimes it look like a pilot is out of control when he isn't and vice versa), but the pilot, himself, knows whether or not he is breaking the law. (And, of course, nature also knows.)

Specifically, a pilot is under control when he and his glider are doing what he wants them to do. Any time a pilot finds himself in a situation that is not going the way he wants it to go - then he is out of control and he is breaking the first law of hang gliding. Even if he is able to regain control before something bad happens, he has still broken the law. (He just didn't get punished.)

Actually, nature is pretty forgiving about breaking this first law. The most common punishment is a suspended sentence. As a result, many pilots tend to lose their respect for the first law and begin to make it a habit to break the law without giving it a second thought. But this can be disastrous. Just as a person who habitually exceeds the speed limit on the highway will eventually get caught and forced to pay the full fine, so will the person who habitually breaks the first law eventually get caught and have to pay the full penalty assessed by nature. And the penalty for breaking this law can range anywhere up to the death penalty. So don't ever treat this law lightly, nature doesn't.

SECOND LAW: ALWAYS MAKE A GOOD TAKEOFF.

Let's face it, if you blow your takeoff, you've blown your flight. A good takeoff is such an essential part of having a good flight that when I originally listed the laws of natural regulation I left this one off. But a look at the list of hang gliding fatalities soon revealed that nature doesn't leave this law off of her list. In fact, whereas nature seems to be pretty forgiving about violations of the first law, she hardly ever overlooks violations of the second law. The consequences of failing to hook in, failing to pre-flight properly, stalling on takeoff, dropping a wing on takeoff, or losing one's footing on takeoff can range anywhere from a good scare to immediate execution. The usual result is a damaged glider, but all too often the result is death. Pilots would do well to keep this law in mind and make every effort to observe it on every occasion.

THIRD LAW: ALWAYS MAKE A GOOD LANDING.

Regardless of how well a pilot performs in the air, if he does not make a good landing, nature considers him to be incompetent and punishes him accordingly. Conversely, no matter how poorly a pilot may fly (even if he is out of control most of the time and breaks every other natural law of hang gliding) his chances of getting hurt are extremely small as long as he always makes a good landing. In this respect the third law is like the first, always obey it and you'll be all right.

But unlike the first law, where a warning is the most common penalty, the third law almost always extracts a payment when it is violated. Nature simply is not very forgiving when it comes to violations of the third law. Usually, though, the payment is light - something like a literal slap on the wrist or small fine for having the glider repaired. As a result, some pilots, particularly those with a tough skin or a fat bank account, tend to habitually violate this law. But the importance of this law should never be minimized. It is not uncommon for nature to confiscate a pilot's glider, imprison him in a hospital, or even put him in the morgue. In fact, nature seems to reserve the death penalty exclusively for those pilots who violate the third law. So if you intend to live very long, you'd better develop a habit of obeying the third law.

FOURTH LAW: ALWAYS AVOID OTHER OBJECTS.

It certainly does not take a genius to realize that a person flying a hang glider should not fly into a tree, fence, pole, power line, automobile, cloud, cliff, building, animal, human, dust devil, rotor, the ground, other aircraft, their wing tip vortices, or any other object or thing that a pilot could possibly encounter. In fact, nature considers such encounters to be so serious that she hardly ever overlooks them.

A pilot can usually regain control after losing it, he can frequently recover from a bad takeoff, and he can sometimes get by with a poor landing, but when he flies into another object, nature is going to make him pay something. Rarely does he get by with less than a broken glider, and the death penalty is not all that uncommon. So, once more, if you plan to keep on living, you better respect the fourth law of natural regulation and learn to obey it.

FIFTH LAW: NEVER EXCEED THE LIMITS OF YOUR EQUIPMENT.

Any time a pilot pushes his body, mind, emotions, skills, glider, instruments, accessories, or any other equipment beyond its strength or capabilities, or if he uses such things in a manner for which they were not designed or intended, nature will see that he is appropriately reprimanded. Like the fourth law, a violation of the fifth law is rarely overlooked by nature. Although there are cases (like breaking a weak link) which nature usually overlooks, in the vast majority of cases a violation of the fifth law usually results in some kind of repair bill, and there are other cases (such as flying into a thunder storm) which almost always end in execution.

Of course, the only way a pilot can consistently obey the fifth law is to continually check the condition of his equipment, making sure to replace or repair any part that is not in the best possible condition, and to make a personal rule to never fly unless the pilot, the glider, the weather, and all other factors are "perfect".

COMMENT

Notice that these laws of natural regulation are not really new. In fact they are quite obvious to almost everyone. Furthermore, it is true that pilots seldom violate any of these laws intentionally. Yet, time after time they are broken, and time after time the price is paid. Why? Because the pilot is simply not paying close attention to what he is doing and he has not developed the habit of always obeying these five laws of natural regulation.

Nature gives you a lot of probated sentences, and if you will, you can learn from them. But when nature does hand down a judgement, she will listen to no excuse and the decision is final. THERE IS NO APPEAL!

If you don't want to pay the fine, then don't break the law. For if you continue breaking the law, you will eventually get caught and have to pay the fine.

EXAMPLE

Perhaps the following dialogue will illustrate how Mother Nature treats a Careless Pilot who goes about breaking her laws:

Mother Nature: I hear you've been breaking some of my laws.

Careless Pilot: Uh, yes'm, but I didn't mean to. In fact, it really wasn't my fault at all.

MN: Perhaps you could tell me exactly what happened.

CP: Yes ma'm, you see, there I was, getting ready for a windy cliff launch, standing at the edge of the cliff, overlooking the beautiful valley far below. The magnificence of your wonderful creation was so exhilarating that I could not help but exclaim in my excitement, "All right!"

Well, my nose man - he was new at the job - well, he must have thought I meant for him to let go of the nose wires of the glider. And then, at that very same instant, you decided to throw a strong gust of wind my way.

Before I could do a thing, the glider was thrown up into the air and I found myself in a stalled position looking down on the launch pad with my glider's nose high and one wing low.

Well, I'm a very good pilot, you know, and I recognized the gravity of the situation immediately. So I pulled in on the control bar and shifted my weight to the proper side.

I just bearly missed the edge of the cliff on the way down, and suddenly I found myself rushing toward a group of trees located on the side of the mountain.

I pushed out hard on the control bar to miss the trees, but the excessive "g" loading on the glider caused one of the flying wires to break. The wing folded up, and I found myself tumbling through the air a few feet above the top of the trees. It was too late to throw my parachute, so I braced myself for the upcoming impact with the ground.

MN: I see, then, you didn't just break one or two of my laws, you broke all five of them: (1) you were flying totally out of control from beginning to end, (2) your takeoff was atrocious, (3) your landing could hardly be called a landing at all, (4) you failed to properly avoid the cliff edge, the trees, and especially the ground, and (5) you definitely exceeded the limits of your equipment.

I hope you realize that breaking even one of my laws is a very serious matter, and here you have gone and broken every one of them. Do you have anything to say in your own defense before I pass sentence?

CP: Yes, I do. I already told you that it wasn't my fault. I had no way of knowing that green-horn nose man was going to release my glider on the wrong signal, or that you were going to hit me with that strong wind gust at that very same instant. And even if I had known, there was absolutely nothing I could have done to prevent it.

MN: Not that it matters, but just what were the wind conditions at the time the gust hit?

CP: Uh, about 20 mph with gusts to 30. But I have handled wind conditions like that many times in the past. If fact, I would have been all right this time if only the glider's wire had not broken.

And that wasn't my fault, either. I want you to know that I pre-flighted my glider this time just like I have always done since buying it four years ago. And I'm not unfamiliar with my glider either - I've put more than 500 hours on this baby, many of them ridge soaring in the strong salty air along the rugged coast.

If that glider had been built a little better it wouldn't have broken. It's really the manufacturer's fault - or that of the HGMA certification program. After all, I couldn't have been pulling more than two or three g's when the wire broke, and a certified glider should certainly withstand that kind of force.

MN: Again, it doesn't really matter, but just for curiosity, why were you flying such an unsafe glider?

CP: Huh? Well, I didn't mean that the glider was all that unsafe. It's really been a pretty good glider and has withstood some pretty rough times. To be honest, I was surprised it broke this time. Besides, it was the only glider I had - really all I could afford. Actually, I was quite fortunate to get such a good glider at such a bargain price in the first place.

I'm not rich, you know. All my life I've been deprived of may of the necessities of life which other people just take for granted. I'm really just a victim of circumstances.

And if you are truly honest, you will have to admit that a large portion of my troubles were your fault. I wasn't the one who caused that wind gust, made the cliff so dangerous, put the trees there, or caused the ground to be so hard. You did.

MN: If it makes you feel any better, then go ahead and blame me for all your troubles, |Or anyone else, for that matter,| I really couldn't care less.

So far, everything you have said in your defense is totally irrelevant and immaterial. The fact remains that you were the pilot in charge, and as such I hold you, and you alone, totally responsible for violating my laws. And it is you who are going to be the one to bear the consequences.

You realize, of course, that the normal punishment for breaking all five of my laws at the same time is immediate execution.

CP: Gulp!

MN: However, I was planning on making to day one of my better creations, and I am not about to let the likes of you go and spoil it all. So I have decided to go easy on you this time.

CP: Oh, thank you ma'm.

MN: I therefore decree that both you arms, three ribs, and one leg be broken, and that you be given a blow to the head resulting in a mild concussion; that you be imprisoned for 30 days in the hospital and required to pay all the bills yourself; that when finally released from the hospital, you shall be denied the right to gainful employment for a period of 4 months and be grounded from flying a hang glider for a period of not less than 9 months; and, finally, that your hang glider and all of its associated equipment be impounded until you pay a fine of $785.39 to have it properly repaired.

CP: But -

MN: Now I hope that this unusually light sentence will not make you forget how really serious your crime has been. I am generally not so lenient toward those pilots who go about breaking my five laws. You should consider yourself quite lucky.

CP: But, wait a minute -

MN: There's no need to discuss this matter any further. My decision is final. There is no appeal. The sentence is to be carried out immediately. Case dismissed!

CRUNCH!
*
1983/02-03

HOOKED ON SKYTING

Dear Donnell,

Thank you, so much, for making tow hang gliding so enjoyable!

Your Skyting system has taken the work out of tow launching and has added an immeasureable amount of FUN!

As a woman pilot of 4 years, and having accumulated only 10 total hours of flying time, in 174 flights, I found myself being less and less attracted to tow launching, with our present Moyes technique.

Considering the local terrain, towing is the only way to increase our air time, without extensive traveling and much expense.

Since Bill, my husband, a 5 year pilot with 107 hours and 1,388 flights, knew of my sincere want of that flying time, he sent for our Skyting instructions and proceeded to follow them.

Two days ago, I had my first Skyting launch, behind a snowmobile, on a lake which had a 2 ft thickness of ice and a 3 - 4 inch blanket of snow.

The wind was about 5 mph and after a few anxious moments, I shook the kite, as a signal to Bill, to "GO!".

I found myself gently pulled up into the 25 degree air at the end of a 100 ft line, with just 5 or 6 steps.

"What? I'm flying? No!!! But, where's the moose of a glider I'm used to?! Where are the bulldog movements needed to handle his kite?!

Gone forever!

"My 185 sq. ft. Maxi SP is behaving like a whole new creation! Pinch me! Is this real?"

I went on to have 2 more fun-learning flights that day, and today, I extended my Skyting experience by 5 additional flights, on a 300 ft rope.

Gene, a friend of ours who is a 2 yr, 10 hr pilot, and had never towed before, now has 10 perfect Skyting launches and flights and recorded in his log book.

Bill, last summer, had upped his flight count with 4 Skyting flights behind our boat.

Two of the launches were running beach starts and the other 2 were deep-water. All 4 launches and flights went great and Bill was instantly and openly encouraged by your Skyting system.

With every flight, Bill, Gene and I have had no trouble maneuvering out of a lock-out situation, of which there have been many.

So, our careful experimenting and safety-minded learning will go on before, during and after each winter skyting day.

I'm looking forward to the tow rope being lengthened, which means gaining more altitude, therefore, longer flights and more airtime!!

I am hooked ... with sincere thanks to you!

Terry Cummings
Hoyt Lakes, Minnesota
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BRIDLE LOST IN THE SNOW
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1983/02-04

Dear Donnell,

I received my skyting set up from you. Thank you for your efforts. I had two short flights. On my first flight, the quick release tripped off. My second flight went good, but my driver turned around in the field without rolling up the rope. The quick release must have caught on something below the snow and broke the weak link so therefore we could not find the releases in the 6 inches of snow. I'm impressed with the skyting system. It feels close to the natural free flight.

Please send me a new bridle and quick releases.

Gregg Cairns
Innisfail, Alberta, Canada
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1983/02-05

Dear Gregg,

I was sorry to hear that you had lost your bridle, especially after only two flights. But I was happy to hear that you enjoyed the flights you did make on the skyting system.

To prevent losing your new bridle system, I suggest that you do like us. Instead of rolling up the line after every flight, simply disconnect it from the tow vehicle and drive over to the bridle end (or walk over and pick it up, if you prefer). (You can always find it by following the towline.) Then drag the towline back to take-off while holding the bridle in your hand. If the line snaggs hard enough to break the weak link, it will pull the bridle out of your hand ahd you will know to stop and investigate. (Actually, there is very little chance of it snagging because nothing is being drug except the straight towline.)

After you've had a chance to really test the skyting system, write me again and let me know what you think.

Donnell
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1983/02-06

SKYTING IN MISSOURI

Dear Donnell,

We haven't talked for a while but we are still skyting in St. Louis.

From what I read in the newsletter everyone seems to be having the same problems and discovering the same solutions that we are here in St. Louis, more or less.

I have described the bridle system in Cincinati, Ohio club as well as the Sacramento, California club. (We work closely with the Rolla, MO club.) Everyone seems eager to try the system because it promises safety. Most pilots, it seems, at one time or another got interested in towing and then gave it up because of horror stories or the expense involved with current commercial systems. Once I've shown them the simplicity and inherent safety of the system, the spark of interest becomes a glowing flame.

I described the problems with the "wild horse" release we had in a previous letter. We have since been working with two and three ring releases. (See Fig. 1 and 2.)

The three-ring release requires very little tension-to-release even at high loadings. The two-ring release requires more to release and may may be preferred by some. Using a "release pin" as described by Henry Wise (Skyting No.1) should prevent early release with either system.

Another change we have experimented with (also described by H. Wise, Skyting No. 9) is top releasing first, auto-releasing the bottom. The reason we did this was to remove the auto-release line from dangling in front of the pilot's face reducing the risk of several previously described hazards. We feed the release cord down the control bar through a couple of rings. Then the cord is terminated in a loop which goes over the pilot's wrist. (Fig. 3) There is enough freedom of movement to go from uprights to base tube and a simple flick of the wrist to the rear releases the bridle.

With this system we have been getting 600 ft on a 900 ft rope consistently before we run out of road.

We tow on a levy which is about 20 ft above the surrounding terrain. This makes our cross-wind takeoffs scarier than Bleep! Upwind tip will lift off, then the pilot and glider will slide off to the lee side precariously slipping along, hugging the slope of the levy until airspeed overcomes the rotor. It's a real experience!

To date we have towed the following gliders: Dove, Firefly, Raven, Comet, Meteor, Spirit, and Mosquito. I have noticed the overcontrol problem with both the Mosquito (wide nose angle, high aspect ratio, single surface) and Meteor/Comet (Floating crossbar, double surface). I attributed both problems to overcontrol on my part but I don't think it's just that. The Raven is a very sensitive ship and my observations have been that it has none of the tendencies of the others for overcontrol. I conclude there is more to it than a tilted earth with increased gravity.

It may be that towing in front of the C.G. causes some adverse yaw. This problem does not appear in "billow cruisers". I know someone will come up with a logical solution for all this. Mean while we will be moving the tow point back to the C.G. (Fig. 4).

We are building a tow rig for an Eagle after a design we obtained from Michigan pilots. They have been air-to-air towing with a three point bridle but are very interested in the skyting bridle. We should be operational for air-to-air by early spring.

One final note: I'll be moving to the Bay Area in California and giving up all this beautiful flat country, but you can be sure I'll continue to spread the word about Skyting wherever I am. I'm resigning as president of Gateway Hang Gliding Club so future newsletters should go to Dan Marcus of St. Louis.

Dennis R. Owen
Rock Hill, MO
+
Figure 1. Three ring release (seperated).

Eliminate this ring for 2 ring release
Nylon (Weak link cord size)
Brass eyelet
Nylon webbing
+
Figure 2. Three ring release (locked).

3 steel rings
progressively smaller
Coated cable or steel pin may be used for release.
Rubber bands may be used to hold in place when no tension.
Nylon webbing
+
Figure 3. Release cord arrangement.

Keel
Base tube
Tow line
Release
Release cord
+
Figure 4. Limiter cord arrangement.

Keel
Control Bar
Tow line
Limiter cord long enough to allow freedom at all but highest angles.
*
*

[Tad Eareckson]

1983/03
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SKYTING NO.11
MARCH 1983
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1983/03-01

ACCIDENTS ARE STILL HAPPENING

by Donnell Hewett

This issue of Skyting describes two serious skyting accidents which occurred recently. The first of these accidents resulted in a broken leg and a concussion, and the second accident resulted in a broken arm. The first accident occurred when some highly experienced hang gliding pilots were trying skyting for the first time. The second accident occurred when an experienced skyting pilot was pushing the frontiers-namely, when I tried kiting in conditions that were not quite kitable. That's right folks, I broke my arm in the skyting equivalent of the classic stalled take-off (followed by a ground loop).

To be honest, I find my own accident very embarrassing and can hardly face my friends and relatives. Particularly those who have warned me about the dangers of skyting. A lot of my friends have told me "Don't you think somebody's trying to tell you something. You know the next time, it might be your neck. After all, the third time's the charm." And I'm sure there are others who have disagreed with certain aspects of the skyting philosophy who will take this as evidence that land towing in general and skyting in particular is indeed as dangerous as they thought it was.

It is certainly embarrassing, if not unfortunate, that these accidents occurred just when skyting seemed to be gaining acceptance among the general hang gliding community. Many pilots who have previously refused to even consider the skyting alternative have recently begun to look at it seriously. I'm sure that these accidents will give them second thoughts. Yet, in my opinion, we are now entering the most dangerous period of skyting development. Namely, that period where a lot of pilots are beginning to recognize the potential safety of skyting before the details of skyting safety have been established and made available.

I have stated before, that my greatest fear about skyting is that pilots will start believing it is too easy and too safe and will start using it without proper training. This is why I have not advertised skyting in other publications or attempted to promote it more openly. Now that news of skyting has spread by word-of-mouth- throughout most of the hang gliding community, a lot of pilots are renewing their interest in towing and some of these are attempting to tow who previously stayed away from this area of hang gliding. So although these accidents are unfortunate, from the point of view of the ones who experienced them, perhaps they are fortunate from the point of view of the hang gliding community to be appearing at this time, because they remind us of the importance of caution during this period of skyting development.

The major problem with having broken my arm is the fact that I cannot write (it's my right arm and I am right handed) nor am I able to type up this newsletter. Fortunately my wife has graciously consented to help me with this endeavor by helping me put out the newsletter. Because of my broken arm, this newsletter and possibly the next couple, will be shorter than normal. Sorry, but that's the way things are.

You can help me considerably, if you send me material to be included in the next few newsletters, so that I personally do not need to write as much. I know that spring flying is coming up, but then I'm sure that there's many things that happened last summer, fall and winter that you could write about that would be of interest to other pilots. Again, with your help, we can keep this newsletter going.
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SKYTING MAY REVITALIZE AN INACTIVE HG CLUB
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1983/03-02

Dear Donnell,

I have just finished reading Skytings (1-9) at the request of a very enthused Larry Flick. I must say I'm very impressed with your Skyting system.

Larry and I had formed a club several years ago to help locate and secure flying sits in our area of the state since our only other flying site a 400ft dune was 4 and 1/2 hours away, one way, and during the good flying season we make the trip at least every other week end. Unfortunatly our area is very flat, and with out a site our local club broke up. Though Larry and I kept looking for a way to bring flying to our area. We never seriously considered towing because of its inherent dangers and I had been flying a powered easy riser and found powered flying just wasn't as much fun as free flying. Then Larry started getting excited about air to air towing as a few of the pilots in our area were beginning to practice this form of towing, but the traditional towing dangers were still there. Then along came skyting and Larry and I believe it is the answer to our problems.

So please find enclosed $75 for your Skyting equipment and $50 for 1,000 ft of towline.

We are aware of the fact that Skyting is still experimental and to advance Skyting to an even higher level of safety than it has already achieved, an open exchange of ideas and experiences through your news letter is very important.

We are looking forward to hearing from you, and working our way up to the Skyting level to be ready for some thermalling by spring.

We hope we can revive our club, the Michigan Ultralight Gliding Assoc. and bring the fun of flying to a great many people thanks to Skyting.

Harold Austin
Royal Oak, MI
*
1983/03-03

Dear Harold,

The material you requested is enclosed, except for the 1000-ft of tow line, which I did not currently have in stock. I have ordered additional towline from my supplier and will send you your portion as soon as I get it.

I hope that the material enclosed is what you had in mind. When you said you were including $75 for "skyting equipment", I did not know exactly what you wanted. Therefore, I sent you one of each item listed in the Skyting No.1 Supplement. In addition to this material, we now have a limited supply of used dragchutes, which can be obtained for $15 each.

I normally do not ship equipment to individuals who do not subscribe to the Skyting Newsletter and who do not have the back issues of Skyting available for reference. But in your case, you said that you have read the back issues of Skyting and I assume that future issues are available through Larry Flick. But if you are really serious about keeping channels of communication open between you and me, I would think you would want to have your own subscription to the Skyting Newsletter. It only costs $10 per year.

Please keep us informed about your Skyting progress. We are always interested in hearing about how others are doing.

Good luck in reviving your club, and good skyting.

Donnell
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1983/03-04

A BROKEN LEG IN CALIFORNIA

Donnell,

The basic method we were using was to open the pay out winch until the truck reached take off speed which was 25-mph in no wind for a pilot that weighed about 150 lbs. After about 1,000 feet of line was extended the winch operator would then "come on" the winch which basically resulted in a "pop start". Then the driver would increase the speed as fast as possible to 30-mph or excessive slack would happen in the towline. At about 400' most pilots released the keel attachment of the bridle to get the uncomfortable line out of the way and make pitch control slightly easier.

The accident happened when the start may have been a little stronger than normal with a 1st time tow pilot. The pilot may have lost the control bar on launch (disagreement among witnesses) resulting in a steep climb. The bridle stretched enough to trip the automatic release at the keel resulting in a straight up climb. Then the perlon bridle broke with the glider in a straight up vertical climb with no air speed. At this point the pilot pulled his body as far forward as possible resulting in a forward rotation of the glider with no airspeed. The glider rotated to a straight down attitude and hesitated at which point the pilot was still pulled in and should have pushed out, then the sail blew down and the glider tumbled twice and then the sail falied and on the 3rd tumble the opposite side leading edge failed. The glider hit on a wing. (The glider tipped to a side after the sail failed.) The impact was greatly absorbed by the glider. The injuries were a broken femer (a thigh bone) and concussion. The pilot threw his parachute only to watch it hit the ground before he did.

After talking to you the apparent things we did wrong were: (1) No weak link, (2) no elastic built into the line (3) no scale, (4) pop start. He used a 3-ring release system opposed to your system. This was my choice due to years of absolutely fantastic results in sky diving. If you want a set, let me know and I'll send them out.

We still (it hasn't been easy) have an open mind towards towing at Wills Wing and are ordering a better winch that won't lock up. I believe towing can at least double the size of hang gliding and add at least 50 miles to XC flights and is well worth the development. I and just feel it is ridiculous to make the same mistakes that others have made through lack of communication.

Rich Pfeiffer
Wills Wings
Santa Ana, CA
*
1983/03-05

COMMENTS

Before writing his letter, Rich called me to tell me about this accident. During our conversation, he discussed some of the factors which he felt may have contributed to the accident. He felt that to a large extent, the accident was a result of their own fatigue, lack of knowledge, and inexperience on the skyting system. Specifically, he felt that (1) the group was growing tired by the end of the day when the accident occurred, (2) they had become somewhat complacent about the potential dangers of towing as their initial fears subsided, (3) they were not really knowledgeable about skyting systems and skyting theory, and (4) no one there had had adequate skyting experience to be supervising their training sessions.

In my opinion, the most glaring mistake made by the group was their failure to use a properly designed weak link. When the perlon bridle broke at 500+ pounds or so, a whipstall with its corresponding loss of control was inevitable. Had they been using a weak link that broke at 200 pounds, the pilot could have easily flown out of trouble. As it was, when the auto-release line gave way, the full thrust of the towline was transferred to the pilot's body, which was below the center of mass of the pilot-glider system. This caused the glider's nose to rotate up and very quickly the tow forces exceeded the limits of the weakest link in the system (which in this case was the bridle). The whole incident occurred at approximately 100 to 150 ft above the ground. As a result there was insufficient time for the pilot to deploy the parachute and recover.

From Rich's description, they also made a mistake by using a payout winch (or reel) which failed to deliver constant tension. If the winch had been doing it's job properly, the forces never would have been built up enough to break the towline even if the top latch had given way). This demonstrated the extreme importance of having a winch or reel system which is capable of maintaining true constant tension. It obviously is not cost effective to skimp on buying your winch.

A third mistake they made was their failure to incorporate provisions for making a gradual transition to and from towing. Apparently their winch was not capable of gradually increasing the tension and they were not using an elastic towline. As a result, the tension increased so rapidly when the latch gave way, that it was impossible for either pilot or crew to respond properly.

This lack of towline stretch also resulted in a slack towline when they tried to tow with a low tension setting. To eliminate this slack towline problem, they set the winch to a higher tension value, and increased the velocity of the automobile immediately after take-off. This produced another problem which Rich mentioned. The high tension combined with the strong upward push on the control bar by the bridle line underneath it, caused the pilots to have pitch control problems-namely, they could not prevent themselves from climbing too fast. From Rich's description, I suspect they were towing with about 200+ pounds instead of 75 or 100 pounds. I guess this large a tension can be handled all right as long as the tow force remains truly constant, but it certainly does not leave very much room for error.

Another factor that apparently contributed to the accident was the use of a pop-start instead of a gradual start. Although an experienced tow pilot should be able to handle a pop-start, it is considered poor skyting practice, as it violates the gradual advancement provision. It is particularly inappropriate to use a pop start on a pilot's first tow flight, as apparently occurred in this situation. Rich also mentioned that there was a significant wind gradient at the time, so it's possible that this contributed to the problems in that as the pilot climbed to higher altitude, the tow force increased dramatically. Here again a true tension limiting device or tension measuring device would have detected the problem and possibly eliminated this mistake.

The really sad part of this accident is that it could have been avoided. I'm convinced that the accident never would have happened if the pilots involved had throughly read and understood the back issues of Skyting. As it was, the pilots had heard about the increased safety that skyting affords and had learned enough to feel that they could try it on their own. But they had not throughly acquainted themselves with the dangers or with the skyting theory that explains why skyting is safe. These were not inexperienced pilots, but some of the best pilots in the nation. The accident illustrates the extreme importance of pilots that attempt to skyte learn what other problems other pilots have had and understand the theory behind the skyting system. In your enthusiasm of spreading the word about skyting, please encourage your friends to read the material that's available before attempting to use the skyting system themselves.

Donnell
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1983/03-06

HOW TO BREAK THE OTHER ARM

by Donnell Hewett

You will recall from Skyting No.1 that I broke my left arm in a skyting related accident. Well, you're not going to believe this, but I've done gone and done it again, except this time it's my right arm. Yes, the champion of safe towing techniques, yours truly, the one who says skyting is the safest way to tow hang gliders, has just broken his other arm in a skyting related accident.

In fact I've got a new name, it's "Crash Hewett". My friends ask me, "Donnell, what is it going to convience you to stop hang gliding?" I reply, "Enough already, I'm convienced. I'm going to stop hang gliding at least for the next six months."

DESCRIPTION

The first question someone ask when they see my arm in a cast is "How did it happen?" Well my family (my wife Helen and my two girls Tahnya and Tammi) and one crew member (Mike Greene) went out to Padre Island to do some flying. The winds were strong but smooth blowing at about 15-mph and every once in a while, getting up to around 20-mph.

We set up the glider and I did some ground handling on the 500-ft towline attached to the van. My ground handling ability had improved significantly since I first tried to ground the Gemini, (see Skyting No. 7). Apparently I was finally learning to control this glider and to get it to do what I wanted it to do. During this ground handling exercise, it soon became obvious there was not enough wind to kite. In order to get the glider airborne, we were going to have to tow it.

My wife and girls went over to the van to get it ready to tow and, while Mike and I were waiting for the conditions to get just right, the wind picked up. If fact, it became strong enough to blow Mike's cap off his head. I told him to go ahead and get his cap and that I would hold the glider until he got back. But as soon as he left, I noticed that the wind speed seemed to pick up even more and I thought that this surely was enough wind to kite in, so I decided that I would go ahead and take-off.

Instead of holding the nose down as I had promised, I picked up the glider, lifted up on the control bar and let the glider start to climb. It climbed about 3 ft and then apparently stalled. The left wing dropped down and hit the sand and of course, at that point, I no longer had any control over the situation. The wind continued to lift the high wing until I was looking straight down the other wing toward the ground 25 ft below. I then came crashing down on top of the glider as it continued to roll upside down.

Needless to say, I hit pretty hard, but the glider took much of the impact and the sand on the beach was at least somewhat forgiving. Nevertheless, I broke my arm just below the shoulder. Fortunately, no other damage was done except for the glider. There I broke one leading edge, both down tubes, the forward keel, and several battens.

ANALYSIS

After an accident like this, it is very important to review the conditions under which it occurred in order to try to find out what mistakes were made and what can be done to prevent it from occurring in the future. As with most serious accidents there are several lessons than can be learned from this unfortunate experience.

My major mistake was in attempting to take off in winds that were below the stall speed of my glider. If I had simply followed the plan we had already agreed upon, waited until Mike got back, given the vehicle the go signal, and proceeded with a normal skyting tow flight then I am convienced that the accident would never have happened. I doubt that the vehicle would have ever had to travel more than 5-mph, and once I had traveled up the wind gradient, it probably could have stopped competely. I could have then done all the kiting that I wanted to, but at a safe altitude. Instead, I let my impatience get the best of my and now I am paying the price.

A second lesson to be learned is that a noseman is definately needed in a kiting situation. This incident proves that any time the winds are almost adequate to lift the glider and pilot into the air, they are more than adequate to ground loop the glider. Therefore, someone should always be there to assist the pilot in controlling the glider in case something does get out of hand. So my second mistake was not 'waiting' for Mike to get back before attempting to take off. Even if the air had been adequate for kiting, I should have waited until he got back.

A third lesson to be learned from this incident, is that the pilot should not "change horses in the middle of the stream." In other words, he should not change his plans without informing everyone in the ground crew. My attempt to take-off without anyone in the ground crew knowing what I was doing made it impossible for them to correct for any of my mistakes. For example, if my wife had known what I was doing, it is conceivable that she could have accelerated the vehicle and pulled me out of danger before the situation got too bad. Similarly if Mike had known what I was doing, he would probably have let his hat go and come back to assist me. I certainly made a mistake in changing my mind on the spur of the moment, and failing to inform my ground crew what my plans were.

A fourth lesson to be learned from this incident is that I am not immuned to having broken bones. In fact, I am beginning to suspect that my bones may be more brittle than those of an average person. At least I'm going to assume this is true in all of my future flying. To be honest, both times that I broke my arm, I was surprised that the bones broke. In the first case two years ago, as I went through the control bar, I knew of the danger of breaking an arm, so I relaxed my muscles and permitted my body to swing through the control bar as freely as possible. I was therefore, somewhat surprised when the bone did break. This time I did not swing through the control bar, but let the glider take as much of the impact as I could. Certainly I hit hard, but I did not even have my breath knocked out of me, nor did I go unconscious, nor did I hear any bones break. But when I tried to get up, there I was with a broken arm. Again I was surprised.

A fifth lesson to be learned from this accident is: if you're not going to fly right, don't fly at all. The first time, I broke my arm at the end of a fantastic flight, but this time, I broke it on the very first launch attempt. I don't believe any flight, no matter how fantastic, is worth a broken arm. So breaking an arm without even getting a single flight is certainly not worth the effort.

NATURAL REGULATION

Last month I wrote an article about Natural Regulation, and about the safety aspects thereof. If we look at this accident from the point of view of that article, I think you can see that I broke all 5 of natures laws: (1) I was clearly out of control, (2) I stalled on takeoff, (3) I crashed instead of landing, (4) I failed to avoid having my wing tip hit the ground, and (5) obviously I exceeded both the limits of my equipment and myself.

So all in all, I believe nature was pretty forgiving by letting me get by with just a broken arm and a damaged aircraft. Of course, I am going to have plenty of time to get the hang glider repaired, my arm will be in a cast for two months, and then I expect about six months rehabilitation before my arm gets back to full capacity.

But the real embarrassing part of this accident is the fact that it demonstrates so clearly my own poor judgment when it comes to flying. I have spent a tremendous amount of effort trying to figure out the conditions under which safe towing can take place. And I honestly believe that I have discovered these conditions. The fact that I seem to be unable to follow my own advice is very discouraging.

Everyone likes to believe that they are smart enough to make wise decisions which effect their own lives. Of course mistakes are understandable if the person does not know any better, but in this case, I knew better. In fact for several years I have been preaching against the very same mistakes that I made. Perhaps, just perhaps, one of the days I am going to learn to follow my own advise. In the meantime, I suggest that you do as I say and not as I do.
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FROM WATER TOWING TO ICE TOWING TO ROPE SOARING
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1983/03-07

Dear Donnell,

Here is a letter to let you know how your Skyting system is working for four fliers in northern Minnesota. To date I have sixty six flights. My wife Terry has twenty three. Our friend Gene Stone, who had no towing experience prior to Skyting, has sixty five. Our friend Don Ray has eight.

From your Skyting #1 I put together all the necessary stuff with the exception of the tensioning device and weak link. All of our one hundred and sixty two flights, except the first four water tows, have been done with a 196 lbs (plus or minus) 15 lbs weak link of #18 twisted nylon with 170 lbs breaking strength. With some testing and experimentation I found three different knots, when tied so as to from a loop, that will give breaking strengths of 162 +- 8 lbs, 196 +- 15 lbs, (which we are currently using) and 220 +- 3 lbs.

Of the first four flights, without the weak link, three were deep water starts. The other was a running beach start. My wife, an experienced "pin-person" of over 2000 conventional tow flights, was trusted to keep the climb rate and altitude low and slow for the testing of the new system. I have always said that tow flight is four times harder to do than free flight, but your Skyting system makes tow flight as easy as free flight. All other flights have been done on frozen lakes behind a small snow-mobile. We started with 150' of tow rope then slowly worked our way up to 810' to date.

After finishing Skyting #9 I get the idea that I'm not the only one having a problem with the weak link in a deep water start situation. The trees grow right up to the lakes around here leaving little or no beaches to do running starts. One thing I was going to try next spring to allow a deep water and still have the protection of a weak link is this: Take the 3/8" poly rope off our winch (reel actually) and put on the 1/8" white nylon cord that we tow with. For the leader, between the 1/8" line and the skyting bridle, we will put 250' of 3/8" polypropylene rope. To start out we will have all but six turns of the leader played off of the winch between the boat and the kite. We will then hold the break until the kite leaves the water. Then we will release the break and the reel will be it's pretention mode. In six turns of the winch all of the remaining 3/8" leader with weak link attached will be pulled off the drum and give the pilot the protection of the weak link for his/her ascent.

One problem my wife had was the top (keel) rope draped around her neck. She untangled herself and decided to release with more tension on the tow line and has had no more trouble. That, sofar, is the only thing causing me any concern- that the top release could become tangled on the flying wires, pilot or base tube under various possible circumstances. I'm going to keep an eye on Skyting news to see when someone resolves this potential problem to my satisfaction.

We have had no problem with stalls when a weak link breaks and are thinking of trying our 220 lbs weak link. We get up to 700'/min climb rate on our 196 lb weak link before it breaks. We usually hold the climb down to 500'/min. Our 220 lb weak link is #18 nylon string with both ends tied to form a loop my means of a double fishermans knot. (see figure). I haven't found a weak link between 196 and 220 lb. Do you think 220 lbs is too big of a jump?

We had to eliminate the plastic sleeves on the releases. They broke when dropped because of the cold.

For some reason he parachute cord tow line didn't stand up to being dragged through the snow, but the 1/8" white colored nylon cord is holding very well.

We haven't thought of a way to incorporate the tensioning device in our snowmobile operation yet. On no wind days we have a hard time keeping the climb rate up to 400'/min. On windy days the snow machine track gets light and slips when pressure builds close to 200 lbs, so usually the driver is trying to go as fast as traction will allow which is just short of breaking the weak link. Some days, because of temperature, moisture content of the snow or had packed snow the driver has to watch for a slow signal. Any ideas for a tensioning device with this type of operation?

By the way don't try touching the basetube with your wet tongue or lips in below freezing temperatures flights if you intend to flare at the L.Z.

We plan to keep in touch with any new information we might stumble over.

Oh yes! I just about forgot to say that twice I have rope soared at the end of a 810' rope with the snow machine stopping and the driver holding the brake to keep the snow machine from backing up. The longest was for 25 min. Then Don started walking back and pulling the rope down as he went. "It's hard to soar with the eagles when you're working with a turkey." When I got to about 400' the wind wasn't strong enough for me to maintain my altitude. I signaled "faster" and Don putting the rope over his shoulder slowly trudged back to the snow machine allowing me to maintain an alt. of 400'. Once again at the machine he couldn't manage to start the machine and hold the tow rope so I had to come down.

Thanks for Skyting. Enclosed is $2.00 for Skyting #10 & #11.

Bill & Terry Cummings
Hoyt Lakes, MN
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1983/03-08

Dear Bill & Terry,

Thank you for writing. Here is the Skyting No.10 that you requested. Skyting No.11 will be sent as soon as it is completed.

Say, I like your idea of wrapping the leader around the winch a few times so that after a deep water start it can be fed out to give the protection of a weak link. Let me know how things work out in this regard.

Several pilots have also been concerned about the auto-release line tangling on the pilot's neck. I think you'll find in the back issues of Skyting that some of them reverse the auto-release to put the release on the body instead of on the keel. Then by releasing the keel latch manually, the rest of it goes automatically. I personally simply tow to the side and take care that the lines do not get in my way.

Now concerning the weak link, the general rule that we follow is that it ought to break at one "g" of force. This means a 160 pound pilot flying a 60 pound glider ought to have a weak link that breaks at 220 pounds. Therefore, I see nothing wrong with your increasing your weak link break point up to 220 pounds. In fact, the difference in 196 pounds and 220 pounds is only about 10%, so I doubt that you'll notice much difference in actual performance.

I'm sorry to hear that the plastic sleeve that you were using broke in the cold weather and to be honest, I'm curious as to what you are using now for a sleeve. I was also surprised to find the parachute shroud line did not stand up as it was drug through the snow. It stands up quite well as we drag it across the ground. Nevertheless, I'm glad to hear that you solved your problem and that the 1/8 inch nylon cord does well.

Now concerning the tension measuring device, I'm afraid that very little work has been done in this area. As you know, we use a spring and run a rope to the driver's hand so he can feel the tension in the spring. You could use a spring on your snow mobile and read it directly. In my opinion, the ideal tension measuring device, would be some kind of electronic device which gives a readout which is either audible or visible by the driver.

Of course, you realize that you can use a vehicle speedometer or an air speed indicator on the vehicle as crude devices to tell you how fast you ought to be driving.

You are first person outside the are to report having done some rope soaring. The 25 minute flight that you had is a rope soaring record as far as I know. As you gain more experience in this area, please let me know how things go.

By the say, we don't have much trouble here when we touch our tongues to the control bar in below freezing weather. We haven't even had below freezing weather here this year.

Good skyting.

Donnell
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OBSERVATIONS FROM NORTHERN CALIFORNIA
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1983/03-09

Dear Donnell,

I was intrigued by a sailplane launch which I read about recently. Among several airfield lauch methods was one using a fixed pulley at upwind end of the field. The tow vehicle starts at the pulley and drives toward the launch point with the line. As the vehicle reaches the launch point the plane releases. The vehicle unhooks and drives back toward the pulley and turns around. The line is already stretched out so he reattaches at the end by the pulley; ready now to tow the next sailplane. With this method, many tows could be made and the line does not have to be reeled up. The line used, by the way, is steel. Also, the driver can observe.

A tow launch using the center of mass principle has been used occasionally in California. Coastal pilots towed by holding a rubber bit between their teeth. The line was elastic attached to a motorcycle. I think Condo Soaring in Flordia uses this type bridle with people providing the power.

The folks at Manta, using a Foxbat (Trike/Fledge III), tow their Fledgling by attaching just one line to the noseplate of the Fledge. The Fledge is equipped with wheels and rolling starts are used.

Hang glider pilots have long known of a dangerous act committed by beginners and advanced flyers. It is the failure to hook in. This phenomena could happen to anyone at anytime. Please make the hang check a requirement of all pilots.

An interesting sailplane soaring technique is to create thermals artificially. Black plastic is suspended several feet above the ground. After the air beneath is heated sufficiently, the thermal is released by dropping long narrow panels of the plastic. Should the glider be in the path of the rising bubble; wham instant lift. Skyting pilots could take advantage of this thermal better than mountain pilots due to the nature of our flatland sites.

I made some copies of your material, but will send you some money when I sell and/or rent them to our club members. I am grateful for your contributions to the hang gliding community and would never rip you off.

Tim Summerfield
Carmichael, CA
*
1983/03-10

Dear Tim,

Thank you for sending me your Dear Donnell letters. They contain some very interesting ideas. Here are a few comments about them.

The idea of using a fixed pulley and flying toward the vehicle is intriguing and does show promise to reduce the turn around time for skyting flights. I can understand why a steel line is being used (besides the fact that a conventional glider is being towed) because the line will be dragging at full tension along the ground during the tow process. I do not know how long an elastic towline (which is a skyting requirement if no winch is being used) would hold up under these conditions.

I had thought of using a fixed pulley similar to what you described except that my idea was to eliminate cross-wind take-offs by having the vehicle travel along a road and having the glider pulled across a field into the wind. This would permit roads to be used which had telephone poles, trees and other obstructions along the side, as well as eliminate the cross-wind takeoff problem, I have never actually got around to trying the system. I'm sure someday someone will. I would be interested in hearing the results.

When the pilot holds the towline between his teeth, (OUCH!) it is not a true center of mass bridle system- it is probably more of a body towing system (but of course as Skyting No.1 points out this is closer to a center of mass towing system then is a towing system that tows from the glider itself). However, it does solve several of the problems associated with some of the other skyting systems. It certainly has a reliable release system (as well as a built in weak link) and there is probably very little danger of the towline tangling with the glider. But personally I don't think I would want to tow up to catch a thermal using such a system.

When towing a Foxbat as with towing any trike/hang glider combination, it makes sense to attach the towline to the trike noseplate. Almost all of the mass of the system is in the trike-pilot portion, therefore, the tow force would automatically pass reasonably close to the center of mass of the system. This would be true at all but the highest tow angles. There the downward force on the front of the trike might produce some torque problems. But I doubt if the people at Manta have encountered this problem because by the time the pilot is towing to that height, he has probably got his engine running and is no longer using the towing system.

I agree that failure to hook in is a very dangerous act and pilots should continually be reminded of this danger. The hang check therefore, should always be performed immediately before the take-off attempt. The fact that skyting (take-offs on level ground) is more forgiving of this act than conventional hang gliding (take-offs from the side of a mountain) could make skyting pilots careless in this regard. But if the develop a habit of taking off without a hang check, it's going to catch up with them eventually when they do start flying off the side of a mountain.

I have often thought of creating artificial thermals, but have never heard of anyone actually doing so. If the technique is practical it certainly sounds intriguing. By properly timing a skyting take-off with the release of an artificial thermal, a good pilot could almost be guaranteed a high altitude launch in the flatlands.

Thank you for helping to distribute the information contained in the Skyting Newsletters. I think it is important to get this information in the hands of every pilot who is contemplating towing. For each copy that you make, please send me $1 minus the cost you incurred in making the copy, minus 20 cents postage that it would cost me to send the copy out. (Using this formula, I doubt that you will be sending me much money, but every little bit helps as far as skyting development is concerned). If you rent copies to your club members, then send me whatever you think is fair, or else keep all the proceeds for your club. (I am sure that any rental fee you charge just barely keeps your library going.)

Donnell
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[Tad Eareckson]

1983/04
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SKYTING NO.12
APRIL 1983
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1983/04-01

1982 TOWING ACCIDENTS

According to Doug Hildreth's annual USHGA Accident Report: "There were 3 towing accidents. A beginner was killed when he presumably locked out while being towed by a car in Texas. A people tow locked out, and the release failed - broken leg. A boat towed glider locked out, the boat released, the glider recovered, the G forces caused a homemade swing seat to fail, with serious injuries."

The fatality occurred on February 22, 1982, when Ted Walkowiak, age 30 with little or no experience, was towing near Frisco, Tx. The glider was being pulled by a car, "rose to 300 feet, was buffeted by a crosswind and plunged to the ground."

None of these accidents were skyting related. All three were apparently the result of lockouts.

In addition to the above accidents, I recently heard of another serious towing accident that happened last summer. It was another lockout while land towing with a conventional system. This report convinces me that not all towing accidents are being reported to USHGA. Since this information is important to towing safety, let's all help support this effort by reporting all accidents we hear about.

No skyting accidents were reported to me for the 1982 year. I hope this means that none occurred. But it could also mean that those which did occur were not reported. Again, please report the accidents which you know about. This is the only way dangerous practices can be identified.

You will notice from Skyting No. 11 that two skyting accidents have already occurred this year.

(By the way, Rich Pheiffer ((Pfeiffer)) was not the pilot who broke his leg in the California accident. Rich simply witnessed the accident and reported it. I do not know the name of the injured pilot. I am sorry if the article left you with the wrong impression.)

Please do your part to see that this unfortunate trend does not continue. Please skyte safely.
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1983/04-02

A THEORETICAL SOLUTION TO THE ADVERSE YAW PROBLEM

by Donnell Hewett

Several pilots have observed that when a high performance glider is towed with the skyting system, the glider frequently tends to yaw in a direction opposite to that in which it is being towed. This adverse yaw phenomena can easily result in the pilot's over control of the glider as he attempts to correct for the yaw, first in one direction and then in the other. Apparently certain gliders are more susceptible to this adverse yaw problem than others, and there seems to be general agreement that this adverse yaw tendency can be reduced by moving the tow point back along the keel to the suspension point rather than keeping it forward as illustrated in Skyting No. 1. Although the adverse yaw problem is not as dangerous or as pronounced as the lockout used to be, it is still responsible for some rather frightening experiences. And in my opinion, it is the primary control problem in skyting.

When I first heard about the adverse yaw problem, I was not convinced that the problem was real. According to skyting theory, the glider ought to behave on tow the same as it does in free flight and I, personally, had never encountered any adverse yaw tendency while towing my standard Rogallo. (At that time I had not towed a high performance glider.) Furthermore, the problem seemed to be associated primarily with pilots who were experienced with conventional towing and who were flying high performance gliders. Since they were used to the strong control input and sluggish response of conventional towing systems, it was understandable why they overcontrolled their gliders while testing out the new, faster responding skyting system. And as they became more experienced on the skyting system, they learned to handle the adverse yaw problem sufficiently to proclaim that skyting control was vastly superior to that of conventional towing. But even so, some of the pilots continued to insist that the adverse yaw phenomena was real and that certain gliders were more susceptible to it than others.

When I finally bought a modern glider and had an opportunity to fly one for myself (see Skyting No. 7), I personally encountered the adverse yaw problem for the first time. Again I could not be certain that the phenomenon was due to the skyting tow system or due to the fact that I was inexperienced on the new Gemini that I was flying. I know that most modern gliders had a tendency to adverse yaw when free flying, so I still could not be certain that the skyting adverse yaw problem was any more pronounced than the free flight adverse yaw phenomenon.

But as I gained more experience on the Gemini-both on and off of tow-and as I listened to the comments of other pilots, it became obvious that the skyting adverse yaw was indeed more pronounced than the free flight adverse yaw. This bothered me because theoretically it ought not to be so. It also bothered me because the Gemini simply did not handle as well on tow as in free flight - and, when I tow a hang glider, I want it to handle as well on tow as it does in free flight.

I kept hoping that someone would come up with an explanation for the adverse yaw phenomenon and, therefore, a solution to the problem. But since I was beginning the encounter the problem myself, I felt that I would have to stop waiting on others and start analyzing the problem in more detail, myself.

ANALYSIS

I am not a professional hang glider designer and really do not fully understand the significance of some of the subtle design characteristics of modern gliders. Therefore, this analysis may not be totally accurate. But I asked myself, "What happens to a modern glider when the glider first turns just a little bit sideways to the towline?" Suppose, for example, a gust of wind hits the glider or for some other reason the glider's nose yaws slightly to the right of the direction in which it is being towed. Then what happens?

Well, if the glider's nose yaws to the right, the tow line attached to it's keel is going to pull the keel to the left. This will cause the keel pocket to shift to the left, tightening the sail on the right wing of the glider and loosening the sail on the left wing. This in turn will produce more drag on the right wing, slowing it down, and cause the left wing to speed up. Therefore the glider will yaw farther to the right. As the glider's nose points farther to the right, the keel pocket is forced farther to the left and the whole process is amplified until the glider is in a pronounced right yaw.

Well, this explains the adverse yaw phenomenon, but what about the roll response of the glider? If the right wing is tightened, then it should experience more lift than normal. (And the left wing which is loosened should experience more lift than normal.) Hence, the right yaw should be accompained by a left roll (which tends to eventually bring the glider back into the correct alignment).

But this left roll does not seem to take place in practice. It has been my experience (admittedly quite limited) that the glider also tends to roll to the right! But why?

Well, there are two reasons. In first place, you will recall that as the glider yaws to the right, the right wing slows down and the left wing speeds up. The slower moving right wing looses lift while the faster moving left wing gains lift, so the glider tends to roll to the right.

The second reason for a right roll tendency is the fact that as the glider yaws to the right it is being towed to the left. This causes the air to "hit" the left wing "harder" than it is hitting the right wing. This in turn produces more lift on the left wing and less lift on the right wing so that again the glider rolls to the right.

The roll response during the yaw, therefore, is ambiguous. The tension in the sails makes the glider want to roll to the left but the speeding and slowing of the wings and the relative wind make the glider want to roll to the right. Which of these two rolling tendencies dominates depends upon such factors as the angle of attack, the amount of yaw, and the direction of the towline. Again based upon limited experience, I get the feeling that the adverse roll dominates at first, but then a point is reached where the glider tends to roll back toward the towline. Since the two rolling tendencies to some extent cancel one another out, it is the yawing phenomena which is most apparent to the pilot. (Hence the terminology: "adverse yaw phenomena".)

But this conflict between the two rolling tendencies explains another phenomena commonly associated with the adverse yaw - namely the tendence for pilots to over control. Specifically, at the beginning of the adverse yaw the adverse roll dominates and the glider rolls away from the towline. The pilot shifts his weight back into alignment. Eventually the rolling tendence reverses itself and the glider rolls back toward the towline. When this reversal is combined with the pilot's weight shift, the glider over reacts and starts the adverse yaw in the opposite direction. The whole process repeats itself as the pilot goes into an over control oscillation.

BACK TO BASICS

The preceeding theory seems to explain most of the phenomena associated with the adverse yaw problem. However the foundation of this theory is somewhat shakey and, although I feel that the theory is valid, I cannot be certain of this fact. Furthermore, even though the theory does explain the adverse yaw phenomena, it does not point a way to its solution. So let's approach the problem from a different point of view. After all, when detailed analysis is not convencing, then it is time to go back to basics.

According to basic skyting theory, (see Skyting No. 1), if the towing forces are distributed between the pilot and the glider the same way that gravity distributes its forces, then the performance of the glider has to be the same on tow as it is in free flight. But we have already admitted that the glider does not perform on tow the same as it does in free flight. What then is wrong with skyting theory? Nothing! It is not the theory that is wrong, but our application of the theory!

Specifically, we have assumed that attaching the towline to the center of the keel is the same as attaching it to the center of mass of the glider. But this is not ture. With the modern cross-bar gliders, the bulk of the mass is able to move relative to the keel. Think about it. How much of the mass of the glider is contained in the keel? Very little. By far, the majority of the mass of the glider is contained in the leading edges, the cross-bar, and the sail, itself. At least 80% and probably 90% of the mass of the glider is contained in its wings and wing structure. Furthermore, the wings, (even flex wings) of the glider act as a rigid body, where as the keel is designed to move with respect to these wings. (If you don't believe this, watch a pilot ground handle a modern glider. There you will see that it is the control bar and the keel that flop aroung - not the wings or the cross-bar.)

Since it is the wings of the glider that act like the rigid body and the wings that contain most of the mass of the glider, then obviously to meet the skyting criteria, one should attach the towline to the center of mass of the wings rather than the keel. In practice, this means that the bridle should be attached to the cross-bar instead of the keel. That's right, those gliders which have a pronounced adverse yaw tendency should have their top bridle lines effectively attached to the center of the cross-bar in such a manner that the keel is free to move from side to side unhampered.

PRACTICAL CONSIDERATIONS

Of course, there are certain problems that arise when you try to attach the upper bridle line to the cross-bar. Namely, where do you attach it? You obviously cannot attach it to the center of the cross-bar, for then the bridle line would have to pass through the keel. Nor can you attach it to one side of the cross-bar or the other side because this would produce a sideways torque on the glider. Obviously some type of Y-shaped connector is going to have to be used with the top of the Y connected to each side of the cross-bar so that the keel runs between the two lines and is free to move from side to side. The upper bridle line, then, constitutes the bottom of the Y.

Another problem arises when double surface gliders are employed. Namely, in order to attach the bridle line to an enclosed cross-bar, a hole will have to be made in the glider's lower surface. In fact, to connect the Y-system described previously, two holes will have to be made! And the whole configuration must be designed so that the glider can be folded up after each flight. Since the owners of most high-performance, double-surface gliders are not likely to relish the idea of making holes in the wings of their gliders, it may be a while before we see cross-bar towing with double-surfaced gliders. Yet double-surfaced gliders are among the ones which have the greatest tendency toward the adverse yaw characteristics.

But the greatest problem about towing from the cross-bar is the fact that the cross-bar is not designed to withstand any significant downward pull. Although the forward pull of the cross-bar during the take-off should present no problem for most gliders, as a glider climbs to higher tow angles, the downward pull on the cross-bar could conceivably pull it down until it begins to rub against the keel. Depending upon the particular glider design, the result could be bent or broken components, and/or a failure of the cross-bar to "float" properly. And if something bends, breaks, or jams, then the glider could be forced completely out of control!

Of course, if one is using a weak link which limits the tow force to one "g", then the maximum downward force on the cross-bar will be equal to about the weight of the glider. Since most gliders can be lifted by the cross-bar without resulting in any damage, then it seems reasonable that they could also withstand an equivalent downward force on their cross-bar without any trouble. If this is true, then it should be possible to pull a hang glider from its cross-bar without any jamming of the floating cross-bar action.

Of course, if the downward pull on the cross-bar does not produce any damage or reduced control, the pilot could devise a system for supporting the cross-bar during towing operation. For example, he could attach a support line from the cross-bar up to some point on the king post. Or he could devise a spacer between the cross-bar and the keel which permits the cross-bar and the keel to move sideways but which prevents the cross-bar from being pulled down into the keel. There are several ways to accomplish this, but at this time I do not know which of these many possibilities is the best approach.

It would appear, then, that none of the problems associated with cross-bar towing are insurmountable. But the question remains, "is the increase in glider performance worth the extra effort?"

The answer to this question, of course, depends upon the particular glider being used and the type of towing that is being performed. Certain gliders, as stated before, are more susceptible to the adverse yaw problem than others. There is obviously no need to cross-bar tow a glider which already tows well from its keel. But the pilots of those gliders which do exhibit a strong adverse yaw tendency should seriously consider switching to the cross-bar towing technique.

However, even gliders with a strong adverse yaw tendency can be controlled by an experienced pilot. (Yes, the control is more difficult, but it can be accomplished.) Therefore, if the tow flight is short - i.e. if the glider is being towed solely for the purpose of reaching an altitude high enough for free flight - then again it may not be worthwhile to switch the tow point from the keel to the cross-bar. In other words, if the pilot's main interest is free flight and he is using towing only for the purpose of launching his free flight, then he may prefer to keep towing from the keel in spite of the adverse yaw tendency of his glider.

However, if a pilot is interested in making prolonged tow flights, in rope soaring, or in retaining the maximum control of his glider while on tow, then he will want to switch the attachment point from his keel to his cross-bar. This is particularly true if his glider has a strong adverse yaw tendency.

Personally I do not like the feel of the adverse yaw phenomena and want my glider to have as much control as is possible. So if the above theory is valid, I plan to tow from the cross-bar.

EXPERIMENTAL RESULT

Unfortunately the above adverse yaw theory has not been tested experimentally. I was planning to test it on the day that I broke my arm. (See Skyting No.11.) In fact, I was towing from the cross-bar when I ground-looped my glider. (But I do not believe that this had anything to do with the accident.)

Before the accident occurred, I spent several minutes ground handling my glider in conditions which were almost kitable. These conditions were very similar to those described in Skyting No. 7 where I ground handled the Gemini for the first time. You will recall in that article that I said that the Gemini was much more difficult to handle than the standard Rogallo that I was used to flying. But this time, with the bridle line attached to the cross-bar, the Gemini responded in a more natural manner reminiscent of my old standard. In other words, the Gemini was much easier to ground handle this time than it was the first time.

How much of this increased control was the result of my moving the attachment point and how much was due to my increased familiarity with the flying characteristics of the Gemini as I gained experience, I do not know. But I suspect that it was some of both.

I really feel bad about presenting the theoretical solution to a problem without experimental confirmation of the theory. But since it is impossible for me to test the theory myself, the only alternative is to not publish the theory at all. This, I felt, would be a disservice to the skyting community. If the theory is true, then it could help a lot of pilots gain better control of their gliders while on tow. If the theory is false, then someone could get hurt while testing it. But whether ture or false, the theory contains information which should be made available to those pilots who are interested. What they do with this information is their choice and their responsibility.

From what I read, most pilots are already reasonably satisfied with the control characteristics of their glider while skyting from their keel. Such pilots should obviously continue towing the way they are, and wait until this adverse yaw theory is experimentally confirmed before even considering the possibility of changing their tow point.

But those pilots like me, who are not satisfied with the control afforded by keel towing, may want to test this theory to see if it is true or false. Of course, they should proceed with extreme caution while making these tests. (Remember, I broke my arm while testing this theory.)

By the way, if you decide to test this theory yourself, please let me know the result as soon as possible. There is certainly no need for others to repeat these tests if the result is positive, then other pilots need to know that the adverse yaw problem has theoretically been solved.
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1983/04-03

UNOFFICIAL RECORDS

Here we are into the month of April and on one has reported any significent skyting flights already. To be honest, I am a little surprised. By now I would have expected someone (in the southern states) to have made some kind of cross country flight. If not that, then at least a local soaring flight (altitude gain after releasing). If not that, then at least a local soaring flight (altitude gain after releasing). If not that, then at least a towed flight to 1000 ft or more. But none of these have been reported.

Come on, youse guys, if you've done something (or seen someone else do somethin) which has never been done on or from a skyting system, assume you are the first (you probably are) and report it. By doing this you will be helping us establish a history of skyting progress and gain a better understanding of where skyting stands at its current stage of development.
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1983/04-04

Dear Donnell:

Yahoo; pull that rope, give us lift, Texas rises again.

Me and this old Seagull III are awaiting a safe way to tow above these here low hills and ponds of mid-Michigan.

I agree with your views on current "proven" towing systems and feel that your ideas and system are far safer.

Will & Sara Wyckoff
Greenville, Mich.
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STATIONARY TOW VEHICLE
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1983/04-05

Dear Donnell:

I would like to relate our first experience, here in Nova Soctia, with your Skyting system. The first day we had it out the winds were 15 to 20 mph, so we static lined and managed to get off the ground but that was about it. The harness felt comfortable so we were more confident about winching the second day. Thats right, winching.

At this point I would like to pass on a development that should go hand in hand with the harness ((bridle)) to make hang gliding over flat land as practical as flying anywhere.

First lets qualify a winch. A device capable of reeling in line or cable in order to move an object attached to the opposite end if the same line or cable. A winch for hang gliding must do a lot more than just reel in line. It must also be able to pay out line, have a variable speed both reeling in line as well as paying out line, sufficient power to overcome the drag of the kite and pilot, smooth transition when the winch is engaged, and it must be practical.

I have a winch that meets the above criteria plus a whole lot more. I wish I could say, send $9.95 to the above address and I will send you a winch, but I can't. I can't because almost everyone already owns one.

It comes in the guise of an automobile. As an auto mechanic I was quick to realize the potential of using an auto as a winch. Here's how you can turn your ride to the flying site into your ride to the clouds. (caution: positrack vehicles will not work)

Obtain a rim at a junk yard to fit your vehicle. Jack up your left rear wheel or left front wheel for front wheel drive cars. Remove the wheel, be sure to block the outer three wheels so the car/truck is stable. Install the rim and secure with the nuts. Mount a guide to the car in a position that will allow the line to clear the body and reel directly on the center of the rim. Insert your tow line through the guide and attach it to the rim. With someone holding tension on the line, start the engine and apply the brake. Put the car in gear, as the brake is released the rim will reel in the line.

If you have any questions or comments please refer to the above address.

Here's to flat land flying,

Timothy P. Churchill
Armdale, Nova Scota, Canada
+
STV (stationary tow vehicle
wheel blocks
Jack
rust
eye bolt
Tow line

Tim Churchill
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1983/04-06

Dear Tim,

I can't believe you made your first skyting flights in 15 to 20 mph winds. Don't you think this is putting a little too much faith in a tow system which is still very much in the experimental stage of development? I certainly hope you are meeting all eight of skyting's criteria (See Skyting No. 3) and not just using a skyting bridle on a conventional towing system.

By the way, I really like your idea of converting a tow vehicle into a winch. I have often pondered this possibility myself, and even considered a design similar to yours. But not being a mechanic, I felt it would be wiser for me to pursue other areas of skyting research. I am glad to find someone who is currently exploring this stationary tow vehicle concept.

But as usual, when someone comes up with a new idea, I have a few questions I would like to ask. In the first place, what is this set up going to do to the vehicle? The system operates with one drive wheel not turning at all and the other spinning fast enough to pull the glider through the air. Normal highway vehicles are not designed for this type of operation. Will prolonged operation in this "winch" configuration eventually damage the differential of the tow vehicle?

A second question deals with the non-turning wheel. As the towline tension increases during certain phases of the flight, does it not eventually reach a value where the stationary wheel starts slipping? And how do you prevent slipping if you need more tension?

This leads us to another question, one dealing with tension regulation. How do you know how fast to pull the glider? What are you using as a tension guage? Are you using the speedometer to regulate the glider's speed? If so, then how fast do you tow in no wind conditions? And how do you compensate for wind gusts, wind gradients, and pilot maneuvering? In other words, how do you know how much to speed up and slow down in order to maintain constant towline tension?

Also, what are you using for a towline "guide" and how are you attaching it to your vehicle? If you are using an eye bolt, as indicated in the diagram, then doesn't this produce too much wear on the towline? And if you are using a pulley, what size are you using and how are you mounting it? How far does the "guide" need to be in front of the wheel to get good line feed action?

In your description, it sounds like you are using an automatic transmission. Have you ever tried using a standard? If so, which do you prefer and why?

In my opinion, the idea of a stationary tow vehicle is fantastic. Especially if it is as easy and practical as you imply. I am sure that I am not the only one interested in the result of your efforts. Please keep us informed of your progress.

Donnell
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PITCH CONTROL PROBLEMS
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1983/04-07

Dear Donnell,

Enclosed, please find $10.00 for my subscription to "Skyting". I have read three of your newsletters with much interest. I have been towing on both land and water for several years now using different types of releases on standard control bars. I have recently made a modified skyting harness using a Yarnall release on the keel and a release of my own design to auto release the bottom line. I use small sailing pulleys instead of rings. All releases stay with glider and pilot. I'm very pleased with the greatly improved control on tow. Thanks for giving the towing world a great new method for safer towing. The only point of concern I have is the lack of pitch control when using the botton line through the control bar which works great until you reach a very steep angle of the tow line. That hasn't been much of a problem so far with the power winch we're using but expect it may be when I start boat towing this summer as I get much higher and the tow line, with a fairly low tension, leaves the kite at a very steep angle. Having not seen your first publications, I do not know which method you suggest for using. Maybe you could republish the basic method you suggest for using the skyting harness in future publications for new users such as myself.

Thanks again,
Charlie Nordstrom
Tidewater Hang Gliding Association
Norfolk, VA
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1983/04-08

Dear Charlie,

Thanks for subscribing to the Skyting Newsletter, and I appreciate your telling me about the modifications you have made on your skyting system. Your rig sounds very similar to that used by Don Boardman III of Rome, NY. (See SKYTING NO. 8.) You may want to get with him and compare notes.

It is true that passing the lower bridle line through the control bar makes it hard to climb to high altitudes and passing it under the control bar makes it hard to stay at low altitudes. Therefore you need to decide at the beginning of the flight whether you want to tow to a high tow angle or stay at low altitudes. Most beginners prefer to stay low and, therefore, need to pass the bridle line through the control bar. Experienced pilots usually prefer to tow to high altitude and, therefore, need to tow with the bridle under the control bar. Yes, the bridle tends to make the glider want to climb during the early part of the flight when this configuration is used, but that is what the pilot wants. If this "pitch up" tendency is too strong to be controlled, then it means that there is something wrong with either the bridle or the towing system.

One possibility is that the bridle is too short. This means that the upper and lower lines come together at too great an angle and that the lower bridle line pushes up on the control bar harder than it ought to.

Another possibility is that the point of attachment is too high. Either the hang strap is too short and the pilot is hanging too high, or else the bridle is attached too high on the pilot's body. This would also cause a greater than normal upward pull on the control bar.

A third possibility (and a common mistake made by conventional tow pilots) is that the towline tension is too great. You said that you were towing with a power winch, but you did not say what your tension setting was. Since skyting requires the use of a weak link which breaks at approximately 200 pounds, then the tension setting for normal towing should be 100 pounds or less. (75 pounds seems to be a good setting.) If you are towing with about 150-200 pounds of tension, then the upward pull on the control bar will be more than you can overcome.

You suggested that I republish some of the basic methods used in skyting for new subscribers such as yourself. I do this from time to time when someone asks a specific question. (Such as the above discussion on the pitch-up problem.) But it is impossible to republish all of the basic or "important" material which occurs in the past issues of Skyting. In my opinion, essentially all of the material in the back issues of Skyting is "important" or I never would have published it in the first place.

Furthermore, skyting is developing very rapidly and new innovations and techniques are being introduced continuously. This does not leave much room in a five page newsletter for repeating previously published material. And the cost of small volume printing does not permit expending the size of the newsletter.

However, when skyting becomes a little better established and as the best innovative techniques become identified through experimentation, then I hope to publish a book on skyting which describes the latest state of the art. In the mean time I suggest Sandy Fransisco's back issues of Skyting (she also belongs to your Tidewater Hang Gliding Association), or else purchase your own copies. (A complete set only costs $10.00.)

I realize that you have considerable towing experience. However, it bothers me that you are using skyting components and making alternations without thoroughly reading the material in the back issues of Skyting. Skyting is more than simply using a center of mass bridle system. It is a completely different philosophy of towing. Mixing skyting components with conventional towing practices can be dangerous. (See "A broken leg in California" in Skyting No.11.)

The system you are using may well be the best towing system in the world, but don't you think you owe it to yourself to find out if your system has some of the same weaknesses which others have already discovered?

Sincerely,
Donnell
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1983/04-09

MOUNTAIN TOWING

Dear Donnell,

We are a hang gliding club with 30 members who are very interested in learning about your skyting techniques. We do have mountains, but the roads are very rough (or closed to access for us) and conditions on launch are frequently cross. We would consider tow launching at the base of 2000 to 4000 foot mountains during thermal cycles using the 500 to 800 feet gained by towing to allow us to catch lift.

We would like to obtain your skyting newsletters and would like to obtain any future issues you may publish. We will keep you informed with respect to our progress and would hope you will keep us up to date on skyting developments.

Joe Barfoot
Rio Grande Soaring Assn.
Las Cruces, NM
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1983/04-10

NEVADA TOWING

Dear Donnell,

I noted with great interest the article on Skyting in the Mar/Apr '83 WHOLE AIR MAGAZINE. Before moving west last year I was a member of the Indy Flyers, a group of tow flyers from Central Indiana area. We water towed extensively using a winch with 3000' of polyethylene rope (1/4" braided, 1100-1200 lb test) using the "Moyes" tow system, so I am quite familiar with lockouts! Also we did some land towing using a winch on a specially made trailer attached to a van where the observer(s) riding on the trailer had a remote throttle control. It is interesting that we never felt the need for a weak link using our Moyes gliders, however, occasionally a worn rope would break.

I am quite interested in your center-of-mass bridle system and would like to receive more information regarding this and the overall skyting system.

Steve Tullis
Carson City, NV
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[Tad Eareckson]

1983/05
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SKYTING NO.13
MAY 1983
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1983/05-01

Control Bar Floats For Water Towing

by Don Boardman

My towing experience started in Toronto, Ontario, on September 21, 1982. The school, High Perspectives, did an excellent job of taking a very fresh Hang I and, in a day, towing him to 1,800 ft above Lake Ontario. Part of what made the learning easy and the towing fun was the control bar floats that High Perspectives uses. High Perspectives developed the floats over several years. They consider them the best design available for deep water starts and landings. The floats allow a prone in the water start and a sea plane like landing ... level off hot about a foot above the water ... hold ... smooth, fun, prone landings.

High Perspectives had the floats for sale as of last September. I was told that after the present stock ran out they probably would not make more because of production costs. I do not recall their asking price for a set but it was not unreasonable for the time and cost involved in making a set. If you would like to purchase floats, if available, you can look up the High Perspectives ad in Hang Gliding magazine in the classified section under International Schools & Dealers, Canada. I highly recommend their towing instruction based on my personal experience.

Not having any extra spending money at the time and being reasonably handy, I decided to build a pair of the floats. This article illustrates the method I used. I hope the following contains sufficient information for a person who so desires to successfully construct a pair.

GENERAL DESCRIPTION

The floats are constructed out of sytrofoam, one-eighth and one-quarter inch plywood glued to the foam and the front and rear of the floats are protected by a one-quarter inch plywood cross piece. An axle sleeve is used to connect the float to the control bar of the glider. A float's angle of attack is adjusted and held by two cords which run from the ends of the cross pieces to a ring taped securely to the down tube. See illustration.

MATERIALS

1. Foam billet (dock floation) 42"L 24"W 8"H
2. One-eighth inch WATERPROOF plywood (I used scrap plywood planeling)
3. One-quarter inch WATERPROOF plywood
4. Paneling adhesive for foam
5. Resorcinol glue (waterproof)
6. Scrap control bar and cross bar tubing

TEMPLATES

I developed full size templates for all the plywood parts of the floats and saw guides. The saw guides are needed to the cut the foam into shape. You can do the same from the dimensioned diagrams illustrated here, or write me and I'll trace a full size set off my originals and send them to you.

Templates needed (paper or cardboard)
1 - nose-tail cross piece
1 - cross piece locking key
1 - axle support
1 - side panel shape

PLYWOOD SAW GUIDES

I made templates, which I will call saw guides, out of one-eighth inch plywood paneling. I clamped the guides to opposite sides of the foam block to guide my saw in cutting the rough foam block into shape. The saw guides are made one-sixteenth oversize all the way around. This allows the rough cut foam surface to be sanded smooth to the proper finished dimension. The dimensions given for the top-bottom shape are already a sixteenth oversize. The dimensions for the side panel shape are the actual dimensions for the side panels and will need to be a sixteenth oversized from the side panel template when making the side panel saw guide. You will need a pair of saw guides of the side panel shape and the top-bottom shape.

CONSTRUCTION

Become familiar with the total procedure before starting.

1. Use the templates to cut out the plywood pieces of the floats. Four, nose-tail cross pieces, eight locking keys, four axle supports, all of one-quarter inch plywood. Then, four plywood side panels from one-eighth inch plywood.

2. Using a guide, cut the foam billet into rough blocks. See "rough cut foam" for the dimensions. You will cut two control bar floats and a tail float from a billet 42" L x 24" W x 8" H. I clamped plywood strips to guide my hand saw onto the foam billet on either side of my saw line on both sides of the billet. This created a clamped on "mitter box". It gave me a clean straight cut.

3. Cut the "sides" off the floats' rough block. Use the top-bottom shape plywood saw guides clamped to the foam blocks as a guide in cutting. After the cuts have been made, remove the saw guides. I then used an electric sander with 80 grit paper to smooth and true the sides. The plywood side panels will be glued to this surface later.

4. Use the sixteenth oversize plywood saw guides, side shape, clamped to the sides of the float as a guide to cut the top and bottom surfaces of the float.

5. Use the side panel template to locate the center of the axle hole (over 15.5 inch, up 5 13/16 inch, see illustration) on one of the plywood side panels. Drill a small hole through all four side panels so that the centers will be aligned. Choose a drill size to correspond to a nail size you have handy. The nail will be used to align the axle support piece when it is glued to the side panel.

I chose to glue the axle supports to the side panels after the panels were glued to the foam as not to restrict the panel from curving and fitting to the sides of the foam. You may choose to glue the supports onto the panels before putting the panels onto the foam if you have limited clamping ability. Do not drill out the actual axle hole yet.

6. One at a time glue the plywood side panels to the foam block. Use an adhesive designed to bond paneling to foam insulation. You want a glue that acts like a contact cement. Apply to surfaces, press surfaces together, separate surfaces, let adhesive set on both surfaces. When the pieces are brought back together the second time they bond tightly and hold right away. I found masking tape helped to hold the ends of the side panels in place while the adhesive got a good grip, as these are stressing outward. Remember the top and bottom surfases have not been sanded yet so the side of the foam block is slightly oversized. Be sure to use the same alignment of the side panels on both sides.

7. With both side panels glued on, use an electric sander to reduce the rough sawed top and bottom surfaces to match the size of the side panels. This will leave very smooth, uniform, surfaces.

8. Cut the foam from the nose and tail to accept the quarter inch plywood cross pieces. Use the notches in the side panel as a saw guide.

9. Put the cross pieces in place in the nose and tail. Slide the locking keys into place, as far as they will go, and carefully mark the position of the notches which need to be cut out of the cross piece and the locking keys should allow the locking keys to go forward on the cross pieces so that the very front or back edge aligns with the front or back edge of the side panel. They then can marked and cut to follow the contour of the side panel.

10. Use resorcinol glue to assemble the nose and tail cross pieces with their locking keys.

11. Use resorcinol, glue and clamp the axle supports to the sides of the floats. Use a nail in the small holes drilled earlier in the side panels to keep the supports centered. You will also need to drill an alignment hole. nail size, in the center of the axle supports to accomodate the O.D. diameter of the float's axle. I would suggest a tight fit. I used a brace and bit to cut a one and one eight inch hold. I drilled through the plywood from one side and continued a bit more than half way. I then turned the float over and drilled from the other side. It helps if an observer can help you keep the drill perpendicular to the side of the float. Use an axle to clean out and align the hold through the foam.

14. Drill a small hole in each of the inside ends of the cross pieces to accomodate the cords which will be used to adjust the angle of the floats.

15. The final finish is your choice. The only thing I found to protect the top and bottom surfaces was resin designed for foam. It was to heavy in my opinion. My set of floats are entirely unfinished and with about eight hours in the water so far are just fine. I may get around to varnishing the plywood parts in time.

FLOAT AXLES

The float axles are pieces of old control bar or down tube tubing approximately fourteen and one quarter inches long. The tubing should have the same diameter and wall thickness dimensions as your control bar. The axles are inserted into the floats and held in place by two cotter pins. See illustration. The hole for the inside cotter pin must be centered to that the hole in the sleeve tube will line up, it must also be centered.

FLOAT ATTACHMENT

Attaching the floats to the control bar is accomplished by using a short length of tubing, as a sleeve, which will slip inside the end of your control bar about four inches and into the end of the float axle about four inches. Holes will be needed to accomodate the bolt in the end of your control bar and the inside cotter pin of the axle. Once the sleeve is in place in the end of the control bar, simply slide the float axle over the end of it and insert the axle's inside cotter pin.

If your control bar will not allow an inside sleeve as shown, you can set up the floats on a separate base tube and then bolt the "new" control bar directly to yours using the holes in your present control bar with extra long bolts. The thickness of two base tubes is a little awkward at first but this modification worked great for a Bobcat II.

ADJUSTING FLOAT ANGLE

Tape securely a ring to each down tube approximately sixteen inches up from the control bar as illustrated. Use cords running from the ends of the cross pieces to this ring to adjust the angle of the float. You will have to experiment a bit to find the proper angle, keeping in mind the angle the glider makes with the water during take-off and landing.

THE TAIL FLOAT

Nothing fancy here. High Perspectives uses a commercial cylinderical one. I simply use a block of foam 24" L x 10" W x 8" H. A bit large, but it keeps the end of the keel out of the water no matter what. Take an old piece of cross bar, which fits either inside or outside of your keel tube and "insert" it into the foam block. I cut saw like teeth in the end of the tube and two of us literally push-sawed the tube 90% of the way into the block. A very tight fit, watch for alignment. A one bolt attachment can be used or if you don't want to drill a hole in the end of your keel, use duct tape at the tubing overlap point.

USING THE FLOATS

The take-off using the floats is very easy. The pilot moves out into the water and gets settled prone with the control bar under his (or her) chest. When everything is ready, the pilot extends his arms fully and yells "hit it"! When the glider breaks the surface of the water, which is a matter of a few seconds, the pilot pulls the bar back and proceeds as in a normal tow.

The boat starts out easy to get the glider just moving. It then accelerates to create an even pressured "pop" of the glider out of the water. This is not the traditional use of the term pop as in pop start. You want enough acceleration to get the floats to plane off quickly so they don't plow through the water. Once the glider is out of the water, the boat will continue to accelerate and follow standard towing - skyting procedures in regards to towing speed, etc.

The landing, probably the most fun, is described in the first paragraph of the article ... have a wet and wild time in that hot summer AIR.

I hope I have not left anything critical out and wish you luck in building a set of floats. Take your time and I'm sure you will be pleased with the results and their performance. Feel free to call or write if you have any questions.

Don A. Boardman III
6433 Karlen Rd.
Rome, N.Y. 13440
(315) 339-0009
+
CONTROL BAR FLOATS FOR PRONE DEEP WATER STARTS AND LANDINGS
+
SLEEVE

8 1/2"
+
AXLE

14 1/4"
+
ROUGH CUT FOAM

42
24
32
10
12
12
+
CROSS PIECE

11 1/2 x 1 1/2"
+
LOCKING KEY

ACTUAL SIZE
+
AXLE SUPPORT

2 1/2" dia.
+
SIDE PANEL SHAPE

0
5
9
14
15 1/2
20
26
31

7 3/4
3
1 1/16

7 5/8
8 13/16
8 3/4
8 1/8
5 13/16
6 3/4
4 5/8

1 3/8

1 1/8
+
TOP-BOTTOM SHAPE

7 3/4"
31"
7 3/4"
8 1/2"
11 1/4"
12"
11 1/4"
8 1/2"
*
1983/05-02

YAW PROBLEM SOLUTION AND TOW CHAMPIONSHIPS

Dear Donnell,

I would like to comment on your solution to the adverse yaw problem. My experience towing a Mosquito leads me to believe that most of the yawing can be attributed to pilot over-control on early flights. My first Skyting found me yawed 45 degrees to both sides of the tow line in rapid oscillations (Pilot induced oscillations).

Now, with more experience I find that the yaw problem is not nearly as bad as I originally percieved. When I relaxed and let the glider have its head, there is some yaw (5 degrees - 10 degrees) but it will dampen out itself!

From watching several others tow and fly my Mosquito, I have determined that there is a great deal of adverse yaw prior to turning. In fact my recommended turning method also works on the double surface floating cross-bar gliders I have flown (Duck, Demon, Meteor).

While your solution may eliminate any yaw, a better solution is to use the gradual advancement provision, use less yaw sensitive gliders for beginners, and relax control inputs while on tow.

Finally, I have accepted a job with the Fort of the Osage Water Show on Lake of the Ozarks, MO. Since I will be doing some of the flying in the show, I hope to really advance the Skyting art. Weather permitting, we will fly every day except Friday. I'll keep the Skyting Newsletter informed of our progress.

Oh, there is a "Delta Tow-Glider Championships" scheduled for September 19-18 at Cypress Gardens. According to World Water Skiing the man to contact is Lynn Novakofski (813) 324-2111. I am planning to go and show off skyting. How about any of you other Midwest pilots, want to go and share costs?

Roger Coxon
12844 Huntercreek Rd.
Des Peres, MO 63131
(314) 965-9021
*
1983/05-03

A SKYTING BRIDLE USED IN MISSOURI

by Roger Coxon

Reading about accidents in Skyting is not my idea of fun. In fact, I hate it. Especially when some of the accidents might have been avoided if I'd written this earlier. So all of you safety conscious Skyters and potential Skyters listen up.

First, a new Skyting Law: The pilot should at all times be able to, without fumbling, positively release the bridle. No offense, Donnell, but the idea of reaching for the release on my stomach while in some wierd attitude doesn't appeal to me. If Rich Pfeiffer and his friends had used my system on their Skyting system, when the pilot lost the control bar on launch, he would have been released immediately and dumped the nose. He would then have cussed me as he bought two new down tubes, rather than cussing Skyting on the way to the hospital.

My release system has a loop around my wrist at all times, requiring only a quick tug to release the top, with the bottom following on auto-release. (See Figure 1.)

Having the auto-release line on the lower half of the bridle helps prevent premature auto-releasing. The geometry of the bridle makes the lower half longest at launch. (Sit and think about that till you're sure you understand, and if you don't understand, call/write me and I will expound.) This allows you to tow under the Skyting criteria all the time. I don't care about the upper line hitting my head - I just skew my body so the center of gravity stays the same while moving my head out of the way. If you are not good enough to fly this way, you've exceeded the Gradual Advancement Provisions (Skyting #1) and are towing at too high a tow angle too soon, so get back down and learn it right!!

I also use two ring releases, and they are very positive, while providing a more than adequate leverage advantage for Skyting applications.

One final thought: Skyting is the infant brother to hang gliding. All of us practicing it are test pilots. Hopefully my method is a step in the right direction, but if you disagree, write to Skyting and tell me why and what you'd do differently.

Fly free and happy!
+
Figure 1

WRIST RELEASE LINE
AUTO RELEASE LINE
RC '83
*
THE FRENCH CONNECTION WITH SKYTING
*
1983/05-04

Dear Donnell,

Coming from the flatlands of Indiana I have been involved with towing for a number of years. My baptism was with the Moyes system and boat towing, then two years ago with a motor winch and Yarnall Bridle. I can honestly say I was not fond of either system and probably would not tow again if I had to use them.

I read your first SKYTING article in Hang Gliding and meant to write to you for more information at the time but never did. This past winter, I and another tower began to think of towing modifications and happened on the Mar/April issue of WHOLE AIR Magazine, and your article. We would like more information please, i.e. angle of attack, length of bridle, etc.

In closing I would like to show you a crazy idea I came up with in an attempt to prevent the initiation of a lock-out. It has not been tried but I would like your impressions.

If this is dumb, trash it.

George J. Moore
Indianapolis, Indiana
+
VIEW FROM FRONT OF GLIDER TOWARD REAR

CROSS BAR
KEEL
FRENCH CONNECTION IN PLANE OF TOP BRIDLE LINE

TOWLINE FORCE DISPLACED TOWARD TOW LINE, WOULD IT HELP TO BRING THIS WING DOWN AND REDUCE LOCKOUT TENDENCY?

GLIDER WANDERS TO ITS RIGHT
*
1983/05-05

Dear George,

Thank you for writing and for sharing your idea. I had never thought of using a French Connection in the manner you described. The idea shows promise, and I believe it would have exactly the properties you describe.

However, it is not the keel attachment point that causes lockouts and loss of control, but the base tube attachment point. So I do not believe that the French Connection could possibly compensate for the base bar connection. In other words, the French Connection cannot by itself, correct the lockout characteristics of conventional towing.

In the case of a skyting system, the towline is already attached to the center of mass of the glider. If a French Connection were used, it would effectively put the tow force through a point above the center of mass. This would possibly make the glider roll unstable. I.e. if a gust of wind picked up the left wing, the tow force would shift over to the right wing and amplify the right roll tendency. If the tow force were large, the glider would turn right. If it did not roll too far, then it would turn until the towline pulled left. Then a left roll and left turn would result. The pilot could find himself in a over controlled oscillation similar to that already reported by some pilots. (See other issues of SKYTING.)

In SKYTING NO. 12 it was pointed out that cross bar towing may be able to eliminate the adverse yaw problem. If it doesn't, then perhaps a modification of your idea will help. Time will tell.

Donnell
*
1983/05-06

CONCERN ABOUT YAW PROBLEM SOLUTION

Bill Chambers called and expressed some concern about the proposed solution to the adverse yaw problem. Specifically he wonders whether pulling on the cross bar will tighten one of the sails so as to cause a roll opposite to the tow line. He fears that such an adverse roll will cause the glider to tend to lockout.

Although I still believe my original analysis of this problem is correct, I feel that you should be made aware of Bill's concern so that you can take it into consideration before you decide to test the theory.

Donnell
*
OVER OR UNDER THE BASE-TUBE
*
1983/05-07

Dear Donnell,

I am planning on purchasing a winch when I return to the USA this summer. I am very interested in your towing methods. Would you please send my any written material you have on your attempts at towing?

I have just read the article in Whole Air Magazine which very briefly describes a bit about towing. There seems to be a discrepancy between the pictures and the illustrations. The pictures show the lower bridle passing over the base tube on the control bar while the illustrations show the lower bridle parts to be under the bar. Which is correct?

A. B. Duvall
Lusaka, Zambia - Africa
*
1983/05-08

Dear Mr. Duvall,

In answer to your question, the pictures were illustrating the development of an air-to-air towing system where the glider is only slightly above the tow plane. In this case, the lower bridle line should pass through the control bar. (See the Fig. 5 in the article.)

All of the other illustrations pictured towing from the ground or water. Here the glider will be towing to a high tow angle and needs the bridle line below the control bar. If the line passes over the base tube, then it will prevent the glider from climbing to high altitudes.

Donnell
*
1983/05-09

WET PARACHUTE PROBLEM

I have a problem I would like to get some feedback on. Our lake has virtually no shore so our prone in and out of the water is most practical besides being great fun. My concern is how do I carry a parachute given this type of launch without getting it wet? Any ideas out there? Not being able to carry a chute will surely put a damper on cross country flight.

Don A. Boardman III
Rome, N.Y.
*
1983/05-10

Hey, any of you guys out there have a solution to this problem? Ed.
*
*

[Tad Eareckson]

1983/06
*
SKYTING NO.14
JUNE 1983
*
DEAR DONNELL
*
1983/06-01

SAFETY PODS ARE NEEDED

Dear Donnell,

I have read the Skyting articles in March/April - July/August 1982; March/April 1983 Whole Air Magazine and May 1983 Hang Gliding Magazine.

In the Skyting system the emphasis is on safety and as such, a safety pod unit could become a safety component of a Skyting system.

More safety pod comments: There are various means of getting in and out of a safety pod unit. Recumbent as well as prone pods could be designed. All safety pods could have open structure at top for wind-in-the-face flying, with standard helmets being worn inside the safety pods. Plastic foam mold inserts could be used as part of a safety pod. There is also the possibility of using launch/landing wheels and skids on the safety pods.

Since 1979 I've been trying to interest the foot launch hang gliding community, etc., in safety pods - July/August 1981 Whole Air Magazine p. 8,9 - Nov. 1981 Hang Gliding Magazine (Protective Flarings) p.5 - plus pod papers to many people, etc.

As I'm no practical mechanic, I've sent out the safety pod ideas to those individuals and organizations whom I thought might want to fabricate such safety pods, so if you know of anyone who'd like to fabricate safety pods, please bring the safety pod ideas to their attention.

Edwin G. Sward
Worcester, Mass.
*
1983/06-02

WANT TO KNOW MORE ABOUT SKYTING

Dear Donnell,

For two years now we have been Tow Launching here at Lake Livingston, about 75 miles north of Houston. The method we use, I believe, is called Pop Launching.

To my knowledge, we have yet to complete a full weekend of flying without at least one lockout. Splash!

Now you know why I am writing, I would like to ask my questions. The kite is a Moyes Midi, equipped Cypress Garden style, using a bridle with an upper and lower release. Of course the Pop Launch requires Stainless Steel down tubes, etc. The boat is a V haul 17' equipped with a 115 H.P. outboard.

We would greatly appreciate any information you could provide that would enable us to convert to the Hewett Bridle. It sure sounds like a cure for my severe case of Lockout-phobia.

Bob Casto
Spring, TX
*
1983/06-03

Dear Donnell,

Finally a reasonable system of towing. It really looks great. It must, if it has a conservative mountain man longing for open spaces.

Would you please send me information on how to obtain the SKYTING literature and instructions for the skyting bridle.

Jay Andriot
Vienna, Virginia
*
1983/06-04

Dear Donnell,

I am a Hang 4 pilot with about 200 tows over water. I am interested in towing this summer and would like to know more about your tow system.

Ted Hocking
Boston, Mass
*
1983/06-05

Dear Donnell,

It was with great enthusiasm that several of us read about your skyting system of towing. Please rush us construction plans, materials needed, etc. or anything else we might need.

Les Stauffer
Echo, Ore.
*
1983/06-06

Dear Donnell,

Please send us more information about Skyting. With huge frozen lakes during 5 months of the year we would be able to keep our pilots more proficient with your method.

Mike Jarster
Arctic Sparrow Aircraft
Anchorage, Alaska
*
1983/06-07

Dear Donnell,

Please send me all the info on SKYTING and towing. I operate a hang glider and ultralight school and would like to start towing. I'll be in the USA in July and might come to Texas.

Tommy Namias
Auckland, New Zealand
*
1983/06-08

Dear Donnell,

I have just finished reading the May issue of Hang Gliding Magazine and am now aware of your technique regarding your design of a new concept in towing. Thank you so much for taking the time to develop a "lockout-proof" towing bridle. As you probably know, you have revolutionized towing so that it can be relatively safe.

In December of 1981 I tried my hand at towing using a Yarnell bridle. I was a Hang 1 and figured I shouldn't have any problem, right? WRONG? I locked out at thirty feet, crashed, and broke my back (compression fracture T-5). Since then I have not towed, but continued to foot launch off of small hills. Now you know why I am so excited after reading your articles (articles about your bridle). I have spoken with George Moore who is president of our club here in Indianapolis, and he said that one had to subscribe to your publication before ordering one of your bridles. Well, I am certainly in favor of anything that can help make this sport safer.

Can you send me information regarding your publication, subscription rate, and pricing of your bridle and you to order?

Preston J. Tuchman
Indianapolis, IN
*
1983/06-09

Dear Donnell,

A member of our club showed me your first Skyting Newsletter and generated interest among a few of us who might find your information useful. Could you please send a complete set of back-issues of the "Skyting Newsletter". We will keep you informed of any developments of skyting in this area if it catches on. Also I will inform our members of your efforts and ask them to buy their own copies of your newsletter and also to subscribe to the publication.

Bob Havreluk
S.N.Y.H.P.A.
Millwood, New York
*
1983/06-10

Dear Donnell,

I represent a small club of Hang Glider pilots in Southwestern Ontario, of around fifty pilots. At our last meeting the subject of SKYTING was brought up and it was requested of me to find out more on the subject on behalf of the club.

I learned of your address from a small group near Toronto currently using your system, so I am writing to you to request information on the skyting system. Please send us any information you can on how and where we can purchase the system or its parts, instructions on learning its use and suggestions and comments from others who are using it.

Our area is painfully void of hills large enough to make soaring easily accessable to our pilots and skyting appears to be an exciting and viable alternative to "getting up".

Kevin Thomson
Kitchener, Ontario, Canada
*
1983/06-11

Dear Donnell,

The artilce in Whole Air and some amazingly exciting stories from some of our fliers in Eastern Canada have convinced a small group of western prairie pilots that SKYTING is the safe towing method we've been waiting for. As a result the directors of the Manitoba Hang Gliding Association have instructed me to secure a subscription to SKYTING magazine. (A safe pilot is a well-read pilot.)

Rick Hay
Manitoba Hang Gliding Assn
Winnipeg, Manitoba, Canada
*
1983/06-12

Dear Donnell,

I quit towing in 1977 after my first lockout. A quick release and being over water prevented damage.

However, living several hours drive from good flying sites has really put a crimp in my air time.

I read articles by Whitman and Phillips in my May H.G. Mag. Now I'm getting interested in trying it again. But first I would like some additional information as recommended at the end of the Phillips article.

Please send me whatever information you can to make my attempts safe and enjoyable, including information on where to buy the necessary release mech.

I fly a Raven 209. Other local flatland flyers who will chip in on the tow system fly Ducks and Harriers.

Gary J. McCahill
Waterford, CT
*
1983/06-13

Dear Donnell,

Thank you for sending me SKYTING NO. 1. I found it fascinating. I expect a towing system to cost over $1,000 and am glad to see that I can get in well under that figure. Please send me all of the back issues and sign me up for a subscription to Skyting.

I look forward to reading and rereading all of the Skyting articles.

Jay Andriot
Vienna, Virginia
*
1983/06-14

KANSAS CITY FLYING

Dear Donnell,

We in K.C. mostly fly the 200-300 ft Missouri River Ridges. We have experience with several kinds of towing, but have found it to be very dangerous. We will keep you notified in the event we learn something of interest. Our weather has been such that very little flying has been done in over a month. Seems like it rains all the time. (Both this spring and last spring.)

Ted Gilmore
Mission Hills, KS
*
1983/06-15

COLORADO OVER-DEVELOPMENT

Dear Donnell,

Thanks for sending the Skyting Newsletters. Sounds like your system is just what I have been looking for. We plan to begin water towing as soon as the weather warms a bit. After we feel we have mastered water towing we plan to progress to land towing.

During spring and early summer the mountains of our state become unflyable due to overdeveloped clouds and rain showers, which happens while the eastern plains bask in sunshine and perfect cloud streets. We hope towing will allow us access to those super highways in the sky.

I will keep in touch when I feel we have something to offer you and your readers.

Dave Krattli
Lakewood, Colorado
*
1983/06-16

MORE FROM AFRICA

Dear Donnell,

Thanks for the super-prompt reply and the sent information.

As I said in my first letter (Skyting No. 13), I'm bringing back a kite or two when I come. As far as I can tell, there are no hang glider pilots in Zambia now. I have met some in Zimbabwe who will be anxious to get the information you sent me. I'll work out some kind of deal on the money.

I will be in the U.S. this summer and will try skyting with Garry Whitman of Oklahoma. I won't be able to get to Kingsville, it is just too far out of the way and I only have 8 weeks home leave.

I'll keep you informed about the progress we make.

Terry & A.B. Duvall
Lusaka, Zambia, Africa
*
1983/06-17

MORE FROM GUATEMALA

Dear Donnell,

I have your August 14 letter in front of me (Skyting No. 5.), whereby you kindly sent me your Skyting issues.

Guatemala is a mountainous country and we have volcanos that are up to 12,000 feet high from which to fly. However, getting up to many mountains is somewhat problematic (rains wash out the roads, etc.) and we would also like to fly near the ocean, where it is flat. For this reason, we are very interested in your system.

I have followed its development very closely (all the way up to articles in Whole Air and even Gil Dodgen's "A Note on Towing" in Hang Gliding. Your system has come a long way into acceptance and I congratulate you for it.

Fernando Linares Beltranena
Guatemala City, Guatemala
*
1983/06-18

CANADIAN INNOVATIONS

Dear Donnell,

We've only had about 7 flights on the skyting system. The problem has been weather. Perhaps you could put in a few words on our behalf to the One responsible. But, even with our limited experience, we are very encouraged. Looks like skyting will really make hang gliding feasible in this area.

Tim Churchill tells me he has already described our car/winch system to you. Otherwise, our system is very similar to that described by Dennis R. Owen on page 5 of Skyting # 10. I am especially pleased with his release arrangement because you never have to reach for it. Because we're still inexperienced tow pilots, aborted launches are common. Cutting free is just a matter of moving your arm.

One departure from the system described in Skyting #1 is the elimination of the 100 foot leader. I didn't like the idea of having to drag 100 ft of strong rope until landing. The leader seems to be needed because most people use elastic rope for the bridle, which tends to fly back in the pilot's face when the weak link breaks. The solution is to use a non-elastic bridle. We use 1/4 inch polyester yacht braid. The weak link connects the bridle directly to the towline. We've had several weak link breaks, with no tendency for the bridle to fly back.

One idea I'd like to try, but haven't had a chance to, is a simulator for training purposes. I think it would be possible to set up a glider on a small utility trailer, with a skyting bridle and restraining lines on the nose and wings. These restraining lines would be long enough so the student would "fly" the glider when the trailer was towed, but would prevent any really radical attitudes. The instructor would ride on the trailer with the student, able to give advice and physical assistance at all times. This would also greatly reduce student fatigue, as carrying the glider around would be almost eliminated.

Finally, sorry to hear about your recent accident. Hope the arm heals quickly. In my opinion, your accident, and the one described by Rich Pfeiffer, do not reduce my confidence in the skyting system. My own experience makes me believe the basic concepts are sound. In fact, skyting may be safer than foot launched flight. Please keep printing accident reports- maybe some can be prevented this way.

Tom Bushell
Halifax, N.S. Canada
*
1983/06-19

MORE ON THE STATIONARY TOW VEHICLE

Dear Donnell,

I'm glad to hear there is no extra expense when mailing first class to Canada, and I think you should include this fact in your newsletter for the benefit of the rest of the Canadian flying community.

In response to your letter (Skyting No. 12), our first attempts at skyting were in 10 to 15 mile per hour winds. Perhaps I made a mistake in my first letter. Did I mention we tried with little success to kite the glider, before trying the winch. Once the winch was used, we found the launching to be quite easy.

To answer your questions concerning the stationary tow vehicle:

1. Normal highway vehicles are in fact built to handle one wheel turning while the other is not. Our experience is that the speedometer reads fairly close to the actual glider speed. The stress applied to the differential would be less, in fact, than the stress incurred while spinning your wheels in the snow. As long as the gears are in decent shape and well lubricated I can't see any problems with this.

2. The tension on the turning wheel should at some point overcome the restriction on the other wheel were it not for the weak link. Since this limits the tension to 200 lbs, the only time it should be a concern is when launching on snow or ice. To check this unknown value simply put you wheel wrench on a lug nut on the hub and jump on it. If you cannot turn the wheel in this manner, then you have no problem. I usually lower the vehicle down once the spool is on, to apply more weight to the other wheel. This will also lower the center of gravity and make the STV more stable. As I usually winch with the vehicle at an angle to the towline for better visability, most of the pull on the winch is sideways. The car is more stable this way.

3. As I mentioned earlier, the speedometer is a good reference for winch speed. We have not, as yet, developed a tension device but we are working on it. In no wind, I would suggest a tow speed of 5 mph faster than stall speed. From this speed you could speed up or slow down to suit the pilot.

4. At present we are using a simple eye bolt. A pulley would be better but we have to find a way to guide the line through the pulley. Once a tension gauge is used, it will probably include a pulley. The eye bolt is attached about 2' from the spool. Most of the wear seems to be in the eye bolt. The line is actually wearing a groove in it. The tow line doesn't seem to be wearing but the eye bolt is going to have to be replaced by a pulley.

5. Yes, we are using an automatic transmission and I think it is best designed for winching. By applying the brake and revving the engine slightly prior to launch, I am able to slowly release the brake and allow a smooth transition. A standard transmission is not quite so easy. I would suggest applying the emergency brake while revving the motor and releasing the clutch. Upon launching, the brake should be slowly released. As you can guess, this is hard on the clutch. If you can, use an automatic.

Tim Churchill
Armdale, N.S., Canada
*
PLEASE BE MORE CAREFUL
*
1983/06-20

Dear Donnell,

I was very sorry to learn about you breaking your other arm.

Please try not to be so pioneering in the future. The sport cannot afford to lose a man of your intelligence. Keep up the excellent work.

If you still feel the need to experiment with tethered towing, I would recommend that you do it firstly in 20+ mph winds that are very smooth. As you found out, you cannot afford to stall close to the ground.

Chris Sali
Olds, Alberta, Canada
*
1983/06-21

Dear Chris,

Thanks for writing. I appreciate your concern and your words of advice. Rest assured that I plan to fly much more conservatively in the future.

Donnell
*
PLANNING TO AIR TOW
*
1983/06-22

Dear Donnell,

The article in Whole Air was inspiring.

I've been free flying off and on since 74 and now also have a Kasperwing motorglider. I'm all set up for towing with the K-wing, but haven't yet because of the weather. Being a 1500 jump skydiver, I'm using the 3-ring system, and will be towing a floater to start with.

Erling Olson
Summer, Washington

((Sumner))
*
1983/06-23

Dear Erling,

Please remember that air-to-air towing is still very much in its infancy. You will be acting as a test pilot and pioneering the field. In other words, what you propose is, in my opinion, considerably more dangerous than other forms of skyting. What worries me the most is whether or not your two aircraft are compatible. (Does the Kasperwing have sufficient power? If so, does it fly too fast for the "floater"? Do you have skilled pilots for both craft?)

Please learn all you can before going ahead.

Donnell
*
RUBBER SLEEVES AND ROPE SOARING
*
1983/06-24

Dear Donnell,

I wrote earlier (See SKYTING NO. 11) that the plastic sleeves on the releases broke when dropped in cold weather. Instead of the plastic, I first made a one inch wide rubber band out of bicycle innertube. This was to give traction to the hose clamps that I put on over the innertube. The hose clamp serves as an anchor for the auto-release line on the top release and a knob on the lower release for easier handling. I hack sawed off the hose clamp screw heads on both releases. Then I slid a wider section of innertube over the hose clamps so that the auto-release line couldn't shorten itself by hooking on the clamps.

I went to Lake Superior near Duluth, Minnesota (a lot of ENE winds there, straight down the length of the lake). This day we were blown out - snow and 25-35 mph winds. So no rope soaring. Even if the wind evaporates, we have 300' from water line to tree line. I was thinking of staking out at the water line and take off with about 250' of line. Once up, a person at the stake would let out line. What do you think? I would guess a longer line to start with would be better but topography doesn't permit.

No Skyting lately, the ice is still melting on the lakes.

Bill & Terry Cummings
Hoyt Lakes, MN
*
1983/06-25

Dear Bill & Terry,

I believe 250 ft is a little short, but kiting can be done on such a line. There will be little room for maneuvering on the line, and the wind will need to be ideal.

I would not recommend lengthening the towline after the pilot is airborne, or the pilot could run into trouble penetrating. You can imagine what would happen if the pilot allowed himself to get too low on a towline reaching beyond the trees in winds which are soarable. One way you could possibly double your rope length is to run it through a pulley and attach it to a car. Anchor the pulley at the shoreline and launch the glider. When the pilot is soaring well, slowly back up the vehicle and let line out. The driver can watch the pilot and if he gets too low over the trees, he can drive forward giving him air speed to gain altitude and pulling him forward toward the landing area. But even this could be dangerous if the car dies. The pilot could also die.

Donnell
*
1983/06-26

GETTING AIR TIME

Dear Donnell,

Thanks for sending us the little reminder to renew our subscription to renew our subscription to SKYTING. We've enjoyed reading and re-reading each copy we get, and we trust the future articles will be as informative and new-idea-giving as the past "letters."

The lakes, up here in the Great North Country, have been thawed for a couple of weeks, but still are too cold to dip a toe into. We are hopeing, with the help of a wet suit, we'll be spending a good part of Sat. at the lake, skyting behind our boat.

Bill tried flying in the school yard, across from our house, a couple of days ago. Don, our partner, was the tow vehicle! Don would pull the rope, Bill would hop around, float a bit, and come down, while Don continued pulling the rope.

I really can't say what kind of grounded bird the scene reminded me of. I can tell you, though, that I wasn't the only one on the block laughing. What a sight!! The things a pilot, starved for air time, won't do!!

We hope to be getting some info to you on our boat Skyting after Saturday if the weather holds.

Oh! Just remembered - it's opening day for the fishing season in these parts. There are usually 100+ boats on our local lade on the above mentioned occasion. I guess Saturday will be a lake-hopping day. Which of the area lakes has the fewest fishermen? Round and round we'll go and where we'll stop, nobody knows!

Why would a body want to fish when one could FLY?

Bill & Terry Cummings
Hoyt Lakes, MN
*
PITCH CONTROL PROBLEMS
*
1983/06-27

((Duplicate from 1993/04.))

Dear Donnell,

Enclosed, please find $10.00 for my subscription to SKYTING. I have read three of your newsletters with much interest. I have been towing on both land and water for several years now using different types of releases on standard control bars. I have recently made a modified skyting harness using a Yarnall release on the keel and a release of my own design to auto release the bottom line. I use small sailing pulleys instead of rings. All releases stay with glider and pilot.

I'm very pleased with the greatly improved control on tow. Thanks for giving the towing world a great new method for safer towing. The only point of concern I have is the lack of pitch control when using the bottom line through the control bar which works great until you reach a very steep angle of the tow line. This hasn't been much of a problem so far with the power winch we're using, but expect it may be when I start boat towing this summer, as I get much higher and the tow line, with a fairly low tension, leaves the kite at a very steep angle.

Having not seen your first publications, I do not know which method you suggest using. Maybe you could republish the basic method you suggest for using the skyting harness in future publications for new users such as myself.

Charlie Nordstrom
Norfolk, VA
*
1983/06-28

((Duplicate from 1993/04.))

Dear Charlie,

Your rig sounds very similar to that used by Don Boardman III of Rome, NY. (See SKYTING NO. 8.) You may want to get with him and compare notes.

It is true that passing the lower bridle line through the control bar makes it hard to climb to high altitudes and passing it under the control bar makes it hard to stay at low altitudes. Therefore you need to decide at the beginning of the flight whether you want to tow to a high tow angle or stay at low altitudes. Most beginners prefer to stay low and, therefore, need to pass the bridle line through the control bar. Experienced pilots usually prefer to tow to high altitude and, therefore need to tow with the bridle under the control bar. Yes, the bridle tends to make the glider want to climb during the early part of the flight when this configuration is used, but that is what the pilot wants. If this "pitch up" tendency is too strong to be controlled, then it means that there is something wrong with either the bridle or the towing system.

One possibility is that the bridle is too short. This means that the upper and lower lines come together at too great an angle and that the lower bridle line pushes up on the control bar harder than it ought to.

Another possibility is that the point of attachment is too high. Either the hang strap is too short and the pilot is hanging too high, or else the bridle is attached too high on the pilot's body. This would also cause a greater than normal upward pull on the control bar.

A third possibility (and a common mistake made by conventional tow pilots) is that the towline tension is too great. You said that you were towing with a power winch, but you did not say what your tension setting was. A good value is about 75 pounds. If you are towing with about 150-200 pounds of tension, then the upward pull on the control bar will be more than you can overcome.

I realize that you have considerable towing experience. However, it bothers me that you are using skyting components and making alternations without reading the material in the back issues of SKYTING. Skyting is more than simply using a center of mass bridle system. It is a completely different philosophy of towing. Mixing skyting components with conventional towing practices can be dangerous. (See "A broken leg in California" in SKYTING NO.11.)

The system you are using may well be the best towing system in the world, but don't you think you owe it to yourself to find out if your system has some of the same weaknesses which others have already discovered?

Donnell
*
1983/06-29

RAMBLING

This issue of SKYTING marks the beginning of the second year of regular monthly publication. One year ago, I really had no idea of what I was getting myself into. I did not realize how much time and effort was required to publish a newsletter on a regular monthly basis. Well, now I know.

At that time I felt there was a desperate need for a means of communicating ideas and information on skyting during its developmental period. Today I feel that this need still exists, so here we go on a second year.

The first thing I would like to do is to thank all of you who have renewed your subscription to the newsletter. I find it, personally, very encouraging. The fact that you are willing to plunk down your hard earned cash a second time indicates to me that you feel you got your money's worth the first time. The money, of course, just bearly pays for the publication and mailing costs, but your encouragement provides the incentives to keep on going.

Speaking of "keeping on going", you may have noticed that this issue of SKYTING is somewhat later than usual. I hate to give excuses, but the fact is that I have been out of town for most of the last month and a half. And when I got back home, my mail box was filled with inquiries for more information on skyting. This influx of communication is primarily due to recent articles in both Whole Air and Hang Gliding magazines.

There is no doubt that skyting is beginning to catch on like fire. I just hope it doesn't catch on so fast that someone gets "burned". Well, anyway, it has taken me a while to catch up on all my "overdue" communication responses.

Fortunately - or unfortunately, depending upon your point of view - I will have a little more time to do some writing during these next few months. Seems like the doctor has decided to keep me grounded at least until September. Oh yes, my arm is out of the cast (after two and a half months) and it is healing properly - but slowly. The latest X-rays did not show the new bone growth to be as solid as the doctor would have liked, so he told me not to lift anything heavier than 25 pounds until further notice. This means that I cannot skyte, but I can type.

I can also drive, so if anyone is interested in coming down to Kingsville for some skyting, I'd be more than happy to serve on the ground crew. However, you will have to do all the flying. Sorry about that, but but I think you can handle it.

Actually, Helen and I have had two sets of visitors here in Kingsville since I got my arm out of the cast. Carl Geers of Austin, TX, and Ann Hoehn of Graham, TX, came down last May 19-21. They not only had fun skyting but they also helped my evaluate the latest model skyting bridle we are working on. (See next month's issue of SKYTING.) And on July 7-8, Mike and Marsheila Haley of Lubbock stopped by Kingsville on their way back home after flying in the Monterrey mountains of Mexico. Mike did some skyting and showed us some of the innovations the Lubbock skyters had done. Mike has agreed to write an article on the Lubbock system and describe his method of supine skyting. Both of these visits were not only enjoyable to all concerned, but were also very fruitful as far as skyting development in concerned. Without someone like "Red" Wylde to fly with on a regular basis, I have to depend upon such visits to stimulate ideas and evaluate modifications. I only wish more of you could come down here for a visit.

In fact, Helen and I started to organize a Skyte-In this year similar to the one last year (See SKYTING No. 4) in order to encourage more of you to come see us. But without a nucleus of local skyters here, we really have no idea as to how much interest there might be in attending such a skyte-in, what kind of activities to include, and when to schedule such an event. Considering the distance most pilots would have to travel to get here, we may have already waited too late to do anything this summer. But if there is enough interest, perhaps we can do something this fall. Let me know what you think. Personally, I believe it is about time we started having some kind of skyting get together somewhere - if not Kingsville, then somewhere else.

Speaking of "letting me know", I hope you realize that there are a lot of you out there who have not kept your part of the bargain. I promised to put out the Skyting Newsletter, and you promised to keep me informed about your skyting activities. Don't you think it's about time for you to start sharing your experiences with others? In fact, I would like to ask all of you - even those who have written to me recently - to join me in an effort to gain a clearer picture of the current status of skyting development. If you are willing to help, please fill out the following form and send it to me, or write me a letter describing your skyting system. Encourage your friends who skyte to do the same. (You have permission to copy this page of the newsletter.) Perhaps together we can gain a better understanding of where skyting is and where it is going.

Once more, let me express my thanks for your support. Without your help and encouragement, skyting would not be where it is today.

Donnell Hewett
*
1983/06-30

STATUS REPORT

(Circle the appropriate material or fill in the blanks.)
Name
Address
EXPERIENCE:
Hang Gliding: years, flights, air hours, USHGA Rating
Conventional Towing: years, flights, hours, ft altitude gain
Skyting:
years, flights, hours, ft altitude gain
Learning method: Self-taught? Friend's advice? Professional lessons?
Land tow? Water tow? Air tow? Moored kiting?
Accidents:
Injuries:
YOUR CURRENTLY PREFERRED SKYTING SYSTEM:
Type: Land tow? Water tow? Air tow? Moored kiting?
Towline:
ft non-elastic, ft elastic
Bottom emergency release? Drag Chute? Leader at top?
Bridle: Home make? Purchased? Slip rings? Pulleys? Nylon? Other?
Auto-release: Bottom? Top? Bridle falls away? Bridle stays with glider?
Releases: Original "horse bridle"? 2-ring? 3-ring? Sail plane? Other?
Release activation point: Pilot's body? Pilot's hand? Control bar?
Release activation method: Pull sleeve? Pull string? Lever and cable?
Weak link: String? Mechanical? pound break point
Crew: Driver? Spotter? Noseman? Logger? Photographer?

How many people typically read your issues of SKYTING?
How many people regularly skyte with you?
How many people do you know who have skyted?
*
*

[Tad Eareckson]

1983/07
*
SKYTING NO.15
JULY 1983
*
1983/07-01

PROFESSIONAL QUALITY EQUIPMENT NEEDED

by Donnell Hewett

The SKYTING Newsletter has now been published for more than a year, and during this time many pilots, and several hang glider businesses have begun applying its principles to meet their own respective needs. There is no doubt that improvements nave been made over the original skyting equipment used back in 1981. Yet as far as I know no one - and I mean absolutely no one except myself - is selling such equipment. To be honest, I am very surprised - and also disappointed. I was hoping that by now I would be able to purchase higher quality equipment than I, myself, could manufacture. In fact, I have deliberately put off designing better equipment because I felt that the equipment I had would be adequate until better quality components were available commercially. But such equipment has not been forthcoming and I cannot put off updating my equipment any longer. Some of the equipment that I sell is clearly becoming obsolete and yet it is still the best that is available anywhere at any price.

Since I have been grounded from further flying by my doctor at lease until this coming fall, I have decided to turn part of my attention toward equipment design. This issue fo SKYTING describes two new skyting bridle and a new tension guage, which I am willing to sell to those pilots willing to report to me their experiences using them. In my opinion neither of these items has been properly tested, but I believe they are both significant improvements over the old designs. My purpose in making these items available is not so much to go in the business of selling "unproven" towing equipment as it is to challenge others more qualified than I to get busy and improve the quality of available skyting components. So far, skyting has a good safety record, even using home made equipment. But with better equipment available, the future safety of skyting can only be improved.

Let me urge you, if you know of any type of skyting equipment which is commercially available, please - PLEASE - let me know what it is and where it can be found. I am not only interested in specialized skyting equipment, but also such things as professional skyting instructions and conventional towing equipment suitable for use in skyting (such as floats, releases, winches, reels, etc.)

I know that the other hang gliding publications are beginning to write towing articles and, with their larger circulation and higher prestige, they will eventually assume the responsibility of informing pilots about available skyting equipment (through advertising and articles). But right now there are a lot of people who are asking me where they can get equipment to begin skyting, and right now all I can answer is "Nowhere else but Kingsville, Texas!"
*
1983/07-02

LITERATURE REVIEW

Now that skyting is starting to gain a certain amount of acceptability within the established hang gliding community, articles on skyting and - can you believe this? - even other forms of towing, are becoming fairly common. Some of these articles contain information which may be of interest to you who subscribe to to SKYTING.

Since most of you probably already subscribe to the other hang gliding publications, (or can borrow a copy from your friends), there seems little point of trying to repeat everything mentioned in these articles. But one of the reasons for publishing this newsletter is to provide information. And since information about where to get more information is, itself, information, it seems prudent to include such information in this publication. Whew!

Therefore, I am going to briefly review some of the towing related articles which have recently appeared in Whole Air and Hang Gliding. These are the only two major hang gliding publications which I subscribe to, so if you run across similar articles in other publications, I would appreciate your sending me a copy of the article or else review the article yourself.

GEARING UP TO TOW by Tom Phillips and Donnell Hewett, Whole Air, March/April 1983. This article describes roughly the state-of-the-art in skyting development as of last spring. Included are photographs and drawing illustrating various skyting systems in use today.

TOWING 1983 We've Come a Long Way Baby, by Gary and Denise Whitman, Hang Gliding, May 1983. In this article the authors beiefly explain some principles behind skyting and then go on to describe their own towing system. Included in the article are photographs and drawing which illustrate such things as system stability (flying hands off, skyting a bucket, and crosswind takeoffs) and system components (bridle, attachment points, weak link, release, tension gauges, and take-up reel). Items not previously mentioned in SKYTING are (1) a garage door spring gauge with tension scale located at the front end of the vehicle, (2) a hydraulic tension gauge, and (3) an electrical driven take-up reel.

ROPE TRICKS by Tom Phillips, Hang Gliding, May 1983. This article describes Tom's first experience with skyting and includes another account of the accident described in SKYTING NO. 11 where Haward Haig broke his leg. The article emphasizes the importance of observing all, instead of some of the eight skyting criteria.

AIR-TO-AIR: Or, How to Turn Dreams Into Reality, by Tom Vayda, Hang Gliding, June 1983. This article describes the development of an air-to-air towing system used by the author to tow a Fledge IIb (or Fledge III) with a Foxbat trike. The system uses a reduction drive motor, a special towbar which goes around the propeller, and an attachment point at the nose plate of the Fledge. The author emphasizes the importance of using the exact same equipment, very experienced pilots on both ends, and good weather conditions in order to safely air tow his way. Photographs illustrate the article.
*
1983/07-03

THE CHALLENGE: Build a Better Bridle

by Donnell Hewett

As you well know, one of the major weaknesses of skyting is the lack of availability of professional quality equipment. Most of the skyters today use system components which were either home made from scratch or self-modified from conventional towing equipment. In order to help pilots get started skyting without running the risk of using improperly designed equipment, I have been running a small manufacturing business. It has been my policy to sell only the best equipment I can make to pilots who have read all the available material on skyting. In other words, I have tried to sell only the best I can make to the pilots who know how to use it.

But I am a university professor, not an equipment manufacturer. So there is no doubt in my mind that professional equipment manufacturers can produce a superior product to what I can make. To be honest, I am very disappointed they haven't done so. It is past time for second generation skyting equipment to be on the market. I have, therefore, decided to sell my own version of the state-of-the-art equipment and challenge the equipment manufactures to put me out of business by selling higher quality equipment for less.

THE ORIGINAL SKYTING BRIDLE

As you know, I have been selling copies of the original skyting bridle which I used way back in 1980. This bridle received much criticism. For example, the first Florida pilots to see it took one look and said, "No, thanks!" Others who were willing to try it reported severe problems and said they would never again tow with an unmodified skyting bridle. (See SKYTING NO. 8) In fact, there are more pilots today flying with modified bridles than with the original configuration because of the known weaknesses of the original bridle. Why, then have I continued to sell the original bridle? Precisely because its weaknesses are known! I know for a fact than when you use the bridle properly, it is very safe. It is also relatively ease to make and I can get the components locally.

But I have become convinced that the design is growing obsolete and should be replaced with one which is a little more forgiving of pilot error. I have, therefore, constructed a new bridle system which eliminates many of the weaknesses of the original bridle. I have freely taken ideas from various pilots who have been communicating through the SKYTING Newsletter as well as incorporating ideas of my own. This bridle is illustrated in Figure 1.

RELEASE ACTIVATION POINT

The original bridle was released by pulling on the sleeve of the body latch. The new bridle can be released by pulling on a string attached to the body release, the keel release, or the pilot's hand. The primary release point is the pull string in the pilot's hand. By properly adjusting the length of this string and the position of the ends of the control bar sleeve, the pilot can move his hand freely from down-tube to base tube while flying erect or prone. Yet all he has to do to release from tow is to pull the release line past the mid point of the control bar (he doesn't even have to turn loose of the base tube to do this.) He can also release by pulling his hand backwards (toward the tail of the glider), by shoving it forward (toward the nose), or by lifting it upward (toward the keel). If the pilot should stumble on takeoff (hands thrust forward) or fail to hook in (hands left behind the glider), all he has to do is turn loose of the control bar and the glider will be released from tow. In other words, the pilot does not have to be in control of the situation in order to release from tow (he does not even need to find his own tummy as in the old system), the system is designed to release when the pilot is in control and especially when he is not.

RELEASES

The heavy "horse bridle" releases on the original bridle have been replaced by "two-ring" releases. These releases are both lighter and smaller. This means they are less likely to tangle on the control bar and flying wires when released; less likely to hurt someone or something (such as the pilot's head, neck or shoulder; less likely to be damaged or cause damage when they hit the ground. They are also less complex and lighter. It should, therefore, be less likely to tangle with the equipment than the three-ring release. Of course, it does have the disadvantage of being harder to release under extreme tension, but because the weak link limits towline tension to reasonable values, the two-ring release should be more than adequate. (NOTE: For deep water starts, where no weak link is used, it would probably be wiser to use the three ring release than the two-ring release. But since I anticipate most skyting will be accomplished using a weak link (as skyting Criteria No. 7 requires) the two-ring release seemed the best way to go.)

AUTO-RELEASE LINES

The original skyting bridle had an auto-release line which automatically released the keel latch whenever the body latch was released by the pilot. The new bridle has two auto-release lines - one for each point of attachment. The bridle is designed so that if either release is activated, the other automatically releases as well.

At first we did not use the top auto-release line. We did like some other pilots have suggested - we used the pull release to release the top latch and then used an auto-release line on the bottom. But during one of our takeoffs, the bottom auto-release line snagged on some brush and released the bottom line. Without the top auto-release, the tow force was transferred to the glider and caused a nose-in. To prevent this from happening again we adopted the double auto-release mechanism.

In order for the top release to work properly when released automatically, we use the pin arrangement shown in Figure 2. The pin, itself, is a cotter pin bent so as to keep itself from accidentally falling out of the two-ring release. The manual pull line is tied to the end of the auto-release line and slipped into the cotter pin. To prevent the twine from slipping all the way down to the eye of the cotter pin (and, therefore, failing to slip back out later) a rubber band is wrapped around the neck of the cotter pin. When the pin is then attached to the two-ring release, a pull on either release line will trip the release. As the bridle falls away, the twine is pulled out of the cotter pin and everything separates cleanly. If the twing should somehow become tangled with the pin it will break, so there is no danger of an incomplete separation.

To "clean up the system" each auto-release line runs through the insides of the tubular webbing used to make the two-ring releases. By making this webbing extend beyond the flying wires and control bar, the probability of having the auto-release line and/or bridle line tangle with the glider, pilot, or each other is greatly reduced. (Remember how the old bridle can hang around the pilot's neck when released with the auto-release line on one side and the bridle line on the other side of the pilot's head?) Of course, the auto-release lines do have some slack at the slip ring end of the bridle in order to permit the bridle to adjust itself during flight without releasing prematurely.

The length of the auto-release lines determine the conditions under which they cause an automatic release. The top line is adjusted so that it becomes tight just before the glider "maxes out", the slip rings come together, or the top bridle line starts to hit the control bar base tube. The bottom line is adjusted so that it becomes tight just before the glider noses in during takeoff. In this way, the glider automatically releases whenever the glider tries to overfly the tow vehicle or the pilot noses in during takeoff. (See SKYTING No 6 for more information on adjusting the auto-release lines.) Remember, for proper operation the auto-release lines should be re-adjusted for every pilot-glider combination.

WEAR AND TEAR

The bridle is designed so that the pilot can easily replace the part that rubs on the slip rings. This prevents him from having to buy a new bridle every time the moving part wears out.

In order to prevent the bridle line from rubbing against the knots of the auto-release line and cutting them in two, the auto-release lines are tied to the bridle immediately below the bottom slip ring.

The only other parts of the bridle that should have to be replaced from time to time are the twine at the end of the auto-release line, the rubber bands on the release pins, and occasionally the release pins themselves (if they become bent or lost).

DISADANTAGES

From the above discussion, it looks like the new bridle solves almost all of the problems associated with the old, original bridle. But it does have its own disadvantages.

In the first place, some pilots prefer to release the top bridle before maxing out and fly only on the bottom bridle line. (This gets the top line out of the way of the pilot's head and upper body. It also reduces the probability of having the upper bridle line snag on the glider when the towline comes loose, the glider gets turned sideways, or the pilot over-flies the vehicle.) This is impossible to do when using the new bridle because it automatically releases whenever the top line is released.

The second disadvantage of the new bridle is that it has not been adequately tested. Since I have been grounded, I cannot test fly the bridle myself. And since no one else is currently skyting in the Kingsville area, I have very few opportunities to observe other pilots using the bridle. As mentioned last month, Carl Geers of Austin and Ann Hoehn of Graham came down last May. While they were here, they helped me evaluate the new bridle prototype. It was these tests that demonstrated the need for a double auto-release line and the need for a sleeve over the pull release line where it runs up the control bar. Because more tests are obviously needed, the new bridle is being sold only to pilots who agree to write me a letter giving their evaluation of the new bridle under flight conditions.

The third disadvantage of the new bridle is its price. Although the components of the bridle are relatively cheap, a lot of labor is involved in its construction. As a result, the price is set at $50.00 plus shipping. This is almost double the price of the old bridle, but I think it is a reasonable price for what I believe is the best skyting bridle available. If you know of a better bridle for less money, stop keeping the secret. Let's let the whole world know where better skyting equipment can be found.
+
Fig. 1. New Bridle System.

Hand Loop
Pull Release Line
Top Auto-release Line
Bottom Auto-release Line
+
Fig. 2. Top Double-Release Line System.

Top Bridle Line (acts as a sleeve)
Top Auto-release Line
Bottom Auto-release Line
Two-Ring Release
Top Auto-release Line
Release Pin
Twine
Rubber Band
Pull Release Line
Clamp
Sleeve
*
1983/07-04

THE HYDRAULIC TENSION GAUGE

by Donnell Hewett

The article by Garry and Denise Whitman in Hang Gliding, May 1983, rekindled my interest in obtaining a better tension gauge than that described in SKYTING NO. 4. Oh, the one I use is marginally adequate when I am driving, but my wife and some other drivers that have used it are very unimpressed, to say the least. There are even times when I, myself, have lost confidence in its reading. (For example, when the indicator line gets caught on something and fails to read properly.)

So after reading the Whitman's article, I again asked myself, "What is the ultimate tension gauge for skyting?" The answer came back, "Why an inexpensive electronic device which desplays digitally the exact towline tension right there in front of the driver's eyes!"

"Sure," I said, "and it will take me several months of work just to build on, too! So what is the next best - easy to build - tension gauge?" This time the answer was "Probably one like the Whitman's hydraulic gauge."

The idea was certainly worth a try, so I built one. Figure 1 illustrates how the design works. The towline tension pulls on the hydraulic cylinder causing a pressure which is read by the gauge at the other end of the hydraulic line. By using a cylinder of about 1 square inch, the pressure gauge reads the tension directly. And it can be placed anywhere the driver wants it, so that he can easily read it while driving the vehicle.

Although I have had only one opportunity to test the unit, (when Mike and Marsheila Haley of Lubbock dropped by Kingsville in July), I was very pleased with its performance at that time. There is no doubt that the design is vastly superior to the spring gauge system which I had been using. He had copied the Whitman's garage door spring gauge design. See Figure 2.)

The hydraulic tension gauge has several advantages over the spring gauge systems I have used in the past: (1) It is more reliable - responding rapidly to tension variations and returning consistantly to the correct setting. (2) It is more accurate. Although I have not made rigorous tests, I suspect that the gauge is accurate to within a few percent of the correct value if it has been properly calibrated for the true piston size. (3) It is more convenient - easy to install and easy to read. (4) It is compact - coiling up to fit a 1 ft circle. (5) It is portable - able to be switched from one type of vehicle to another in a matter of seconds. (6) It is rugged - able to read up to 300 pounds of tension and yet be undamaged should the weak link or towline break.

Of course, like everything else, it also has its disadvantages. The biggest disadvantages. The biggest disadvantage is that it is expensive. I don't see how I can afford to make and sell them for less than $150.00 each. :Yet this is still much cheaper than conventional towing equipment used to be (and still is). It's considerably less than the cost of a good low tension winch (even a non-powered one). It also beats leaving a $2000 hang glider lying around in the garage until you can affort to drive to the mountains unless you are lucky enough to live near them. And finally, it beats risking not only your glider but also your own skin when you try skyting with an inferior tension gauge.

I know in my own case that I would gladly - well, almost gladly - spend $150.00 to get such a gauge. In fact, I have already spent more than that getting myself this one.

If you want to buy one of these gauges, please remember the conditions: you must let me know your personal evaluation of the gauge after you have had a chance to use it. I need your input.

You should also be willing to give a few weeks to fill your order. I cannot affort to stock up on such expensive items, hoping that sooner or later someone is going to buy them. For all I know, tomorrow someone may come out with a better tension gauge for less money. I challenge you to do so.

By the way, if you already know of a better deal, please let me know so I can pass the information on to others and then go out of business.
+
Fig. 1. Hydraulic Tension Gauge. (Not to scale.)

HYDRAULIC CYLINDER
HYDRAULIC LINE
GAUGE
+
Fig. 2. Whitman Garage Door Spring Gauge. (Not to scale.)

HANG GLIDER RACK
TOWLINE
2" PVC PIPE
160 lb. GARAGE DOOR SPRING
INDICATOR
*
DEAR DONNELL
*
1983/07-05

ANXIOUS TO TRY SKYTING

Dear Donnell,

I think your materials are excellant. Your system is a milestone in hang gliding. I've had some experiences at conventional towing and I'm anxious to try your system. Hopefully, the tow will now be as much fun as the rest of the ride.

I will be towing over water using a winch. After I get comfortable, I will try land towing. I'll let you know the results.

I hope your arm heals quickly.

Harold Fields
Miami, FL
*
PREFER CONVENTIONAL TOW BRIDLE
*
1983/07-06

Dear Donnell,

A friend and myself, having over 200 tow starts (pop starts) each, have tried your system on our 165 Comets and find that we both yaw a lot. Not wanting to cut my sail to fasten a y-connection to my crosstube, I have decided to wait and see.

We now use the Emerson-Bailey tow system we used while boat towing - less the floats. On a mile long hard road we stretch out about 1200 ft of rope, attached to a scale and garage door spring as in Hang Gliding Magazine. After getting the slack out, a signal is given and the tow vehicle (a Jeep) starts. Holding back on the rope with the tension building to an overpowering pull, the pilot then runs about 3 or 4 steps and then becomes airborne.

The lockout possibility remains, but we both know what a lockout is and what it feels like when it starts - at a certain angle cross to a straight pull the pilot releases. A lockout is no problem provided you know what a lockout is and what to do about it.

A new pilot or a low time pilot should not be taught this way.

A Y-bridle is used, and when a stable, controlled start is seen, the top release is let go, allowing a top-out at approximately 1000 ft.

We will try your system again.

Tom Kellgore
Orlando, FL
*
1983/07-07

Dear Tom,

Thanks for the feedback. I will pass it on to others through the Skyting Newsletter.

You may be interested in learning that you are the first pilots who have reported having tried the skyting bridle and then prefered to return to the more conventional configuration. Naturally you must do what you feel is best for you, but let me remind you of some facts you probably already know:

(1) Failure to meet all of skyting's eight criteria (See SKYTING #3) results in a theoretically inferior tow system. Even approximating the criteria (attaching the bridle to the keel) is superior to a flagrant violation (attaching the bridle to the base tube).

(2) Dynamic tension control (which you seem to have adopted from skyting), is generally inferior to constant tension winch control. Yet most conventional towing pilots consider even the winch to be inadequate for safe land towing.

(3) Cross-wind takeoffs are extremely dangerous when using a conventional bridle. The forces tend to produce a ground loop even before a lockout has time to develop. And "road" towing almost always guarantees cross-wind takeoff attempts, because the wind is almost never down the roadway.

(4) Lockouts on takeoffs are more probable when land towing than when water towing because wind gusts are stronger and wind gradients are greater over land than over water.

(5) Any lockout on takeoff over land is extremely dangerous. Even when the pilot recognizes the phenomenon and releases immediately, there is insufficient altitude to turn back into the wind before landing. A down-wind landing or a cross-wind ground loop is almost guaranteed, and the solid ground is very unforgiving in these cases.

In short: WHAT YOU ARE DOING NOW IS CONSIDERABLY MORE DANGEROUS THAN WHAT YOU WERE DOING PREVIOUSLY! Please realize this and proceed carefully. I'm sure you will.

Since you said that you plan to try the skyting bridle again, let me make a few suggestions for next time:

(1) Don't try so hard to make a short takeoff. I know you are familiar with "pop starts" and do not want to increase the chances of a poor takeoff by making a long run. Furthermore, you are wise to try to stay with what you know. But skyting is more like conventional foot launching, where you begin by gently running off a hill, not by jumping off a cliff. After you master the gentle takeoff you can perfect your short takeoff technique.

(2) Keep the towline tension low, don't drive too fast, and don't climb too fast. In short, drop everything down from what you are used to. (But not so far as to cause a stall.) With your Comet, you should start with a towline tension of about 50 to 75 pounds, with an air speed of about 22 mph, and with a climb rate below 200 fpm. Under these conditions your towed flight should closely approximate the conditions of free flight and you should have less of a yaw problem and less tendency to over-control. As you gain more experience using the skyting bridle, you can increase these values to whatever you feel are proper.

In short: BACK OFF FROM THE FLYING YOU ARE USED TO, AND PRETEND THAT YOU ARE MORE OF A BEGINNER, STARTING ALL OVER. Other pilots have learned to fly the Comet comfortably while towing with a skyting bridle, I'm sure that you, too, can do so. Of course, it is possible that you may still prefer to fly with the conventional bridle even after you gain more experience on the skyting bridle. If so, please let me know, as it is important to know such things.

Donnell Hewett
*
*

[Tad Eareckson]

1983/08
*
SKYTING NO.16
AUGUST 1983
*
1983/08-01

THE FIRST SKYTING EXPERIENCES IN MEXICO

by Gary Gower

Everything began with the May/83 Hang Gliding Magazine article, Towing 1983, by Gary and Denise Whitman.

Here in our area we have some big dry lakes, but the access to the mountains in the prevailing wind side is almost impossible - about 1 mile climbing a 45 degree slope with plenty of vegetation. We spend all morning just to get to the take-off. In compensation we catch super thermals of +700 fpm with great X-Country potential all over the lakes (more than 50 miles long).

Our impossible dream was to tow to the top of the mountain.

When I read the article, I immediately phoned Jorge Lopez and Alejandro Chavez. We studied the article thoroughly, got convinced, and began to look for the equipment. I even designed our release. Everything else was as the article mentioned.

So Sunday, 17 of July, we went to the lake. This time of the year is the raining season, so the ground outside the road is very muddy and slippery. The clouds were low and 100% cover. We had a 8-10 wind about 10 degrees from the right, no turbulence at all. Conditions looked good for the test flight of the skyting system. We had a 1,500 ft rope (1/4" polypro).

I was going to be the test pilot. Never-the-less, the three of us are rated "Avanzado" in the Asosiacion Mexicana de Vuelo Libre (USHGA Hang IV equivalent). We had no experience in towing. So, what if the system won't work with our gliders? We are flying La Mouette "Atlas" gliders and the article mentioned a "Harrier". The 16" distance from the glider's C.G. will be O.K. for all gliders?

I imagined the feeling of the SKYTING pioneers when they made their first experiments. Would I fly or crash?

We decided to test it first with a 30 ft long rope with Jorge and Alejandro pulling me as a kite. It was Wonderful!! Totally stable and self-corrected automatically. I got a lot of confidence and got ready for the test flight. Jorge was on the tow vehicle, I was in the glider, and Alejandro was near me with the walkie talkie C.B.

"How hard is the initial pull?" asked Jorge through the radio. Nobody knew, and the article didn't specify clearly how quickly.

We had this safety facts:

1. For this flight we were using a weak link of about 100 - 120 pound breaking point so he couldn't pull too hard without breaking it.

2. Just before, I got airborne easily with only the two of them pulling by hand.

3. Jorge will accelerate only up to mark No. 4 in the dial.

So in conclusion, he will initiate slowly If I need more speed Alejandro could tell him through the radio.

He signaled Ready ... GO!

The rope pulled and I began to walk then run, no take off! I shouted faster, faster ... Faster!!! Also Alex through the C.B.

As the prevailing wind was slightly from the right, I was automatically crabbing left in the direction of the mud bushes and a fence about 50 ft away. I was running as a foot-ball player toward a touch-down, but with giant steps. Alex shouted the last FASTER!! and just one step before leaving the road, I was airborne. The glider was lifting fast enough - 350 fpm. Jorge, as we decided, reached the speed we needed for the No. 4 mark in the dial. When I was about 250 ft AGL the weak link broke. I released the 100 foot rope that was left (my release also worked) and made a perfect glide to a perfect landing. INCREDIBLE - the first flight to a dream come true for all of us - Safe Towing.

We as members of the ASOSIACION MEXICANA DE VUELO LIBRE, A.C. (Mexican Hang Gliding Assn.) sincerely congratulate Donnell Hewett for his invention and to Gary and Denise Whitman and Larry Coonrod for the great article and photos.
*
DEAR DONNELL
*
GUIDELINES FOR SAFE TOWING
*
1983/08-02

Dear Donnell,

The Swedish national hang gliding association has decided to look closer at the latest development in towed takeoffs. Only a few months ago we still talked about towing with horror.

As the Swedish representative at the towing seminar in Waldeck, West Germany I had the opportunity to witness many successful ones. It is my task to submit a set of tentative rules and recommendations for the board shortly. Although the Skyting (or similar) system was demonstrated, no written material was available. In the May issue of "Hang Gliding" two articles refer to your "Skyting" guidelines. Sweden, lacking any modern towing experience, would greatly benefit from the information you could provide.

Bjorn Montgomerie
Ekero, Sweden
*
1983/08-03

Dear Bjorn,

I wish it were possible to maintain better communication with you European flyers because there is no doubt that we are discovering many of he same problems. It was not clear from your letter what kind of towing system was being used (particularly concerning the unsuccessful launches). In fact, I know almost nothing about what type of towing you are doing there, and would appreciate whatever information you could send me.

The information I am sending you should bring you up to date on what is happening here. I hope it helps you in your search for guidelines. My own basic guidelines for safe towing systems are the eight "Skyting Criteria" described in SKYTING NO. 3. As far as more detailed rules are concerned, I believe it is too son to become very specific. As you can see, there are so many different ways to apply the principles of skyting to various types of towing situations that to establish rules favoring one or the other is almost certain to be detrimental to the long term safety of towing. Good luck on your assignment.

Donnell
*
1983/08-04

PNEUMATIC TENSION GAUGE AVAILABLE

Dear Donnell,

I just got your SKYTING #15 today. This has caused me to get into this a little sooner than I expected.

We have been skyting for 2 months. We use a bridle like yours, except that we have a release at the apex of the bridle. We use 100 ft of 1/4 poly leader, a streamer to find the leader in case it was dropped in a bean field. We use a weak link of twisted line that will break at 200 lbs. Next, 1000 ft of 1/3 poly line. This hooks to a cylinder. This cylinder is just as important as your bridle.

This cylinder took me some time to perfect. My cylinder has 7" travel with 1 1/4 " bore. My cylinder doesn't leak down or gain any pressure. I have tested it to three hours with no loss or gain in pressure. This reads into a gauge that is calibrated to read exact pressure.

I have seen your diagram and Gary Whitman's on this cylinder. It is not as easy as you describe. I will sell this assembly to anyone interested and your price of $150.00 sounds reasonable.

Anyone interested should give me enough time to get together the new cylinder. I expect in two weeks. I would also be glad to sell the 1/8 " poly line and the 5/32 " poly. This will be used with a longer road.

By the way, my cylinder doesn't have oil in it. It uses air pressure. The oil will hydralock. This creats too sound a feel and a lot of gauge movement.

Butch Pritchett
Box 299
Finley, Tenn. 38030
(901) 285-9490
*
1983/08-05

HONDURAS INTEREST IN SKYTING

Please send me all the information that you can about the special system for towing that you designed. Especially the price, because I am interested in it and I want to do it in the beach towing with a boat.

Gustavo Erazo
Birdman Clubs President
San Pedro Sula, Honduras
*
1983/08-06

TIRED OF CHASING HILLS

Dear Donnell

I have read with great interest your article on "Skyting" in the may 1983 edition of "Hang Gliding".

Like all good ideas, they should be simple so as there is less to go wrong. Your ideas are just that - simple and effective. Congratulations. You have obviously put a lot of thought into the ideas.

I must be like you - tired of chasing hills but I have always been wary of normal towing mehtods.

Anyway, Donnell, I would like to know all I can about your system, so could you please let me know about the cost of your publications etc. on towing correctly.

Frank Smallman
Glen Innes, N.S.W.
Australia
*
1983/08-07

MEXICO HONORS DONNELL HEWETT
*
1983/08-08

Dear Donnell,

We appreciate very much the Skyting documentation you sent us. We are sending you enclosed with this letter my contribution about our first experience with the SKYTING SYSTEM.

We are also giving you an "HONORIFIC MEMBERSHIP" in our ASOCIACION MEXICANA DE VUELO LIBRE, A. C. as a recognition of your effort in the Hang Gliding Sport. You will receive a Copy of our Newsletter (translated in my best English), all the help we can give you with the development of the Skyting System, and also all the help you may need when you decide to fly in our Mexican sites.

Gary Gower, President
Asoc. Mex. de Vuelo Libre
Guad., Jal., Mexico
*
1983/08-09

Dear Gary,

Thank you very much for the "Honorific Membership" in your Asociacion Mexicana de Vuelo Libre, it is the nicest award I have ever received for my Hang Gliding efforts.

Donnell
*
1983/08-10

WATER TOWING EXPERIENCES

Dear Donnell,

Just a short letter to let you know how things are going in northern Minnesota.

Terry and I met Gene Stone at Lake Pokegama (Po keg' a ma) to do some long rope (3150' winch (reel really) skyting last month. With five miles of open water ahead of us, we had a steady fifteen mph wind in our faces. The winch (High Perspective of Canada) was set to reel off at 150 lbs. The weak link, between the 150 ft 3/8 inch poly leader and the 1/4 inch 3,000 ft towline, was 220 lb breaking strength. A six inch diameter styrofoam float kept your original (horse release) skyting bridle from sinking. The float was fastened to the leader rope one foot ahead of the bridle. Our 14 ft tri hull boat with 85 hp Johnson is slow to get on plane so Gene held the winch in the free wheel position until Terry got the wind meter on the boat to read between 20 and 25 mph. When it looked like about 140 ft to 500 ft had been reeled out, I shook the sail to signal Gene to release the handle and let the winch go into its pretensioned mode of 150 lbs. The 400 ft of rope allowed enough stretch to keep the starting inertia of the reel from breaking the weak link.

Three steps and I was off the beach. The highest flight of the day was 2,450'. The longest was fifteen minutes. We used about one mile of lake to tow up as the wind aloft was about 22-25 mph.

A week or two later we did deep water starts into a 8 mph wind. We started with 140 ft of our 150 ft long 3/8 " poly leader rope reeled off the winch. The weak link was still about ten feet short of being reeled off.

When the kite left the water we released the brake on the winch and let it go to its pre-tensioned mode for the ascent. We were on a shorter lake and only were able to get to 1,500 ft above the surface. The boat wouldn't pull the kite out of the water in "no wind conditions" and the free wheeling and pop technique breaks the weak link. So we haven't figured out how to get airborne in "no wind conditions" with our boating rig.

Deep water takeoff with the Skyting bridle feels completely opposite the technique used for deep water takeoff with the conventional tow system.

With the conventional system, a yaw while taxiing and before flying speed was reached, was corrected by pulling your body slightly to the same side as the leading wing and holding back on the leading of side of the base tube.

With the skyting system a yaw while still in the water taxiing and before flying speed is reached, is corrected by moving your body in the direction of the trailing wing and pushing on the trailing side down tube. By the way, this little trick might even help correct adverse yaw in the air for people with the newer double surface gliders. Next time your glider yaws left, and you are not near stall speed, move slightly to the left and push out with your left hand a little. Hey, Donnell! I think I may have just stumbled onto something here, concerning adverse yaw under skyting tow.

It would seem to me that if a pilot was pushing out on the bar and pulled him/herself on one side, the glider would have to yaw more adversely than if they moved to one side and did not push out. Well, I'll leave that for you to ponder and get back to the water handling.

To get out of the water with the skyting system, I have found that I have to push out all the way on the down tubes to offset the resistance the floats on the "A" frame get while moving against the water. After my belly and glider are planing on the surface, I let the bar back to stay on the surface until there is more than enough speed to leave the water.

This short letter is getting out of hand, so I'll close after a few water handling tips. This tip is about wing tips. After you land right side up the in the water, and the wind is drifting you backwards, keep the wing tips from going under water. Otherwise you will roll the glider up-side-down so only the floats will be showing. Then you better have a fast easy way to get unhooked. If you are using a prone harness, it will hold your head about one foot under the surface, making it real tough to laugh.

If while drifting backwards (right-side-up now) and the wind should raise your left wing, move your body in the direction of the low or submerging right wing tip - - Yes, you read that correctly and I didn't make a mistake. If you move toward the high wing while drifting backwards, you'll find that there is really no faster way to put the glider up-side-down in the water. Move toward the low right wing. This puts more of the glider to the left of your body and since the glider to the left of your body wants to move down wind faster than your dragging body will allow, it will pivot around you putting the low wing up wind which, of course, will raise it. This assumes that you have reacted in time. Otherwise, abandon ship.

More tips next letter.

Bill and Terry Cummings
Hoyt Lakes, MN
*
WEAK LINK PROBLEMS
*
1983/08-11

Dear Donnell,

Enclosed are two sample lines, are they similar to what you use for weak links?

A is Uraline Products Husky Twine braided nylon 177 lb test. My test is to gradually hang my weight on single string while standing on scale - I weigh 125 - when line breaks scale reads 25. Don't know what a loop breaks at.

B is braided nylon #18 line 180 lb test. My tests: it holds 125 lbs.

Using your bridle configuration, a Yarnall release, and 2-way radios (until we get tension gauge) I've towed on each A and B lines.

The A line would break at 5-10 ft altitude. For a couple of days I couldn't understand why I couldn't tow on 100 lb line. My glider (UP 178 Condor) flys 6:1. At 180 lb total weight that's 30 lb drag. Adding enough excess thrust to climb out at 8 ft/sec (480 fpm) works out to

(T-D)=
RcW/Vc=
8/180/40=
36 lb.

30 + 36 = 66 total pounds, so why was the line breaking at 100 pounds?

I was neglecting the fact that the flight path would be tilted up 8/40, 1:5. My 180 lb lift force gets tilted aft enough to add another 36 lbs for tow to overcome. So I'm up to 30 + 36 + 36 = 102 lbs. No wonder a line is breaking!

Towed on B line to about 100'. Broke it next day. Using loop of B line for weak link, I switched to 1/8 inch poly braid line. Towed to about 150 ft at which point my surgical rubber tow line untied. (When I get a parachute shroud line I'll eliminate the rubber line.)

I'd be interested in any additional information similar to Bill and Terry Cumming's ((Cummings)) (Skyting 11) on tayloring weak link breaking strength by choice of cord and knots. Right now I'm going to proceed with a loop of A line and a square knot.

Jerry Martin
Dayton, OH
*
1983/08-12

Dear Jerry,

Your method of testing seems accurate enough except you should test the same configuration you will be flying with. If you are flying with a single strand, I am not surprised your weak link breaks too often. You should be towing at 50 to 75 pounds, and a 100 to 125 pound break point simply does not give enough leeway for tension variations - particularly without a tension regulator. If you are flying with a loop, you should test a loop tied with the same knot. Otherwise you don't know what is happening.

It has been our experience that a weak link that breaks at one "g" of force is about right. For a 180 pound total weight (glider and pilot and instruments and equipment on board) your weak link should break at about 180 lbs. Twenty pounds either way should make little difference.

Donnell
*
SOME QUESTIONS AND ANSWERS
*
1983/08-13

Dear Donnell,

I have always wanted to tow but felt too much danger was involved. Your skyting system seems to be the way to go. Since I am from the flatlands in Minnesota, but here in Wyoming because of the big hills, I have followed towing info. for years.

I am moving back to flat MN in mid August and would like to be towing by then. MN is nothing but cloud streets in the fall, and would like to go for the big X-C flight (200).

I am a high air time pilot, 300 hrs in last year, but a very cautious pilot. Have flown since 1974.

What do I need to know to keep me alive while towing? I have a friend back in MN that will start towing with me also, so we will take turns driving/flying.

All the info. I can get will be greatly appreciated. I fly a Comet II, my friend flys a Raven 209, have you towed either? Also, is it wise to tow up in mid day boomers?

We plan to tow behind a car with garage door spring etc. as in Hang Gliding May 1983 issue.

Paul Lundquist
Sheridan, Wyoming
*
1983/08-14

Dear Paul,

You asked what you need to know to "keep me alive while towing". I recommend that you read the enclosed material very carefully and proceed with caution.

Now in reference to your specific questions: No, I have not flown a Comet II. I have been the driver for pilots flying both the Comet and the Raven 209. Both of these gliders have an adverse yaw tendency when skyting. Read the material which discusses this problem. In short it says, "Resist the tendency to over-control the glider and you can learn to skyte these gliders with confidence and control."

Once you have become familiar with the flying characteristics of your glider while skyting, there is no problem towing up in mid day boomers. Control on tow is only slightly more difficult than free-flight - and we are working to make it as easy to control the glider on tow as in free flight.

Donnell
*
DEAD WEIGHT DAMAGES GLIDER
*
1983/08-15

Dear Donnell,

We are very encouraged by everything we have read so far about this system and after reading Gary Whitman's article in Hang Gliding decided to go for it. A friend of mine who is a very experienced pilot and myself have designed a system that is very similar to the one Gary described. We are using a spring scale, 2000 ft of 1/4 " polypro, 1000 ft of 1/8 " polypro, a 170 lb weak link, and a three ring release, in addition to the center of mass bridle system.

We haven't tried out our system yet but that will come very soon. We did however try a dummy flight using 150 lbs of sand in a flight bag and an Electra Flyer Trainer as the glider. We had some interesting results. Winds were calm (it was 6:30 in the morning), and with me holding the keel, the truck accelerated to about 25 mph. The takeoff was as smooth as glass. The glider rose to about 25 ft, at which point it initiated a slightly banked turn to the right. After a few seconds it began to recover, but then banked again in the same direction and continued on out until it was about 45 degrees to the road. At this point the driver slowed and the glider hit the ground fairly hard - enough to bend both downtubes. We didn't try it again, it's hard to find replacement parts for this old glider.

We are not sure what caused the turn and why the glider didn't recover. We don't blame the system - at no time did the turn resemble a lockout and the bank angle never exceeded 15 degrees. We feel that the glider itself may have been slightly out of trim. When we set up this test we used several loosely attached bungie cords between the flight bag and the control bar to minimize what oscillations we thought might occur. It's possible that this tension, though slight, may have interferred with the proper operation of the system.

Never having towed before, we both have some apprehensions and wish there were someone near us using this system. If you know of anyone, please let us know. We could use some first hand advice. I believe our system is as safe as we can make it and are following all eight of the Skyting Criteria you have outlined. I hope we can advance far enough to catch a few of these booming desert thermals before the summer is over. Thanks.

Scott MacKnight
Price, Utah
*
1983/08-16

Dear Scott,

Thanks for writing and sharing your experiences with us. I am sorry you damaged your glider. I personally have never towed a "dead weight", so your evaluation of the cause is just as good or better than mine. You might contact Gary Whitman if you want to persue this issue further. I am sure your glider would have to be in perfect trim to tow the way you tried. Ask yourself what would have happened if you launched the bag of sand from a hill side. I suspect, the same thing.

Less you get (or already have) the mistaken impression that the skyting bridle stabalizes a towed glider, let me remind you that the object of skyting is to mimic free flight, not stabalize towing. In practice, it does a fair job of this - but not perfect (note the adverse yaw problem). Remember, too, that the pilots with conventional towing experience have more difficulty adapting to the characteristics of the skyting system than experienced hang glider pilots with no previous towing experience. In other words, you should have less trouble than conventional tow pilots.

No one else in Utah is currently subscribing to the Skyting Newsletter, so I cannot give you the addresses of such a person close to you. Let me, therefore, briefly outline my own suggestion as to how t proceed.

(1) Do your homework. (You have apparently all ready done this.)

(2) Get a complete skyting system. (You have apparently also done this.)

(3) Pick a day with a gentle breeze (about 8 mph) coming straight down your runway (clear of obstructions). Begin with about 500 ft of elastic towline (parachute shroudline is recommended but 1/8 " nylon or 1/8 " polypro will work).

(4) Begin with your best pilot, towline through the control bar, and with training wheels. Tow to about 50 or 75 ft on the first flight, climbing gradually (25 mph air speed, less than 200 fpm climb, and about 60 pounds of pull).

(5) After the first flight, you may want to put the bottom bridle line under the base tube. This will give you a better climb rate. On this flight, climb to 400 ft or so.

Of course, if your pilot is inexperienced at flying a hang glider, you should begin with the outline in SKYTING NO. 1 and follow the gradual advancement plan. Also, if you want to persue every precaution, you may want to begin towing over water.

Let me know how things turn out.

Donnell
*
SOME SUGGESTIONS
*
1983/08-17

Dear Donnell,

I have a few comments and suggestions as follows:

March/April 1983 Whole Air p. 34. "Skyting as coined by Donnell Hewett refers to a complete system for towing, the term in commonly being applied to the bridle itself." To differentiate between the Skyting tow system based on the Skyting bridle and other systems, I would suggest, "Skyting Tow Systems" the safer way to tow.

On newsletter time and effort, how about bi-monthly or a quarterly? Same number of issues per subscription price but over a longer time period.

The Skyting back issues often mentioned in Skyting articles could possibly have the technical information collected into a Basic Skyting Handbook.

P. 5 June 1983 Skyting, a note for Mike Haley: The word supine has negative semanic connotations - recumbent or reclining would be better, i.e. as Websters New Twentieth Century Dictionary unabridged Second Edition reads "sluggish listless passive," as describing supine and that doesn't sound like interesting flight style.

SKYTING SEMANTICS

Recumbent, recline
both very fine,
But because of semantics
please leave out supine.

Mike's skyting Lubbock system is most likely a safer way to fly than prone; hopefully he can use more positive skyting semantics.

Edwin G. Sward
Worcester, Mass
*
1983/08-18

Dear Edwin,

You suggest that I differentiate between a Skyting Tow System and a Skyting Bridle. I do make that distinction, but I cannot control how others use the terms.

Now concerning the bi-monthly or quarterly newsletter. I am a creature of habit. By putting the Newsletter out every month, I get myself in the habit and this makes it easier. If I only put it out every tow or three months, I would tend to put it off and not get it done.

The reason I have not written a Basic Skyting Handbook is that, in my opinion, skyting is not yet ready for such a book. There are certain questions I feel should be answered before a book should be written. For example, does the crossbar attachment point really solve the adverse yaw problem?

Finally, in reference to the use of the word "supine", remember, Mike Haley is not the only pilot who uses this term - it is used almost universally among hang glider pilots to describe flying in the "recumbent or reclining" position.

Donnell
*
AIR TOWING EXPERIENCES
*
1983/08-19

Dear Donnell,

Congratulations! I'm pleased to see that you and your bridle system are finally getting some attention from the 'boys out west'. It is recognition well deserved and somewhat overdue in my opinion.

It has been better than a year since my visit to Kingsville and the resulting introduction to hang gliding South Texas style. I'm not well known for my punctual correspondence, however I do try to keep promises . . . so I owe you this note which follows.

Four air tow flights were recently accomplished here in San Antonio which utilized your bridle and tow-line system. My Pterodactyl Ascender was utilized to tow my friend Marten and his Harrier 177. All my flights were successful although the 'Dactyl' and the speed range of the two ships was not really compatable. Opportunity permitting, we intend to trade pilot positions and pull my Comet 135 which should help the situation considerably.

Technique used was basically as outlined in SKYTING #4 with one exception. To reduce the drag created by having the pilot chute in the tow line at the weak link, the apex of the chute was attached by a rubber band to the weak link itself. Therefore, the chute does not inflate unless the weak link separates.

The following problems were encountered:

(1) Failure of the glider to maintain proper tow position. the person being towed can actually determine the attitude and flight path of the tug. A tow release on the tug is essential.

(2) Failure to properly match the speed capabilities of the glider and the tug. We were aware of this problem from the beginning. In our situation the result was that the fixed tips on the glider constantly tried to raise its nose while the Pterodactyl was forced to operate below optimum climb speeds.

The first tow was aborted after takeoff because of glider position relative to the tug, i.e. much too high. The next three attempts were without incident and resulted in tows to 2500 feet above the ground. Average rate of climb was 300 feet per minute. A few more horses or a little less drag would be nice.

That's the scoop! I'll keep you informed of further events. Best wishes to all down south.

J. T. Collins
San Antonio, TX
*
1983/08-20

Dear J. T.,

Thanks for writing. I appreciate you sharing your ultralight towing experiences. Information on ultralight towing is really hard to get. I am sure people are doing it, but few are reporting it. I hope you have had a chance to read the article AIR-TO-AIR by Tom Vayda in Hang Gliding, June 1983. He points out several things that could possibly be of use to you.

I like your idea of using a rubber band to keep the parachute collapsed until a weak link breaks. The two problems you mentioned (glider effecting ultralight and incompatable speeds) were to be expected. I hope you can solve them to your own satisfaction. Keep us informed.

Donnell
*
1983/08-21

NEW ZEALAND INTERESTED IN SKYTING

Dear Donnell,

After reading several articles about towing, I've decided to get back into it again. We used to do towing here several years ago - the old way with towing frames - but after several near mishaps we decided to give it up until now.

I got your name and address from the May issue of Hang Gliding. What I would like from you is a very detailed explanation of how to set up the system to a glider/harness with any other relative information. The type of glider that I'm presently flying is a Moyes Missle.

Please explain to me as if I am a simpleton (thick) because I haven't anyone to cross reference or ask.

Dave McGill
Blenheim, New Zeland
*
1983/08-22

AUSTRALIA WANTS MORE SKYTING INFO

Dear Donnell,

Thank you very much for SKYTING NO. 1, please send to No. 14 Skyting. I would appreciate all haste due to a future house moving plans in 2 months.

Looking forward to much reading and possibility of visit to Texas in the not too distant future.

My appetite is ravenous for the long awaited flat field flying that will eventually bust open this closed circuit sport, for more than the patient privileged few to enjoy.

Here's to thousands in the air.

Tony Webb
Newport Sydney NSW
Australia
*
*

[Tad Eareckson]

1983/09
*
SKYTING NO.17
SEPTEMBER 1983
*
1983/09-01

TOWING - A NEW ERA

by Denis Cummings
16 Rawcliffe St.
Singleton, N.S.W.
Australia 2330

I never thought I would be towed in a hang glider. Even though the history of hang gliding in Australia has its roots deep in the "flat-kite" waterski towing era of Moyes, Bennett, Duncan, etc., I have always had a bloody good argument for not being towed: - a) Lockout - it has killed far too often, b) Pilot not in control - his life totally in the hands, eyes and reflexes of two people - observer and driver, c) Full tension release/rope failure - that "loop the loop" possibility. Thus, for me, the old towing system seemed unacceptably risky in smooth wind conditions and suicidal in turbulent conditions.

The thought of inland towing - where the thermals are - has been maddening. If only it could be done SAFELY.

By the time I received my May 1983 copy of "Hang Gliding", I had dismissed the "constant tension winch" idea together with the "tow off the body - not the A-frams" idea (after the discussions for and against in Skysailor some time back). One article, "Towing 1983" by Garry & Denise Whitman, stirred me. It describes a car-pulled, fixed rope, low tension towing system. The bridle attaches to the glider keel about 400 mm in front of the hang point, and through the rings (or pulleys) onto the chest area of the pilots harness and onto the towing rope. It is always balanced so that 1/3 of the tow load is on the glider and 2/3 is on the pilot. With 2/3 the tow load onto the pilot, the pilot tends to follow the direction of tow, which in turn produces a load included billow shift correction to the glider, making it follow the direction of tow also, thus being directionally self-correcting or stable. Other features are: a) low tow tension (no "loop the loop" high tension release failures) b) no observer needed (in fact observes are discouraged) c) weak link insurance - fails if driver makes an error and lets tow tension exceed safe limit and d) supposed to be safe in crosswind (thermally) turbulent conditions.

Was this it? Many discussions (and beers) later, I was more convinced than ever that the system was correct in theory and was worth a try. With promises of shared expenses ("as long as you get everything for nix.") from Bill Poole and Mollo, I started scouring the dumps for old hydraulic rams and cable drums. I was, however, permitted to find out the cost of new tow rope. My hurried search for Kevlar of the suggested size was pretty disappointing as was the inability of the rope manufacturers to give me any accurate details of rope types, strengths elasticity, etc.. The metric sizes in Australia were also different to the imperial sizes available in America.

After an early-morning phone call or two to Garry Whitman in America, it was decided to drop the kevlar idea for ski rope. The cost would probably have made this decision for us at a later stage anyhow. As polypropylene ("polypro" in article) was not readily available in the sizes needed, it was decided to use 900 m (3,000 ft) of 4 mm. diameter hollow plaited polyethylene (ski-rope). This would give approximately the same stretch as the rope combination in Garry's article. This was ordered, together, with a roll of 6 mm ski rope for the 100 ft leader and for bridle anchors on kites and harnesses. The total cost was about $140.00.

Not liking Garry's garage door spring system, I set out to get a hydraulic tension measuring system. As hydraulic cylinders, with compression chambers on the piston rod side were found to be expensive, I finally chose a single action master brake cylinder from an old truck. The towing line tension had to be converted to a compression on the hydraulic ram, and this was easily achieved by a 1:1 lever arm. A pressure line and gauge were attached, and a hinged mount for my car's tow-bar was added. Total cost was about $50.00, including some engineering work.

The bridle was simple, with all parts coming from the local water-sports shop. The only doubtful bit was the release. After much testing on the ground, it was shown that the available spinaker boom release carabiners were only useable if set up on the bridle in exactly the correct manner. (A major worry prior to trying the system, this proved to be easily corrected in flight if any misalignment caused the release to not open. Out of 115 launches, it only happened twice, and release by hand was possible after hauling in the bridle.)

With the rope delivered, the tension cylinder calibrated and a weak link of about 150 lbs tested, it was time to try out the beast. The rewind drum/storage winch would have to wait. A few hurried phone calls to the sailplane club at Warkworth, and permission was obtained to use their airstrip for testing.

Funny how all your hang gliding mates desert you when you need them!! At last, with the help of a local pre-Hang I pilot, who had never seen towing before, it was possible to launch my Magic II with 2 used car tyres instead of me! That's showing supreme confidence - rather damage the kite than me! The M II rose and proceeded to follow the car up the strip on the end of the 150 ft of rope. When I lost sight of it in the rear view mirrors, I slowed the car to let it descend. As I stopped the car, the kite started to overtake its rope, tipped slightly right, and did a 2-point landing (a-frame & nose).

So far so good. No pilot input needed to keep it on track. Now I laid out 1000 ft (300 metres) of rope plus 100 ft (30 m) of leader, clamped on radio and vario, instructed a very nervous driver to "drive until the gauge shows X, or I give you other instructions by radio", and got into the harness. With only 1 or 2 m.p.h. of headwind and no wheels, I thought I would have to run like hell to get it off. "Go" to the driver- as slight tension comes on the rope I start running - I quickly overtake the rope, drop and slew the kite sideways - with the kite on the ground, the weak link breaks.

Me: "You drove too bloody slowly - I passed the rope".
John (driver); "I didn't want to accelerate you too quickly".
I'd given up smoking a week earlier - "John, gimme a smoke".

The morning westerly then died completely and the s/easterly started, so it was then necessary to shift to the other end of the strip. We did this with the M II on the back of John's ute, at the same time the sailplanes were changing their winch system and planes around.

The 3-5 m.p.h., 30 degree off, headwind that greeted us when we were ready at least gave me a breeze in my face as I picked up the kite. "Go" to the driver - let the kite pull me forward as I start to run - kite lifting its own weight - now takes up my weight - Oops! base bar sinking slowly to ground - "Faster" to driver - too late - bar hits, kite noses in, weak link breaks - no damage except to ego as sailplane pilots shake their heads.

Me: "You got it going O.K., but didn't keep accelerating."
John: "It went to X O.K., so I didn't speed up."
Me: "Well - next time take it to X plus."

This time, all goes well. The glider takes my weight well and I rise 50-100 ft before the leader comes snaking back to me - bloody weak link has broken.

Me: "How much bloody tension did you pull on then?"
John: "I only went to X plus, then I concentrated on driving."
Me: "If it goes over Y, you break the weak link."

Next time, being lazy, I lay back prior to take-off and the weak link breaks as I am about to run. My fault- don't hold back. Once again, this time I climb steadily to 200 ft before the line breaks, and I fly back to my takeoff point. By now its clear that the weak link is too weak for a 190 lb pilot plus 185 sq. ft. glider, so a stronger weak link is used.

Now I slowly climb to 300 ft before releasing. The climb rate has only been about 200 ft/min (should be about 500) but John has noted the gauge reading. For the final trial, I launch - talk John "faster" until the vario gives me 500 ft/min - tell John to note the new gauge reading - slow car and release - a good 400 feet. Ego returns as I get a standing ovation from the sailplane pilots after I complete the landing circuit and float onto my takeoff spot.

By now some of my "so-called friends" arrive after having an uninteresting day upsetting the local farmers at Glennies Creek. One more tow, this time with 2000 ft of rope for a climb of 500 ft, to show them how easy it is and a final landing in the front yard of the clubhouse. At this stage I'm sold, John's recovering from nervous exhaustion, and the sailplane pilots are relieved. There's a thoughtful sparkle in the eyes of some of my "so-called" friends.

Bill Poole (who hates the sight of blood and had thoughtfully stayed well away all day) got an enthusiastic earbashing on my return home.

As Warkworth Airstrip was not useable during the week (commuter airlines), the search was on for any good paddacks/old airstrips. By the following Friday, we were ready to go on a 1.1 km ex W.W. II strip at Jerrys Plains. With Bill instructed how to drive, I had a couple of flights to 800 ft. Now it was a nervous Bill's turn, with me driving for the first time. Slight disbelief after the first flight - full on enthusiam after the second.

- "Only took 2 slow steps - the take-offs are easy."
- "Went up 'hands-off' half the way."
- "Rode thru those bumps really well", etc.

Day's tally - 13 flights on 2000 ft (600 m) of rope to between 300 ft and 950 ft.

Saturday and Sunday again at Jerrys Plains, this time with my "younger brother", Iain, "Smacker" McDonald and Bill. Same reactions after the "newcomers" 2nd flights. We total up 31 flights on 2000 ft (600 m) of rope to between 500 ft and 1,450 ft.

By the following Sunday there are 10 of us, and we log 47 flights (200 ft to 1300 ft) in 6-1/2 hours: about 8 minutes between launches.

As of writing, we have had 115 launches. Wind conditions have been -

- smooth to light turbelence
- 20 m.p.h. headwind to 2 m.p.h. tailwind
- crosswind (90 degrees) up to 10 m.p.h.

We have had about 10 weak link breaks, from 20 ft above ground to 800 ft above ground, and the gliders have no tendency to pitch up. Kites used include: Magic II, Missile (with french connection), Meteor, Mega II and Probe. All have towed up well, although slightly less towing pressure has to be used on Mega II style gliders, as well as with lighter pilots.

Finally, I had a rewind drum/storage winch made: - Car starter motor geared up (down?) to a drum which reels in at about 1000 ft/min. This is handy, but not really necessary if you don't have to wind up the rope after each flight.

If any of you are interested in trying this system, here are a few tips:-

l) Read "Towing 1983" in May '83 "Hang Gliding" for basic details of the system.

ll) Read "Rope Tricks" in the same publication for an idea of what can go wrong if people (who presumably are used to the other systmes of bridles and towing) tow with too much tension and/or with multiple stage releases.

lll) Feel free to contact me on 065-724747 (after you have read the above articles) if you have any problems understanding the system or need details on the ropes an/or bridle system. If you can make it to Singleton at any time, a day on the strip can probably be arranged in advance.

At this stage, we are still learning as we go. Shortly, I hope to be able to put together an article on the Do's and Don'ts of the system.

The next step will be towing behind an ultralight. The June edition of "Hang Gliding" has some dope on this. The Duncans have got their 2-place trike going, and intend trying to tow behind it when they master flying it. (Shouldn't be long!)

Will this be the future direction of hang gliding? I know that I'll be looking for long, flat, clear strips of ground, rather than for high, steep hills with tracks to the top. Shouldn't be too hard to find in this sun burnt country of ours.
+
STOP THE PRESS:

Bill Pool goes 91 km (56 mi) to the coast, and Denis Cummings goes 42 km (26 mi) after tow launches. The Glennies Creek site was blown out at launch by ridge-top compression. Both tow launched in a paddock 2 km in front of the hill. Thermal streeting and strong tailwinds helped these mid-winter flights. Max height achieved was 5,000 ft A.S.L. after releasing at 1,600 ft A.S.L.
*
DEAR DONNELL
*
FIRST FLIGHTS
*
1983/09-02

Dear Donnell,

It's been nearly a month since I wrote and told you about the test flights we did with a dummy pilot here in the Price area, so I thought it was time to sit down and tell you about the progress (and mistakes) we've made since. By the way, thanks for answering my first letter so quickly and thoroughly.

After our dummy flight, which we deemed to be semi-successful, at least it took off by itself and flew quite awhile before bending a downtube on a pretty hard landing, I called Gary Whitman for his ideas, got all of what we thought were the best ideas from the Skyting literature and headed out to try this new form of getting up there.

If you'll recall from my first letter, we essentially copied Gary's Skyting set-up. On a pickup truck we've mounted a spring connected to a tension gauge reading up to 200 pounds that sits out in front of the driver. We designed and built an electric take-up reel for the rope. We have 2000 ft of 1/4" polypro, then 1000 ft of 1/8" polypro, next is our weak link which is #18 twisted nylon line and breaks consistently between 170 and 190 lbs. when tied in a sort of granny's grapevine knot we discovered. Then comes 50 ft of 1/4" polypro. We use a bridle similar to Gary's in that our release (three-ring circus) is attached at the towline's end and the bridle stays with the pilot after release. We used this type of bridle because we felt it was simpler (only one release to malfunction) for our first learning experiences.

Since this whole thing was my idea, although Dave willingly went along, I was elected for the first flights. Not knowing exactly what to expect, I decided what I wanted to do first was a series of small "bunny hops" to get the feel of what being pulled by this long rope was like. After arriving at our site (a two mile long road facing the prevailing wind with nothing on either side except miles of unobstructed landing areas) we set up and laid out about 1100 ft or our rope. We use a walkie-talkie mounted on the glider with a headset microphone under the pilot's helment and a regular C.B. radio in the truck for communication. Since I didn't want to let go of the control bar to press the talk button we simply taped it down so I could talk to the driver and he "talked back" by using tail light signals, one flash for yes, two for no.

For the first flight I told Dave to just pull me about 50 feet at about 5 mph so I knew what to expect the pull on my harness and the kite. He started slowly down the road and I held back, feeling the tension gradually build. The wind was straight in at about 10 and when I couldn't hold back any longer I had no choice but to run. Two quick steps later I was in the air flying solely on the elastic stretch that had built up in the rope. I climbed to about 5 feet and as the tension slacked off I leveled out and landed about 30 feet down the road. Wow! I couldn't believe how easy it was! I didn't know what to expect, but it was as easy or easier than taking off a hill. I was definitely excited! I told Dave to do another one just like it. He flashed me once for yes, so I got ready. Repeat performance, great!

At this point Dave came back to talk about things and we decided to try a higher flight and find a tension setting that would give us about a 500 fpm climb. I would climb to 200 or 300 ft and then release. We decided to use a tension setting of about 5 on our scale until I watched the vario long enough to determine if this was too much or too little. That should have been a tension of around 100 lbs.

Dave went back to the truck and I nervously got ready. This was it. Also the wind had died and I wasn't too sure about a no wind take-off in a glider I was a little too heavy for in 85 degree heat at 6000 ft elevation, but I wanted to do this flight. I hooked in, did a hang check and stood up. "Ready?" I asked Dave. One flash. This is it! "One, two, three, GO!". The tension built rapidly and this time I got about 6 steps before taking off smooth as a Cessna. Easier than I thought, but now I really had to fly this thing. I glanced at the vario. 300 fpm up, "Dave, hold this tension". The nose seemed high to a conventional hang glider pilot and I didn't want to overdo things. I had the bar very near the trim position, just slightly pulled in and every thing seemed fine.

Suddenly, at about 150 ft, the airspeed increased dramatically and I was climbing like a rocket. I thought it must be a wind gradient so I pulled in to get that high nose angle down and told Dave to slow down. What?, airspeed still increasing! "Slow down, Dave!". "Dave, slow down!". DAVE!!?? "STOP!!!". I looked over my shoulder at the radio and discovered a problem, the microphone cord had snagged on something and pulled loose from the radio, well that explains why Dave was happily speeding down the road while I was having such an exciting time. Now I was really getting high and Dave was showing no signs of slowing, so I decided it was time to do something. "Oh yeah!", I thought, "How about releasing? Good idea!" Then I noticed that the tow angle had steepened, the release line tied to my wrist had developed a good bit of slack. I took my hand off the bar to try to release. No good! Too much slack! My left hand wasn't strong enough to keep the bar at my knees so the bar immediately came up to my chin. I grabbed the bar again and stuffed it.

"Well, what do you do now you big dummy?" I really had misgivings about releasing the nose this high and with so much airspeed. Maybe I could take up some of the slack on the release rope by letting go for just a second and getting another loop of it around my wrist. Then I could release just as soon as I felt the tension lessen a little. "Here goes... It worked!" The bar came up again as I let go, but not as dramatically. It looked like I was directly over the truck and Dave still had a mile of road left and was showing no signs of slowing down. There was no possibility of letting go long enough to plug the radio back in so I was resigned to riding it out. At least I had good directional control.

Suddenly I felt a little less tension on the rope. Not wanting to prolong this any longer, I pulled on the release rope. "It worked! Now don't stall! Bar at trim position. Man things are really quiet at this speed. What a relief!"

The rest of the flight was routine and I nearly made it back to takeoff. After this much excitement I decided to call it a day (it was getting dark anyway) and think things over.

Well, I'm sure this rather lengthly description makes most of our (particularly mine) mistakes painfully obvious.

First, we neglected the possibility our radio might fail for any reason. It did and I paid by getting a pretty good scare. When Dave didn't hear from me, he figured that he was towing me at exactly the right tension to give 500 fpm up and just buzzed right along. I mentioned that the first portion of the flight felt about right. What happened is that Dave was watching me in the mirror for that portion and when he got his attention to the gauge, he noticed it was only reading about 2, so he gunned it until the gauge read 5. Some wind shear, huh? Anyway, we've decided that the pilot should keep up a steady stream of talk even if everything is fine and if the driver doesn't hear from him for about 15 seconds he should assume radio failure and stop. We'll continue this practice at least until we determine accurate, consistant tension readings. If foresight was only half as good as hindsight!

Second, I let my own instictive feelings get the better of me. After thinking about it, I realized there was no need for me to suck the bar in like I had. All that did was reduced the tension gauge reading and cause Dave to speed up even more. It also removed the safety cushion of being able to pull in to reduce tension momentarily so I could release. Dave said he was going around 30 mph for most of the flight. Who knows what my airspeed was! He thought I might have picked up a tail wind! Dave also said that the gauge jumped nearly to 10 a couple of times. Remember I let go of the bar a couple of times? Why the weak link didn't break I don't know unless the loading was so momentary that rope stretch took care of it. How much danger is there if the weak link goes when the pilot is sucked in all the way with the nose high? I haven't read anything about this particular possibility. The thought of a severe whipstall is what kept from releasing for so long. Hopefully, I'll recognize this situation from now on and simply let the bar slowly come back to trim position so the driver has time to react by slowing down.

Third, we didn't realize that the release line would get longer as the angle of the bridle changed, especially when my hand that it was tied to was on the bottom tube of the control bar. After thinking about this I decided that had I been flying at trim position, it would have been long enough to take some slack out of the rope. More on this in a minute.

Don't get the wrong impression that I was discouraged by this experience. It merely pointed out that there were things we really hadn't thought through as well as we should have. I've since spent a lot of time wondering what else we haven't thought out well enough. Perhaps it was just fools luck, but with everything we did wrong, the system behaved just like it was supposed to. No lockouts, no loss of control (just self-control) and both myself and the glider came through unharmed. It is very forgiving of mistakes.

Well, by next weekend my excitment had grown again so we headed out to our site. We had another pilot with us now who would take care of ground crew rewponsibility. This is really a bonus.

I decided I would first do a bunny hop to about 10 ft just to make sure everything felf OK. Conditions were again perfect. Ten mph wind straight in. I hooked in after preflighting everything and gave Dave the go signal. Two steps and I was gone. Dave had gotten a little carried away with the accelerator trying to give me a clean launch and hadn't really taken the wind into account so instead of going to 10 ft, I got to nearly 50 before he stopped. No problems. I released and glided down to the side of the road.

Feeling more confident now, we decided to try a tension setting between 2 and 3 (from my first experience that seemed like it would be about right) and I would tell him to speed up or slow down accordingly. As we had agreed, Dave would assume radio failure if he hadn't heard from me every 15 seconds or so and stop. As long as everything seemed OK, I would go up as high as I felt comfortable, tell him to stop and release.

I got ready and gave him the signal. Another beautiful takeoff. I fooled around with the bar. Just slightly pulled in from trim position felt most comfortable, at least I wouldn't stall while on tow. I was getting a little to the side of the road now, I made the correction and the glider came right back. Great! I did a couple of very small S turns. Everything fine. I checked the vario. 400 fpm, that was just fine with me. "Gee, I better say something to Dave!", I thought. "Dave, everdthing's great, keep going!" I kept my eyes glued to the vario, 300 fpm, 200, 100, 0, 100 down. "What's going on?" I looked down. The truck had stopped and the transition from tow to free flight had been so gradual I hadn't even noticed while I was watching the vario. Dave had done exactly what he was supposed to do. When he didn't hear from me, he stopped. No problem, except that while I had been watching the vario and Dave stopped, I had covered some ground. The next thing I saw was that I overflew the tow rope and watched the release disappear between my feet. "Release, Quick!" A familiar problem reared it's head. The release line had a lot of slack in it and it took three tries before I got off the tow rope. I was flying with my left and trying to release with my right while trying to see the release between my toes and knowing what would happen if the towline snagged on something while I was still attached. I know you know the feeling.

By the time I finally released I was pretty low and off line to the wind. I stalled a little high and did a quick turn to the right followed by a classic nose-in. No damage to the glider and I got a couple of minor scratches to show off. Reviewing the history of this particular glider, I've noticed a tendency for it to drop it's right wing when stalled above the ground. We need to correct this problem because not only are nose-ins embarrassing and sometimes painful, I don't like the idea of what might happen should it stall while on tow.

Anyway, we are going over possible solutions to the slack release line problem, most promising seems to be your idea of an auto-release line that pulls the pin if the top bridle line extends beyond a certain point (when the glider overflies the rope). If you have any other ideas on this they would be appreciated.

Well, this is where we stand right now in our progress. We plan to take things cautiously and one step at a time. Incidentally, I've read very little in the literature about crosswind take-off technique in the Skyting literature, how about a few tips?

This is all getting kind of long winded, but I'd just like to give you my personal thanks for developing this system and providing us with a quick, easy way to get some air. And thanks for so freely sharing your time and ideas with the rest of the world. Hope you get in the air again soon.

Scott G. MacKnight
Price, Utah
*
1983/09-03

Dear Scott,

Thanks for sharing your experiences with us. I plan to include them in one of the future issues of SKYTING.

It appears to me that one of your major mistakes was your decision to try to climb at 500 fpm on your first "real" flight with a tension around 100 lbs. You had just made two successful "hops" to 5 ft and should have calibrated your tension gauge so you knew where 60 lbs indicated. If you have nothing else, you could have calibrated the gauge by having one person pull on it. (60 lbs is approximately how hard most people can pull before their feet start to slide on the loose dirt.)

I, too, am surprised the weak link did not break. It was not because of the momentary peak in the tension. Any force strong enough to make your gauge read 10 had already stretched the rope. Perhaps this is just another illustration of the inconsistancy of the spring gauge. (Weird things have happened on mine, too. That is one reason I am so happy with the hydraulic gauge I have.) I do suggest that you tie a short towline to ground and pull on it till you break your weak link. Note the gauge reading at this time and you will know at what setting the weak link breaks.

There is no danger in breaking a weak link with the bar sucked in all the way if the weak link breaks at less than one "g". TEST YOUR WEAK LINK USING THE SAME KNOT YOU FLY WITH. You should be flying with a single loop of #18 nylon twine which breaks at about 200 lbs. From your description, you may have been flying with a double loop or something else that breaks at several hundred pounds. A break such as this could cause a whip stall and crash. You may have been in more danger than you realized.

By the way, a nose high attitude is normal while towing. (Read SKYTING No. 1 and No. 2 about the tilted earth concept.) And, yes, you should have gradually let the bar out to neutral (trim) position so your driver would have slowed down. I am surprised you did not have severe adverse yaw problems considering how fast you were flying and hard you were being pulled. What glider are you flying?

Now concerning the auto-release of a slack line. Usually there is not enough tension in a slack line to activate an auto-release line, you will have to figure out how to get two lines to pull the one pin. (See SKYTING No. 15 for one way to do this.) Or you can run your regular pull release line through a ring near your keel attachment point and then down your top bridle line to your release. By adjusting the amount of slack appropriately, you should be able to produce automatic releasing when the vertex of the bridle moves down too far. The problem I see here is how to release when your hands are on the down tubes during takeoff (there will then be too much slack). Perhaps you could coil the pull line up in your hand during takeoff and then drop the coil when you go prone. Obviously more thought is needed here if you want a truely reliable release system. (Skyting criteria No. 6.) You may prefer to go ahead with one of the more tested release configurations instead of perfecting the one you have.

Now concerning cross-wind takeoffs. I would recommend that you not try them yet. Wait until you have considerable experience with up-wind skyting takeoffs. By that time, I should have written an article on the subject in SKYTING. The reason I have not already done so is that the technique using modern gliders appears to be different than the one I learned for my standard Rogallo. I have not been flying my Gemini long enough to be sure what is the proper technique to use with the high aspect ratio gliders.

Thanks for your encouragement and please skyte safely.

Donnell Hewett
*
1983/09-04

Dear Donnell,

On August 15, 1983, Sherrill William, John Stokes and myself flew. With our skyting bridle (single release) 1100 ft of line including leader, and air cylinder to read pressure, I launched at 1:00 pm into good thermal action. We normally tow to 750 ft and release, but today all tows were in the 500 ft to 600 ft range. This was because of the length of our road and the up and down air. I got off the line at 500 ft and started turning in a 100 fpm thermal. This took me to 3300 ft and never got much stronger than 200 fpm.

I lost this thermal and flew back to our field, which we call our chimney on an up day. This field is up or down. Today it was up at this time. I found another 100 fpm up thermal at 1200 ft. This I road to 4000 ft above the field and road we use. This flight lasted one hour and six minutes.

Sherril and John launched after I landed. They worked a few thermals each on each flight. Their release was at 500 to 600 ft each. They were flying from 4 to 6 minutes on each flight. This is great from 500 ft.

Most of our flying has been in the afternoon late because of the heat, but this weekend we flew in the good part of the day. In thermal tow you go up fast and the car has to go and stop a lot, or in the down you just maintain.

I would like to tell you what I do when my Gemini starts to yaw. When the glider starts to come back to center, you jab the control bar against the direction of the yaw. This shifts the cross bar and keel pocket to stop the yaw. The other method we use is to slow the car. The jab method works. If you miss the first yaw cycle trying to get into your harness, then you can catch it coming back the other way. If you keep missing, your feet are the problem. It's from your feet being on the inside of the yaw. You need to get into your harness as soon as possible.

Donnell, I will write as soon as something good happens again.

Butch Pritchett
Finley, Tenn.
*
1983/09-05

A NEED FOR TOWING

Dear Donnell,

I'm a dealer here in Costa Rica and Panama for 2 ultralights and 3 hang gliding companies. I feel there is a need here in many areas for tow systems. I've had some experience in towing - but with the older system. This looks much safer - your experience proves it can be safe - depending upon the people working with it.

Bill Merwin
Costa Rica
Central America
*
1983/09-06

PLEASED WITH SKYTING NEWSLETTER

Dear Donnell,

Talking to you over the phone cleared up a lot of small details for me that would have taken a lot of paper and time to clear up by writing.

I forgot to ask you how your arm was coming along. I do hope it heals up nice and strong. (Ed: The latest X-rays show it has now healed properly.)

You say you're not an engineer (and neither am I) but from what I read in Skyting and from your diagrams of your new bridle system I am impressed. It looks and sounds like a lot of thought and consideration went into its design.

I am very pleased with your Skyting Newsletter and have a hard time waiting for the next one to arrive. I keep reading the back issues over again and always seem to find something that slipped my mind since the time I read it before.

There is a lot to be learned from your experiences and I am very grateful for your sharing your knowledge with me (us).

Fred Stoffan
Wattsburg, PA
*
WANTING WATER TOW INFORMATION
*
1983/09-07

Dear Donnell,

I've read about your way of teaching hang gliding - SKYTING - in the magazine Hang Gliding in May 1983. In Sweden we've a lot of sites but just a few with safe landing areas. The main reason are the woods (over 55% of the total country). I'm impressed of this system and also of that case that you can tow in water after a boat as well. I would be happy to have complete information in the theories of skyting. And if you know somebody in Scandinavia (Sweden, Norway, or Denmark) who have knowledge and experience of skyting. If not, I'm willing to come over and have the instructions myself in the beginning of 1984. USA is a great country. I know because I've been there myself twice and once in Maui, Hawaii. I've never been to Oklahome, but I know that "the Pan" is known for testing aircrafts. Looking forward to hearing from you soon.

Peter Magnusson
Swedish School of Hang Gliding
Goteborg, Sweden
*
1983/09-08

Dear Peter,

Thanks for writing.

You should contact Bjorn Montgomerie, Granbacksuagen 8, 178 00 Ekero, Sweden, who has also requested skyting information.

I wish you could come to Texas to see me, but such a trip is not necessary for you to learn to skyte safely. If you already have plenty of free-flight hang gliding experience, you should have no trouble learning to skyte there. Just read the enclosed material carefully and exercise appropriate caution so as not to repeat the mistakes of others.

Donnell
*
*

[Tad Eareckson]

1983/10
*
SKYTING NO.18
OCTOBER 1983
*
1983/10-01

SKYTING NEWSLETTER GETTING BIGGER

At first glance, this issue of SKYTING may appear to be two pages smaller than usual. But in actuality it contains one more page than normal. By printing on both sides of the paper, we are able to get 6 pages on 3 sheets of paper instead of 5 on 5. And since we already photo-reduce our pages to double the amount of printed material, this issue of SKYTING contains the equivalent of 12 regular typewritten pages instead of the usual 10.

The reason for increasing the size is that the amount of material coming in each month has been increasing. Also, there has been an increase in the number of subscriptions, so I am able to take advantage of higher volume printing discounts. (But postage is still the same because the volume is still too low to obtain bulk postage rates.)

Instead of increasing the size of the newsletter, I could have simply done more editing so as to weed out more fo the "fat". But this would take more time and effort on my part and could also reduce the "flavor" of the newsletter. Of course, if you continue sending in more and more information, I will eventually have to do more and more editing. Conversely, if you stop sending in reports of your experiences, I'll have to drop back to the five page newsletter.

Donnell
*
WINGTIP STALL PROBLEM
*
1983/10-02

Dear Donnell,

Hi! Susan and I just got back from a vacation in Colorado. I won't bore you with any details of now nice the weather was (beautiful), or how high the mountains are (whew!), but I thought you'd be interested in knowing that they are skyting in the Denver area! I spoke with Al Goden of Goden Sky Sails and they are using a skyting bridle with two 3-ring releases. He also told me of a situation which I'd not heard of before. He claims that you can lockout (aggrevated slip actually) with the skyting system. This is accomplished via a yaw induced wingtip stall. This always breaks the 150 lb weak link, so he does not consider it to be much of a problem. I'd like to know (as I'm sure you would) if anyone else has ever experienced this phenomenon. I never have.

I personally can't see how a wingtip stall could happen if you're flying properly. It sounds to me like they are fully pushing out (nose extremely high) and flying just below the break point of the weak link. The exaggerated angle of attack causes the wing to stall at a higher speed, so if the wind speed suddenly lulls, a stall occurs. If the wing should start to fall off to one side, it could look like a lockout. However, I feel that if you get to the high side of the bar and pull in slightly, you should be able to pull out of it without breaking the weak link. Remember to always fly like you're in a thermal. You can push out only so far before you stall, so don't be tempted to push out too far.

Henry Wise
Houston, TX
*
1983/10-03

Dear Henry,

No, I have not heard of a wingtip stall while on tow, but I can see it happening if you are trying to climb at minimum sink speed. Since this is very near stall speed, a wind gust or towline tension variation could induce a stall. If the glider is yawing at the time or has a tip stall tendency, then a tip stall would be expected.

Towline tension would not be a critical factor (i.e. they would not have to be towing near break point). However, the spinning glider could easily turn so far away from a tow that recovery could be difficult before breaking the weak link. (Depending upon pilot reaction time, towline stretch, weak link break point (150 lb seems low), and whether or not a winch or reel is used.) This would not be a lockout in the traditional sense, but could be very dangerous, especially if the weak link did not break.

The solution, I believe, is to keep the glider's speed well above stall - say 25 mph - and not over-control the glider so as to induce severe yaw. This probably means, "Don't push out too far on the control bar." (Perhaps this problem was encountered by Gary Whitman and explains why he said in bold face type, "At no time during the takeoff or flight should you push out." in his article in May Hang Gliding.)

How about it, readers, what to you know about this problem?

Donnell
*
1983/10-04

TOWING FATALITIES

There have been at least three U.S. towing related deaths reported this year. (If you know of others, please report them.)

The first was that of Dennis Guessford in May, 1983, in Watertown, N.Y. All I know about the accident was that he was "Auto towing".

The second occurred on August 29 at the Kleberg County Golf Course near Kingsville, TX, when 63 year old, Mrs. Elsie H. Colquhoun died from injuries she received when a member of her family was riding on a parasail tied to a pickup truck used to tow it into the air. Mrs. Colquhoun was reported to have fallen when she attempted to grab hold of the rope to steady the parasail's landing. Strong winds created an updraft and the combination of grabbing the rope and bouncing of the parasail caused her to fall and hit her head on asphalt.

The third occurred on September 5, 1983, near Hamlin, PA, when Mark J. Morgan "was riding the glider about 5:40 p.m. and apparently lost control of the controls and it plunged 20 feet to the ground as it was being pulled by a truck across the field."

The second incidence was not skyting related (or even hang gliding related but it could have been. There was no mention of the pilot being injured, only the ground crew member. I believe it demonstrates that everyone, not just the pilot, should be careful when working around towing equipment. No one is exempted from being seriously injured or even killed.

It is not known whether either of the other two fatalities were skyting related or not. Neither of the other two pilots had ever contacted me for additional information from their friends to decide to go out and "experiment" on their own. Whether these accidents occurred on skyting or conventional towing systems (the third accident sounds like a lockout), it is still possible that the "success" of skyting systems may have encouraged the pilots to try land towing without previously obtaining adequate background information. Please encourage everyone you know to learn all they can about skyting before actually going out to the field to try it. Who knows, perhaps these three persons would be alive today if they had done this.
*
1983/10-05

OPTIMUM TOWLINE LENGTH

Dear Donnell,

Bill Poole wrote to you last month re your "Skyting" gear. In the period between that letter and today, we started trying out your system, with the help of the article by Garry and Denise Whitman. (See SKYTING NO. 17 for article describing these experiences.)

When your reply arrived today, it was devoured. Apart from your progression scale of 1 to 10, I can say that we have followed your guidelines pretty closely - they are based upon safety and common sense. Both of us are H5 pilots with considerable X-country experiencd (4th and 5th in the Australian X-country league in 1982/83). Your system will find nothing but support from the reaction of pilots such as Rick and Shane Duncan and Ian Jarman. (Rick and Ian were in the winning Australian team at Tegelberg, coming in the winning Australian team at Tegelberg, coming in 4th and 10th individually).

Enclosed is a graph with calculations for selecting tow rope length (optimum), depending on strip length and wind speed (average). It assumes that 500 ft/min lift will be obtained with a kite under tow at 30 mph airspeed. It's rough, but has proved to be reasonably accurate in selecting what length of tow rope to lay out.

I also agree with Tom Bushell (Skyting No.14) that the 100 ft leader can be eliminated if you use a "low stretch" polyethylene/polypropylene bridle. Mine has been released under full pressure (about 200 lb) by a releasing carabiner (similar in action to a glider release) at the front point of the bridle, and there has been no "spring back". (This was done at 1000 ft to check for "loop the loop" reaction of glider under full load weak link failure.)

If we find out anything interesting at this end, I'll get it to you.

Many thanks and safe flying.

Denis Cummings
Singleton, N.S.W.
Australia

Equations:

LT=LS/(1+( (88 sin O)/500)(30-WS) )

h=LT sin O

where:

LS = Length of Strip (ft)
LT = Length of Towline (ft)
WS = Wind Speed (mph)
O = Tow Angle (degrees)
h = height of tow (ft)

assume:

Glider air speed = 30 mph
Glider climb rate = 500 ft/min

Optimum towline length for 3100 ft runway.
h (ft)
WS (mph)
LS=3100 ft
LT=1000
O=45 degrees
O=30 degrees

Optimum towline length for 5200 ft runway.
LS=5200 ft
LT=1500
*
AMATEUR TEST PILOTING IS DANGEROUS
*
1983/10-06

Dear Donnell,

As to amateurs and professionals in Hang Gliding, your R and D of Skyting as physics professor is as professional as you can get; but the amateur test pilot aspect of Skyting is very dangerous.

I'd like to see all tow and foot-launched glider pilots grounded until well engineered safety pods could be fabricated. In 1981 I received the following message of encouragement from the now legendary late great George Worthington, "Best of luck in the promulgation and fabrication of your ideas." And was greatly saddened to read of his fatal spin in at Owens Valley in Sept. 1982. His death was caused by structural failure of an ultralight he was really test piloting; and as he failed to pull the chute, possibly also by pilot fatigue, his age as a pilot, and I think he had a strenuous game of tennis on the very day that he spun in at Owens Valley. In Soaring Magazine, one of more writers had warned him of the hazards of test piloting untested aircraft. It is my opinion that the test piloting of the Skyting system should be left to experienced conservative test pilots equipped with well engineered safety pods. My safety pod papers are certainly in the amateur desing catagory even though I think most of the ideas contained in them are OK! However, as poorly designed safety pods would be hazardous to life and limb, there is no substitute for proper R and D, technical development, and engineering - best left to physics professors and engineers.

Skyting June 1982, No.2 - p.2 "not just pushing the limits but way past them", Dennis Pagen. His remark describes your much too full schedule of "Donnell Hewett's Priorities". Your mishaps, fractures, need-to-get-your-act-together, etc. indicate to me chronic fatigue stress, I hope you'll ground yourself way beyond September. You're sort of King of the Royal Mountain in Hang Gliding today and your loss would be great to people in all of your Priorities. And last but not least, some Biblical references I think are in a sense analogous to your situation, i.e. "Do you think somebody is trying to tell me something?" - Proverbs 29:1 and 2 Samuel 21:17.

Edwin G. Sward
Worcester, Mass
*
1983/10-07

Dear Edwin,

I agree, it would be best if professionals did the R&D work on potentially dangerous concepts. But frequently the professionals fail to appreciate the importance of certain innovation concepts. (You of all people should realize this.) If, therefore, all R&D work were restricted to professionals, many of the greatest ideas would never come to fruition. I am, therefore, opposed to "grounding all pilots" until well engineered safety pods are a reality". All too often the addage is true, "If you want something done right, do it yourself."

I agree my life is very busy. I would not have it any other way. Even when I am vacationing, I am dreaming up ideas to try. I do not agree that my accidents were the result of "chronic fatigue stress". The first was a result of my flying in conditions beyond my ability, the second was the result of impatients to try out kiting (moored skyting) on a glider I was not adequately a master of. In other words, both were cases of "pushing the limits and lack of patience". I hope I have learned that lesson.

By the way, thanks for the scripture references.

Donnell
*
1983/10-08

THREE-RING RELEASES AVAILABLE

High Energy Sports, 2312 W. 2nd St., Santa Ana, CA 92703, is now manufacturing three-ring releases suitable for use on skyting systems. These are professional quality releases at a very reasonable price. Currently two of the releases can be obtained for $25.00. (Prices are subject to change and shipping should be included.)
*
1983/10-09

XC TOW MEET BEING PLANNED

Rich Pfeiffer and Co. are currently planning to hold a 9 day hang glider tow meet in El Mirage, CA, around the middle of July, 1984. The plans are to use car tow and/or ultralight tow to launch the gliders and to employ a "sail plane" format for the competition. This is the same format used so successfully in conventional sail plane competition and is the result of decades of evolution of glider competition. By scheduling the competition in the "heat of the summer" not only are great flights expected, but great fliers from all over the world, who will be in California for the Owens Valley competition, will also have a chance to compete in this event as well.

As a "dry run" to help get the "bugs" out of this new form of competition, Rich is planning a meet this October 22 & 23. Call him if you want more information on this event. (714) 972-8196. I'll let you know how the meet turns out when I find out.
*
1983/10-10

"POP-THE-WHIP" PROBLEM

Rich Pfeiffer reported a "semi-lockout" incident which occurred while air towing a hang glider behind a Quicksilver MXL. They were using a 300 ft towline with releases on both ends and a skyting bridle. The problem occurred during a turn when the glider moved to the outside. It then became impossible for the glider pilot to turn back on track behind the tug. It was necessary to release the glider from tow.

This "pop-the-whip" effect is familiar to anyone who has done much water skiing. As the skier moves to the outside of the turn, he speeds up and is forced even further out until he is eventually almost to the side of the boat.

In the case of ultralight towing, the glider would be pulling sideways on the tug and in a banked turning away from the tug. This is obviously a very dangerous situation and requires an abortion of the flight before both glider and tug are forced completely out of control.

If you are air towing or plan to air tow, watch out for this problem. On a 300 ft rope, you don't have enough time to get careless.
*
RE-DISCOVERING SOME OLD PROBLEMS
*
1983/10-11

Dear Donnell,

Although I have not personally contacted you I am familiar with your skyting articles. I am a member of the Rio Grande Soaring Association here in Southern New Mexico. Joe Barfoot wrote to you and requested a series of your skyting articles. We have been trying out the skyting system. We have received your information and found it to be very informative. The most recent article with the latest bridle system has been working very well.

So far we have had only two tow flying sessions. On our first outing we used 1/8" polypropylene rope that was 500 feet in length. We were towing a 200 sq. ft Spirit. The first day we had four successful tows with no problems. We were towing to an altitude of about 300 ft.

One side note, as far as release mechanisms, we feel that the three ring release is the only way to go. It is fast, takes the drop shock well and is easy to make.

This past Sunday (Aug. 28) we went out with a 500 ft leader of 1/8" poly with 1000 ft of 1/4" poly for a total line of 1500 ft. This worked out very well with the launch still very clean. In order to launch we are pulling about 50 lbs tension on the line and then trying to resist moving forward. We have not really felt any line jerk or adverse bar pressures with this setup.

One thing, we are towing with the body tow line above the base tube. This is not letting us max out the altitude because the base tube receives a downward force at high tow angles. We have seen some pictures that show the rope below the base tube. We would like your comments on this method so we can possibly try it. The only critical time is right after launch when the glider may be climbing too fast, break the weak link and be in a good whipstall 40 ft high. This situation would not be good for longevity. If you are towing with the line under the bar and have no problems, we would like to be able to do that also.

Anyway, we have achieved 1000 ft AGL with our 1500 ft rope. Next we are going to try 2500 ft rope.

Notes on our towing:

We are using a hardware store spring tension gauge (0-200 lbs) to monitor line tension. This has proven to work quite well so far. We are towing at about 100 lbs line tension. It doesn't seem to matter on a single surface ship (we have towed a Spirit and a Raven) if the line tension gets to around 130 or even 170. The climb rate increases and the tips are flapping like a good dive.

The Comet will tow successfully at line tensions between 50 and 100 lbs. If the line tension is greater than 100 lbs, the glider gets into an oscillation that gets so bad the pilot has to release. The rate of climb at 100 lbs tension is about 500 fpm, which is quite acceptable. The rate of climb at 120-130 lbs is 800 but the glider is unstable. We are going to try my Streak 180 next time out so we will see if this problem is related to Comets or Double surface ships with floating crosstubes in particular. I have owned a Comet and one thing about them is when you get them in a fast dive they have an oscillation from going fast for an extended period of time. I have not noticed this on my Streak. We will find out.

We had one bad incident when we did not secure the body tow line to the center of the pilots body. This caused a lockout situation with the glider being uncontrollable. Fortunately - and re-emphasize this to all tow people - we had a properly sized weak link and it broke. The pilot recovered and it was just a scary story instead of a disaster. USE A WEAK LINK!

Our goal is to tow up to about 2000 ft and release into a good thermal and radio down from cloud base, "See you guys later". Radio communication is essential to tow ropes over 500 ft long. Also for serious XC. Thanks for all your help so far and looking forward to communicating with you again soon.

Dave Church
Las Cruces, NM
*
1983/10-12

Dear, Dave,

In answer to your questions, when the body line goes over the base tube it makes it hard to top out and when it is under the base tube it makes it hard to stay low. When you change from over to under, make your first few flights with fairly low tension takeoffs (say to 50 pounds or so) in order to get the feel. (Yes I do tow with the line under the control bar, and no I do not have any trouble. Others have reported trouble in pitch control, probably as a result of towing too fast.)

You seem to have rediscovered the adverse-yaw, over-control-oscillation problem. See SKYTING No. 12 for a more extensive discussion of a theoretical solution to this problem.

Donnell
*
1983/10-13

MISSOURI AIR TOWING REPORT

Ted Gilmore (Region 6 Director), Gary Whitman, Dick Turner, and Bob Black got together in Liberty Missouri recently to pioneer some air towing. The tug was an XC 1000 with Rotax 377cc (32 hp) engine (static thrust with 2 blade prop of 250 lbs, 160 sq. ft. wing area, 32 ft wing span, top speed of 55 mph, cruse speed of 35 mph, stall speed of 21 mph, L/D of 7:1, 12000 ft ceiling, 75 ft take-off distance, and 100 ft landing distance). They used a 200 ft, 1/8 inch polypro towline and a 200 ft, 1/4 inch polypro leader. Turner was piloting the tug and Black was flying the glider. During the fifth the tug got above the glider and the weak link broke, causing the leader to fly back into the skyter's face. Needless to say, the pilot was not happy about the situation, but he was able to land without injury.

It was about a week later before another flight was made. This time, Turner was out of town and Clift Wilson piloted the Tug. They had installed a three-blade prop on the ultralight to increase the torque; were using a 45 ft, 1/8 inch polypro shock cord; 200 ft, 1/4 inch towline; no leader (to prevent a repeat of last time); and were towing off the J-bar at the tail of the ultralight. On the first flight, the ultralight flew too fast and the glider pilot could not keep from climbing on up. A vertically divergent flight soon developed with the glider going down. Again the weak link broke. This time the pilot was hit between the eyes on the bridge of the nose by the bridle fly-back. He was able to land without further injury, but no more flights were made that day.

The glider pilot decided to go back to using a leader between weak link and bridle. It was also decided that the ultralight towing should be performed with a minimum of 300 ft of seperation between tug and glider.
*
QUESTIONS ON TOWING RIGID WINGS
*
1983/10-14

Dear Donnell,

Could you please let me know the possibility of towing a rigid wing (very similar to your Fledgling) with drag rudders. How would the bridle be set up? Would the lack of weight shift affect your non-lockout system?

I hope the hurricane didn't cause you too much trouble.

Frank Smallman
Glen Innes, N.S.W.
Australia
*
1983/10-15

Dear Frank,

No one has reported skyting a rigid wing glider to me. See Hang Gliding, June 1983, "AIR-TO-AIR", for experiences of air towing a Fledgling. There they tie the tow rope directly to the nose of the glider.

My opinion concerning skyting a rigid wing glider are as follows:

(1) The object of skyting is to mimic free flight. Therefore, if you apply the eight skyting criteria to your towing situation, your glider should perform under tow essentially the same as in free flight. The fact that you are using drag rudders should not matter.

(2) The bridle should be a center of mass bridle (I do not recommend towing from the nose as mentioned above.) such as a standard 2:1 skyting bridle. The attachment points should be normal, i.e. the pilot's center of mass and the glider's center of mass (a few inches in front of the hang point makes very little difference).

(3) It is my understanding that the Fledgling type of glider uses both weight shift and drag rudders. If this is true in your case, the skying bridle would distribute towing forces the same as gravity distributes its forces and prevent any lockout tendency. (See the theory on lockouts in the skyting literature.) But if you are sitting in the glider as in a conventional glider so that you and the glider always move as unit (you do not shift your weight), then you should devise a bridle that acts as closely as possible through the center of mass of your combined glider-pilot system. In this case you whould attach the towline directly to your glider. As the tow force pulls on the glider, the glider pulls on you and everything here is that as you climb and your tow angle increases, the point of attachment needs to shift in order to keep the towline force acting through the combined center of mass.

Donnell
*
AVOIDING THE "PITFALLS"
*
1983/10-16

Dear Donnell,

Enclosed are some notes and sketches that outline and illustrate some thought that I had after reading "Skyting, the Pitfalls". (July/August WHOLE AIR)

Please note that I have no experience at all with towed gliding and almost none with foot-launched gliding. But I do have enough gall to make up for it and herewith submit my earth-shaking ideas.

1. If the weak link is made part of the release mechanism a new one can be installed with no trouble at all and could even be sized to match the glider and pilot at every launch. With a weak link between manual and auto-trip, a new one can be used any time without cutting, tieing knots, etc. Maybe some kind of well-calibrated plastic ring could be used?

2. Since the bridle you describe already has two releases (one manual and one automatic), why not add one more automatic release so that if either the top or bottom release lets go prematurely, the other will release. If the weak link breaks, the lower release trips and the entire assembly falls away.

3. If the manual release mechanism is designed to stay with the glider (with the release cable neatly secured to a down-tube) there should never be any "finger sandwich" or trouble with the release line tangling the tow line. If you trip the manual release (or if a release trips accidentally or if the weak link breaks, the manual trip device stays with the kite - no burned fingers, no hangman, no tangling with kite or pilot.

4. If a spreader is installed between the upper an lower halves of the bridle, it may reduce interference between the bridle and the control bar.

I am very interested in the future of skyting because I expect to be moving to southern New Jersey soon and will on longer have a hill to jump from as I do here in upstate NY. Keep up the good work and don't blame me if the above ideas stink.

Keel
Manual Release
Manual Release Line
Weak Link
Auto-Release
Auto-Release Line
Towline
Auto-Release Line
Auto-Release
Pilot
+
Keel
Manual Trip
Calibrated Weak Link Ring
Bridle Line (no weak link)
Auto Trip
+
Weak Link
Auto-Release
Spreader
Auto-Release
+
Max Venus
Greene, NY
*
1983/10-17

Dear Max,

Your suggestions are not as far out of line as you might think. Let me reply to each:

1. The key word for weak link is "infallible". If it were incorporated in the bridle, it could possibly tangle with the glider and fail to completely releae. Even if it worked 99% of the time, the 1% failure could be catastrophic.

2. Your tripple release suggestion has already been implemented. (SKYTING NO.15)

3. Many pilots are already using a pull line or a cable release that stays with the glider.

4. You are the first to suggest a spreader bar on the bridle, and although you design does not consider the 2 to 1 ratio of the lower and upper bridle lines, such a spreader could possibly be used. I will have to give it more thought to make a realistic evaluation, but my gut feelings are (1) making the bridle lines longer will have essentially the same effect as using a spreader bar. (2) the spreader bar could fly back in the pilot's face if the towline should break, and (3) if one of the auto-releases failed, the bar could fly around and hurt the pilot or damage the glider, or it could become tangled with the glider.

Thanks for writing, and keep your mind inventive.

Donnell
*
1983/10-18

TOWLINE SPLICES

Ted Gilmore has made some suggestions for splicing towlines. If you simply tie the ends together, the splice will not last long because of the wear of dragging it along the ground. (It is also a weak splice because of the knot, some knots being weaker than others.)

In the case of a hollow-braided polypro rope (ski rope), do not melt the end of the rope either with heat or with a hot knife. (To do so makes a bulge which causes excessive wear when the rope is drug on the ground.) Simply cut the ends with a sharp knife. Then use a fid (a pointed tube, which you can make from tape if you have to) over the loose strands to slip each rope inside the other:

For nylon rope, use beeswax impregnated thread to wrap the parallel lines and then cover them with heat shrink tubing:
*
1983/10-19

HINGED ARM TENSIOIN GAUGE

Dear Donnell,

I think your SKYTING Newsletter is just great. Keeping everyone in touch is what keeps enthusiam up.

Around here most of the kids still want to jump off a cliff. But I think that I am educating them. The only real problem is finding a permanent tow site. We work will in one field, and then in another, but something always happens to make us move.

The only problem we are having is the weak link. We are breaking too many. But I am afraid to strengthen them. Safety first. Our problem is not having a tension gauge on the rope. That, I think, is an essential. Otherwise, the driver is at sixes and sevens all the time. We just tell them to drive up crisply to 25 mph and hold it there. This works about 50% of the time. The rest of the time we are breaking something.

The other day my boy towed me. The usual. The start was too fast: the weak link broke at 15 ft up: I stalled; and on coming down I bent another bar. At $20 per bar to replace this gets rather old.

I am designing and building a tension gauge that should be the cat's meow. The idea is to use bungee cords and mechanical advantage. You have a hinged arm. The bungees attach at the top of the arm. The tow rope attaches one quarter of the way up. You calibrate by figuring that a 25 pound pull on the bungees - which is easy to get - equals 100 pounds on the tow rope. The bungees move four times as far as the rope, which also helps in accurately calibrating and in watching the gauge as you drive accross a bumpy field.

When the guizmo is done and operable, I shall send photos and drawings. What got me started was your latest issue - saying that mechanical is not accurate enough and that the way to go is phenumatic for $150. I would love to have a pneumatic cylinder rigged up - and just watch a gauge in the cockpit (driver's seat), but I don't have one readily available and I don't want to sink in 150 bills. However, if you locate a supplier for pneumatic cylinders and gauges, publish it, so I can order if and when the long green comes more available.

It is a gorgeous day ourside and I am off to my training hill - to do some hill flying until I get the tension gizmo rigged. But my heart is in thermalling, and that means towing.

Lindsay Fischer
Colorado Springs, CO
*
*

[Tad Eareckson]

1983/11
*
SKYTING NO.19
NOVEMBER 1983
*
1983/11-01

SERIOUS SKYTING ACCIDENT

by Gary Rieck
Sterling Heights, MI

This letter is to report an accident and structural failure which happened on Sept. 3, 1983 using the skyting towing system. Being new to towing we were trying to move cautiously and limit any changes, modifications or improvements to one thing at a time.

The first time out we tried two low takeoffs to about 50 feet. The tow rope passing over the base tube of the control. Everything worked successfully. Before we had an opportunity to get out a second time we learned of the "3-ring release" through an article in Whole Air Magazine. We built one of these to be used at the pilot's harness, leaving the "horse fittings" hardware for use on the keel. (No fingers to be eaten up there.)

Prior to launching with this new release, the pilot held the kite at various angles to the tow rope. This was to insure there were no interference problems and that all the bridle lengths were O.K. When holding the kite at very high angles of attack relative to the tow line, he found that the "automatic" release line for the keel would get tight and release. To satisfy himself that he could get high with the rope through the bar, he lengthened the auto-release rope about 6 inches. This was tested with a practice release on the ground and worked fine.

On the first tow of the day, as he reached 300 or 350 feet of altitude, he noticed that the auto-release line to the top fitting was about to get tight and release. Therefore, he gave a pull on the 3-ring and everything worked well.

Prior to the second flight he again lengthened the auto-release line in an effort to get higher. This time he did not discover he had lengthened the release line longer than the bridle line. This made it impossible to release the keel.

During the tow everything worked well until about 400'. At this point the pilot released the harness tow attachment (3-ring). The keel could not release because the auto-release line was too long. The kite nosed down and began to speed up. At this point the pilot pushed out very hard! The kite leveled very briefly, then pitched up violently.

At this point the kite failed at the cross bar fittings at the keel. One wing folded in next to the other semi-trapping the pilot inside. After about 150 feet of free fall the kite began to spin like a maple tree seed. About this time the pilot deployed his chute. With the descent of the kite slowed by the spinning, the parachute and kite were falling at almost identical speed, although the kite was going slightly faster. Before the chute could inflate, the kite hit the ground.

During the entire tow, the force in the tow line never exceeded 125 pounds per the hydraulic pressure gauge we use with our cylinder. Most of the tow was at 105 pounds.

Apparently when the kite pitched up, the downward inertia of the plastic hose used with the "horse fitting" was enough to release the keel. The weak link did not break, and it should not at 125 pounds.

The pilot was taken to a hospital, X-rayed and released with no broken bones. He did however have a severely sprained back. One very lucky pilot!

We all realize it is obvious that the automatic top release line must be shorter than the bridle line. It certainly wouldn't hurt to stress that point in any future articles. If it happened to us, it can happen to others. I certainly hope the reporting of this accident can help prevent any similar happenings to others.

ACCIDENT SUMMARY

Pilot: Dave Ramirez
Phone: (313) 582-6238
Experience: 10 years
USHGA #: 30,097
Kite: Bennet Lazor II, 174 sq. ft.
Location: Rockwood, Michigan
Date: September 3, 1983
Injury: Severely strained back
Witness: David Curtis, (313) 979-3305, USHGA # 14,989
Driver: Gary Rieck, (313) 264-0085, USHGA # 7526
*
TOWING IN GERMANY
(3 FATALITIES)
*
1983/11-02

Dear Donnell,

Bjorn Montgomerie of Sweden's letter in Skyting Nr. 16 reminded me that I should have contributed to Skyting months ago. Bjorn mentioned an international tow meeting in Waldeck West Germany. As the German delegate to CIVL and member of the Hang Gliding Committee of the National Aeroclub of Germany, responsible for tow launching (technique and training). I organized this meeting after the CIVL-Meeting in Schwangau Tegelberg.

The objectives of this meeting were: (1) to exchange information between countries where towing is already practiced and (2) as a source of information to countries interested in towing. The delegates of: America, Australia, Belgium, Denmark, England, Finland, France, Norway, Sweden, South Africa, and Ungarn were present.

Denmark, Finland, and Germany presented towing systems. The system of the Danish delegate consisted of a heart bolt connected towline with a cable release. The pilot being seated and using a trike for starting (trike is left behind). Finland developed a harness towing system similar to one presented by Germany. Germany also presented a system that divides tow-force in two, connecting to harness and keel.

I presented the Skyting system (horse release) and showed the two unsuccessful starts mentioned in Bjorn's letter. They were nationally televised, one including a tree landing with a camera attached to a helmet!!

The meeting was, apart from some organizational mishaps in regard to information exchanged, a success (I hope for everybody as much as for myself).

Finland reported that their national championships 1982 were tow launched. To be sure: not a towing championship, but a national hang gliding competition with tow launching as a means of getting airborne. Pilots in this meet could qualify for international competitions.

Apart from the harness tow bridle, the Fins are car towing using a hydraulic tensiometer and an automatic, as well as manual release, operated by the driver. Sometimes they tow without an observer because of lack of personnel. Then the driver controls tow pressure with an acoustic signal initiated by the pressure gauge. He accelerates to a set pressure using the optic gauge and then varies the speed to keep the acoustic signal constant.

Now to our Skyting experience. All our training is done using a skyting bridle. First we used the horse release and now, after some serious mishaps we have changed to a three-ring release, triggering the keel release first and having an auto release to the pilot. For additional safety we also use an additional auto-release running from pilot to keel. We found this to be necessry after a malfunction of the old keel release.

The pilot released his line, the drag chute opened, seeing this the winch operator assumed that all attachments were away and pulled on full power to regain the rope. At this time the rope was still connected to the keel. Just as the pilot tried to release manually, full power to the keel jerked the glider into a vertical dive. The pilot was thrown into the sail. At this instant, the bolt holding the crosstubes together sheared off and the glider folded up, spiraling in a vertical dive. The pilot could not throw his parachute. When he finally managed to get it out, it did not open properly. He then managed to grab the lines and jerk at them frantically until it finally opened. All this happened a lot quicker than it took to write it down here. The pilot released at 200 meters, the chute finally opened at 20-30 meters slowing him down to a soft landing, unhurt. Since I am that pilot, I'm now celebrating my birthday twice a year.

With the old bridle we also had a number of near misses. In one tow the upper towline and auto-release line looped around the pilot's neck after releasing and the winch operator, trying to regain the towline pulled the pilot's head onto the A-frame base, choking him.

The first change we made, was to extend the keel ring outside the front wires to stop entanglement. (Keel extension line.) Now, using the ring release, we have only one problem: topping out, the top rope runs alongside the pilot's head and soon touches the frame base.

We have trained about 10 instructors on Skyting and they in turn train FAI-Safe-Pro level four pilots. There are other instructors, outside the national airoclub using a purely harness type of bridle.

Since towing became legal in Germany on 5 May 1982, we have had three towing fatalities.

One was due to a lockout using a one-point (heart bolt attached) towing bridle.

One was on a harness type bridle. The glider being in a stalled attitude from the start. Then a rope failure occurred and no corrective action was made by the pilot. After whipstalling, the glider went into a vertical dive, hitting the ground slightly negative.

One was a 61 year old pilot not reacting while under tow. The winch operator decelerated, then emergency cut the towrope. Still no reaction by the pilot. It appeared he was unconscious. The glider landed on its own relatively smooth. The pilot was dead. An autopsy showed he had had a heart attack while under tow.

We are now reviewing our training program and holding a compulsory training class for instructors. All fatalities happened during initial towing instructions to experienced foot launch pilots. In the first two accidents there was no reaction by the pilots. In a number of incidents, the pilots, although they are all experienced, show no reaction in situations where they have been definately told what to do. It seems we are going too far too soon.

On the positive side are the many hundreds of starts performed each weekend. The first competition being solely tow launched. It will be in accordance to the FAI regulations. Primarily the Skyting bridle will be used.

At the CIVL meeting it was suggested that the Cypress Gardens Championship should be upgraded. As long as FAI competition rules are applied and cross country flights are made possible, there will be no objections. And if this is the case, there will be a number of European countries participating.

Well, Donnell, this is all for the moment. My first subscription year is over, therefore I enclose a cheque for the next 12 months. Although we had a number of problems, we had great help in solving them from your newsletter.

There is a chance that I might be in Florida next year. Maybe I can extend this by a visit to Texas to have a look at your towing. Best regards and safe flying.

Peter Roth
Neu-Isenburg, Germany
*
1983/11-03

Dear Peter,

I appreciate the report of towing activities in Europe. Although I have received inquires from others, yours is the only report I have received.

I was saddened to hear about the three deaths in towing there in Germany. (There have also been three towing related deaths here in the U.S. See #18.) It sounds like two of the three deaths were the result of violating the Skyting Center of Mass Criteria and the other was a heart attack. (Skyting No. 3.) Apparently more emphasis should be placed on skyting THEORY and meeting the skyting CRITERIA, so pilots will understand better what to do and why they should do it. I am not aquainted with the FAI towing regulations, so I can make no comment regarding them.

I thank God that your life was spared in your brush with death. I am amazed that there was sufficient force to shear the cross-tube mounting bolt without breaking the weak link! What weak link breaking point are you using? It also looks like your winch operators need to be more careful when they "lock in" to take up the falling towline. Here's hoping we can get together in Florida or Texas next year.

Donnell
*
1983/11-04

TOWING - SOME DO'S & DON'TS

by Denis Cummings
Singleton, N.S.W.
Australia

After writing my previous article "Towing - A New Era", I received from Donnell Hewett a full set of back copies of "Skyting magazine. I recommend them, plus ongoing subscriptions, to anyone who wants to go towing a hang glider. The slow steady development of the "skyting" technique between 1979 and today is well documented in these publications, and the theory, experiences, and problems discussed are very handy background information.

On the safety side, Donnell Hewett has proposed that any towing system or method can be considerted "safe" as long as all eight of his "Skyting Criteria" are met. These eight criteria are:

(I) Constant Direction of Tow
(II) Constant Tension
(III) Uniform and Proportional Distribution of Tow Forces
(IV) Correct Attachment Points
(V) Slow Transitions
(VI) Reliable Release
(VII) Infallible Weak Link
(VIII) Safe Learning Method

Following about 400 tows with our system, and being around while about 200 tows have been done on the 3 other (similar) systems, there appears to be a small number of regular potential dangers emerging. They can usually be traced to the breakdown of the above 8 criteria. My own check list goes like this:

a) Gear:

I) Tested, infallible weak link.

II) Low stretch, free-running bridle.

III) Reliable release.

IV) Longest practical tow line, of sufficient stretch under full load to take out most "bumps".

V) An accurate gauge to measure tow tension.

VI) Communications between driver and pilot.

VII) A tow vehicle that can accelerate smoothly from stationary to at least 50 k.p.h. (31 mph)

b) Strip:

I) Of safe width and the longer the better - anything less than 1 km (3000 ft) long is not much good in flat country.

II) Cleared of ANY possible snags (limbs, weeds, tall growth) along the tow path of both rope and vehicle.

III) Smooth, obstacle-free path for tow vehicle so that it can obtain and maintain a comfortable 60 k.p.m. (37 mph)

IV) Wind socks/streamers at take-off/landing end and opposite starting position of tow vehicle.

c) Towing Proceedure:

I) A system of signals/calls known by both pilot & driver. e.g. "STOP" means a complete stop by the driver; "GO", "SLOWER", and "FASTER".

II) A proceedure prior to the tow to take up all tow rope slack and allow the pilot to become comfortable with the glider, his gear and the wind.

III) An experienced driver, who is capable of giving a smooth take-off in either light (zero) wind or in strong wind as well as reacting efficiently to tension fluctuations in the tow rope during tow.

IV) A proceedural check by pilot and driver at the end of the tow to ensure that the release (or cable/weak link break) has been effective.

V) An understanding between pilot and driver of the safe proceedure for descent of pilot if he is unable to release from the tow rope.

VI) Pilot control in moderation while under tow. (Too much input by pilot can result in pitch, roll, and yaw oscillation - these usually smooth out when pilot input is stopped.)

VII) Common sense airspace used so that gliders at take-off or under tow are not endangered by free-flying pilots. (Remember, the tow rope is nearly invisible until it is close.

VIII) All other hang gliding pre-take-off checks.

When starting from scratch, with only a magazine article and an American phone number for reference, I felt the need to apply all my experience of hang gliding (not-towed) to ensure that each progressive step was made with the minimum chance of danger. Having also had a little experience with glider tow launching helped considerably.

The first tows were experiences for both pilots and drivers as we learnt firstly the basics, and then started to appreciate some of the minor problems which can be associated with tow launching. After 2 months of towing, and seeing 30 to 40 pilots experience their first towed flights with the "Donnell Hewett" bridle system, I am convinced that towing can be safer than cliff/hill launching. The disturbing part is the CAREFREE ATTITUDE of pilots (myself included) towards use of this POTENTIALLY DANGEROUS activity.

Pilots who wouldn't normally take-off from a 20 foot sand dune without doing a glider check and a hang check, have been seen jumping into a mates' glider, behind an "unknown quantity" towing system and yelling "GO! GO! GO!"

Some potentially deadly errors observed:

1 - Untested weak link sent pilot (me) into 90 degree nose up attitude as the rope broke (yes - the rope, not the weak link) under a very gusty, strong tow. I had changed weak link rope type and the two had "looked the same". On testing, the new weak link broke at about 350 lbs - nearly 80% over the recommended 200/230 lb weak link we had been using.

Lesson - test the weak link material you intend using. Make sure it will break at the correct load - OVERSTRENGTH WEAK LINKS COULD BE DEADLY.

2 - Pilot using springy bridle rope released under full load. The release carabiner and ring hit him under one eye, requiring medical attention and about 1 week in hospital. He was lucky not to loose an eye, or to have been knocked unconcious.

Lesson Don't release under full load UNLESS ABSOLUTELY NECESSARY. and use low stretch bridle rope - preferably 6 mm or 8 mm diameter prestretched braided yacht rope.

3 - Pilot didn't put legs into harness leg straps. Was hanging in harness by the armpits - couldn't get into prone, etc. He landed safely, but could have been killed in a freefall.

Lesson - DO FULL HANG CHECK and GLIDER CHECK before each tow.

4 - Various instances of releases not releasing and release ropes either unattached from pilot or broken. Some cases of release ropes being tangled with either the release or the tow ropes. Manual pulling in of the bridle and release usually sufficient to affect safe relese - occassionally necessary to fly the tow rope to the ground.

Lessons 1. INSIST ON USING A RELIABLE RELEASE. 2. PREFLIGHT THE BRIDLE/RELEASE/TOWLINE ASSEMBLY PRIOR TO LAUNCH EACH TIME.

Beware also the compounding of errors, such as: The tow tension indicator is very crude. It is mechanical, and tends to stick a little as it changes readings up and down. The weak link has been breaking reasonably regularly. This is inconvenient. A stronger, untested weak link is used. Tow tensions are then increased, but the tension indicator doesn't readily detect these overloads and with the overstrong weak link, a potentially dangerous system is being used.

Don't get me wrong! Tow launching can be made safer than any other method of hang glider launching. BUT ONLY IF WE, THE PILOTS, TREAT THE SYSTEM WITH THE CARE AND RESPECT THAT OUR LIVES DESERVE.

DON'T USE UNTESTED OR UNRELIABLE GEAR. DON'T LAUNCH ON A RESTRICTED OR UNSUITABLE STRIP. DO USE ACCEPTED PILOT/TOWMASTER COMMUNICATIONS, TOWING, AND EMERGENCY PROCEEDURES.

For pilots who are towing, or who will be towing soon,

- how about reporting those accidents (e.g. eye injury)?

- how about reporting any incidents that didn't end up as accidents? Maybe it will stop someone else from having an accident and/or injury. Accident reporting proceedures are in the "yellow folder".

For our State and National executives for consideration:

-are tow-launched pilots covered by our consitiution?

-how effective is our insurance cover?

-how are tow-launched pilots effected by present/future ANO's? ((Air Navigation Order))

-how are liabilities between pilots and tow vehicle drivers possibly distributed?

-will the Safety Directors/Co-Ordinators/etc. get involved in towing or are we to see a seperate "towing group" as previously?-when will the "Towing Nationals" be held?

Get up there safely and stay high!
*
1983/11-05

BELLY BAR

Dear Donnell,

Having just read your recent article in WHOLE AIR Magazine on towing, I would like to offer a few ideas for solutions to some of the problems with the skyting method. As a veteran supine pilot it occured to me that using a seated arrangement might just solve a couple of problems. Flying seated would keep the pilot's head away from the keel line and release line too. Also the body bridle might not interfere with pitch control if an offset "belly bar" were used instead of a straight base tube. I have bent my own "belly bar" with a 6 inch offset center section) using 0.125 wall thickness tubing. It works fine. I mounted it so that the offset part is at a 45 degree angle forward. The body bridle line could then be passed under the base tube.

Actually, I'm glad I live where there are mountains to launch off of. But more power to you flat land pilots.

Kenny Maxfield
Moyie Springs, Idaho
*
1983/11-06

NEW BRIDLE RIPPS

Dear Donnell,

Tried Skyting for the first time and had three good flights. There were four people, none had ever seen towing done before.

After setting up my Raven 229 and putting on training wheels, we hooked up the bridle. Having someone pull on the rope to see if it was set up right, we had several premature releases before getting the auto-release lines right. The bridle was then tested to release under some pressure and we were ready to tow.

For the first flight we fed out 200 ft (approx.) of rope and tied it to our hydraulic cylinder. Being unable to find a weak link we decided to go without. The driver was instructed to not exceed 80 lbs pull. In almost calm conditions we started our first flight. I pulled back until I was forced forward and was airborne in about 5 steps. It was smooth and easy with a climb of about 200 fpm until our bungee broke.

On the second flight we left out the bungee and went the other way down the runway. No wind, or so I thought. It took much longer to get off and never climbed very fast although the truck had to go much faster.

On the third flight I told the driver I would release before he got to the end of the runway. Using around 300 ft of line I had a nice takeoff and climb out, and topped out about 1/2 way down the runway. Instead of waiting for the truck to slow down or pull in on the bar, I released, turned around and flew back to where I set up. Great! Nice day of flying, only when the ground crew got back the bridle was wrecked. (Ed: This is the new skyting bridle described in SKYTING NO. 15.)

The auto-release lines pulled right out to the eyelets and tore half-way down on both upper and lower webbing.

We have taken the bridle in and are having one built that is a little stronger. Putting eyelets in where the lines run should help. Have to remember not to release under tow unless necessary. Let you know how we make out in the future.

L. Lawrence
Moose Jaw, SASK.
Canada
*
SMALL CAR TENSION GAUGE
*
1983/11-07

Dear Donnell,

We're meeting your 8 skyting criteria (#3) and are in the "production mode" for our towing now. Our towing is now consistently achieving 3-400 ft altitudes on 6-700 ft lines at our 2400 ft tow site. Three of us made 19 flights Sunday, August 14 (about 8 hours at site - includes lunch break).

My Condor averages 50 sec, Greg's Comet 70 sec, Mario's Sensor 100 sec; best flight so far is Mario's 1:57. No soaring, but lots of thermals. Those contacted are zero sink for Condor or brief rise for Sensor. Towing in (and out) of thermals is a bit disconcerting for towee and tower: High climb rate like an over 100 lb pull but tow vehicle is moving slowly and only reading 50 lb. Out of thermal tow force shoots up but glider looses its climb... I guess, if you've got a substantial percentage of your climb, you should release to retain thermal, rather than prolong climb in non-thermal and/or down air.

We're all using Yarnall releases on 2:1 skyting bridle arrangements.

Tow vehicles: Mario's FWD, manual transmission Subaru Wagon. Tension gauge is garage door spring installation like Gary & Denise Whitman's (HG May 83). My FWD, MT Lynx 2D sedan uses $2.19 coil spring from local hardware store for tension gauge. Installation on Lynx is touchy because of very light construction. Roof oil cans to touch. Bumpers not attached directly to car but merely stuck into energy absorbing cylinders which are then bolted to unit body. (Asked Ford how much pull before bumpers fall out, but no answer.) The 1/4 inch nylon tow bridle is slip-looped around the energy absorbing cylinder so most of the tow force is reacted out by friction.

Shifting manual transmission to 2nd after glider gets off provides slow transition at initial climbout. Our radio transmission from glider to tow to start slowing down provides slow transition prior to release (of course running out of room to tow provides automatic transition).

Towline is 1/8 inch poly ski rope. Weak link is the #18 braided nylon, with barrel knot - it breaks at maybe 210-220 pounds. No weak link break in last 25 flights. We're towing at 80-100 pounds.

The weak link is a loop through small loops in the 1/8 inch poly. The thin weak link cord is creasing the towline loops such that they'll probably fail. Should we be using small thimbles? Found that if we tied 1/8 inch line in knot around weak link loop, the knot "swallowed" the weak link string which subsequently "choked" the heavier line and actually severed it before the weak link broke.

Mario's flown both Comet and Sensor on tow and reports Sensor much easier to climb out although both gliders are susceptable to roll/yaw oscillations.

Jerry Martin
Dayton, OH

P.S.

Yarnall release was $50 three years ago. Very good quality - ejects towline ring strongly over all conditions of slack or tensioned towline.

Yarnall Techtonics, Inc.
Canandaigua Airport
2440 Brickyard Road
Canandaigua, NY 14424
(716) 394-6430
+
Four point rack for glider.
Required due to Lynx flimsy construction.
+
Conduit X
Bungee
Tape flag
(100 lb)
Tape Mark

Weak link string in plastic tube under car transmits spring movements.

1/4 inch poly
Ring
Spring (7 1/2" good to 16" for 100 lb load)
1/8 inch line
+
Bumper Plugged into Cylinder
Cylinder Bolted to Car
Eye
Spring
+
45 degree Angle
*
1983/11-08

Dear Jerry,

Keep tying your weak link to a loop of towline and leader. Do not insert a ring or thimble - especially on the towline (unless you also attach a drag chute). When the towline is stretched to the point of breaking the weak link, considerable energy is stored in it. When the weak link breaks, this energy is transmitted to the metal ring or thimble. The result is a metalic projectile shot toward the ground and the tow vehicle. Before we learned this lesson, a ring tied to the vehicle was shot through our glider's sail when the knot became untied under tension. We were lucky the pilot was not hit.

Donnell
*
SKYTING IN NEW ZEALAND
*
1983/11-09

Dear Donnell,

Just a note as promised when I ordered your towing bridle.

We attached to the bridle 100 ft of Marine Red (a non-stretch rope 4 mm Dia) then a weak link (designed to break at 230 lbs) to 300 ft of 340 kg breaking strain nylon which was attached to the car via a hydraulic pressure readout system. Basically the system is as you recommed, even to the training wheels on the glider. The glider that we used for the initial flights was a Wedgetail 3 which is a 30%'er with preformed battens.

The bridle and equipment was quite easy to sort out and adjust up. All I did was refer to your newsletters for anything that I didn't quite understand.

The takeoff proceedure that we use is probably what you would call pop starting. The car takes off quickly and the pilot in the hang glider holds back till the pressure starts pulling him along. Two light steps and he is airborne. Taking off is as easy as taking off in smooth soaring conditions.

One mistake that everyone seems to make when first flying with the skyting system is over correction in turns or over correcting the yaw of the glider. After a couple of flights they (the pilots) settle down really well and the problems seem to disappear. Even with beginner rated pilots the over correction is only a minor concern.

We have flown in various winds from light to quite strong (25mph) even 45 degrees cross winds with successful results.

We are now using 1000 ft of rope and are looking at our local airport to tow from, with 4000 ft of rope.

Your skyting system appears to be a very easy and safe system of towing.

Dave McGill
Blenheim, New Zealand
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TOWING ILLEGAL IN NORWAY
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1983/11-10

Dear Donnell,

I've been reading everything about Skyting in Hang Gliding Magazine and Whole Air Magazine lately with great interest. It sounds like a lot safer and easier way to be towed than compared to the Bennett/Moyes equipment.

I'm sure most pilots in my area are going to be hooked on this sort of flying since we have lots of landing fields and lakes and less take-off possibilities. We also live by the coast.

I'd like to know if ther are things (secrets) around the Skyting system which are not mentioned in the article? Can you ship me two "three ring releases" and mounting details, length of bridles, etc.?

This year I have logged close to twenty hours in my Pro Star II, 160 sq. ft. I have never towed before, but always wanted to. I've been flying gliders for more than 7 years. I'm self taught, and that almost killed me a few times. Since towing is more dangerous, I'd like to eliminate danger as much as possible before I try it out. By now I have a hang IV rating and am a licensed instructor. Towing is still illegal in Norway, but it has got to be accepted now with this new equipment.

Many thanks in advance for your help.

Oddvar Lallhovd
Kristiansand S.
Norway
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1983/11-11

Dear Oddvar,

You can obtain three-ring releases (2 for US$25.00 plus shipping) from High Energy Sports, 2312 W. 2nd St., Santa Ana, CA 92703, U.S.A.

There are no "secrets" about skyting, but there are a large number of small details (not covered in Hang Gliding and Whole Air articles) which you should be aware of if you really want to be safe. I strongly suggest that you read all of the back issues of SKYTING which contain personal accounts of accidents, problems, mistakes, and solutions which different people have experienced. You are almost certainly going to repeat some of these mistakes if you are not aware of them, and repeating only one could cost more than the price of a set of back issues. The cost of two years of SKYTING (back issues through No. 23, March 1984) is US$20.00 plus $15.00 for foreign shipping.)

If you are trying to get towing legalized, you will have to be able to demonstrate to the authorities that it can be done safely, and you cannot afford to have an accident early in your own flying. It is important, therefore, that you take every conceivable precaution in your development.

Donnell
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