Kite Strings

Hook-In Signs, Gadgets And Electronic Alarms
by Harry Martin

THE HOOK-IN PROBLEM

What is it in our brains that allows us to run off launch ramps with full confidence to fly, but oblivious to making that safety link between body and flying machine? What human trait grants us the audacity to fling our bodies into the air like the mindless lemmings of the arctic without first checking our hang straps?

Maybe it's nature's way of getting rid of the less fit--the ones that survived childbirth thanks to modern medicine--or the ones saved by a society that enforces laws designed to protect people from themselves. Maybe our sport's collective consciousness is so diluted with ill-thinking, intellectually-deprived pilots that nature is now getting even with the technically advanced idiots who fail to hook in. I dunno. I suppose it's what I refer to as "Oafism," a disease of the mind, the soil of thing that happens when you push the wrong button on the vending machine to get a candy bar, and get a bag of stale peanuts instead. You saw the right button, you reached for the right button, and yet you pushed the wrong button. "What a jerk," you think to yourself, and put more money in the machine and try again.

In hang gliding you're lucky to get a second chance when you fail to hook in. We don't fly with air bags, seat belts or protective cushions to protect us against hard impacts. We can't. We wouldn't be able to pick up all the safety equipment we'd have to install on our foot-launched gliders. Our soft, fleshy bodies fair poorly against lichen-covered basalt, so we rely on our highly developed intellect to prevent such mishaps.

Unfortunately, that intellect has failed a few of us. I know some pilots in my club who have failed to hook in. They never dreamt it would happen to them; but despite their best efforts it happened, I believe this is one area of our sport that needs improvement. To help eliminate oafisms, we have some pretty ingenious gadgets and rituals that can make that critical safety check a sure thing every time.

I wish to explore some of those hook-in devices, touching on the pro's and cons of each of them, and then proceed with a description of my own personal electronic hook-in alarm. Keep in mind that these are all good ideas, and all could be used to prevent failures to hook in.

HOOK-IN SIGNS

The first item is the visual warning. It's usually located in the vicinity of the launch ramp if not trampled by a previous pilot or vandal.

Pro: The hook-in sign will remind you that the unseen force of gravity is about to be tested, with YOU being the subject of the next experiment, YOU will see this sign and think to yourself, "Am I hooked in?" and make that last visual check to verify that the carabiner is in fact locked into the hang strap. YOU will get a valuable hang check from your trusted companions, and just prior to launch, to prove to yourself that you are hooked in, YOU will lift your glider up so high that you can feel the hang straps.

Con: The lights are on but nobody's home. You see the sign so many times that your mind learns to blank it out. How many times do you read a sign until it is ignored? You didn't see that your carabiner wasn't hooked in; what makes you think you'll see a sign that your brain doesn't read? Your eyes will not believe what your hands have failed to do when it's too late to hook in.

Personal Opinion: Hook-in signs work. Cartoonist Bob Lafay, has painted some rather clever signs that catch my attention prior to launch, it seems that there is a new one posted every other time I visit the launch ramp. I can't help but think about safety after seeing one of his signs, I would suggest that each club produce several different and unique signs, and post them on a rotating basis so that frequent flyers can continue to defy gravity. My thanks to Bob Lafay for his efforts to save my skin.

GHASTLY GADGETS

Some pilots use add-on gadgets to "flag" them when they are not hooked in. There is one in particular that scares me. Jack Wathey wrote about a bungee and nylon cord device (see the October '91 issue, page 26) which I have seen in a previous issue of Hang Gliding. Another one by Henry Boessel (see the January '92 issue, page 51) is similar to Jack's, but appears to be a better design.

Pro: It's cheap and easy to use. No batteries required. Relies on elastic material and gravity. As long as you remember to hook into all three loops, you will not see the warning flag hanging down. As long as you are not blind, the device will do its job.

Con: You now have three loops in which to lock your carabiner. What do you think will happen if you just hook into that one thin nylon loop that pulls the bungee, and forget the primary and backup strap? (It can happen. After all, pilots fail to hook in without this gadget.) The design is no better than none at all. Too many straps and cords hanging down can result in added confusion for a new pilot who is suffering from input overload, the same input overload that almost got me on several occasions. I like the idea of a single hang strap myself, though I do use a backup. Suppose the flag does not hang down far enough because it is clinging to some other material? This device relies on the pilot to make sure it is set up prior to use, and needs a preflight check. Again, if you unhook for some reason and fail to hook in a second time because the flag got caught on something, you are in danger. And one more loop from which to unhook means one move hassle in an emergency.

Personal Opinion: The chances of hooking in improperly when using a bungee cord warning device may be greater than not using one at all. I would not want to hassle with more than one or two loops during hook-in. Never underestimate the power of a simple hang check. As Jack Wathey admitted, his instructor gave him a visual hang check that saved his bones and glider from possible destruction. Given the choice between Henry's and Jack's design, I'll take Henry's.

HIGH TECH ELECTRONIC HOOK-IN ALARMS

So, what other gadgets are there to warn of failure to hook in? Let's look at electronic devices. To my knowledge, there are presently two ideas festering in the background, my unpatented hook-in alarm and John Gray's patented hook-in alarm. The devices use a sensor to detect the carabiner, a level sensor to detect when the glider is straight and level for launch, and a rather loud buzzer or siren to alert the pilot that a failure to hook in has occurred upon picking up the glider.

Pro: The electronic hook-in alarm eliminates a third loop to pull away a visual flag. The carabiner sensor can be attached to the primary or backup hang strap and greatly simplify the hook-in procedure. No additional hookups, wires or gaudy accessories are needed to warn the pilot. A sufficiently loud buzzer will warn the pilot that he is about to launch without hooking in. Due to the unique sensor design, hooking and unhooking are no different than when not using the alarm. The level sensor prevents the alarm from sounding while setting up the glider, and since the alarm would only be active during launch, the battery should last a couple of years.

Con: It needs a battery. What if the battery dies the same day you forget to get a hang check? Suppose a switch breaks during a bad landing. Will it work the next time around? Will dirt and dust enter the mechanical parts and muck up the delicate electronic guts? How about false alarms? How long will you be willing to listen to an obnoxious alarm before you get fed up with the device, rip it off your glider and stomp it into the ground? Besides, the sensor, wire and little black box look kinda nerdy on a sleek gliding machine.

Personal Opinion: The electronic hook-in alarm works. I've seen John's design work, and my "final" design (at some point you have to shoot the engineer and get on with production) is on my glider and has been working for some time now. The electronic guts and switches can be made weather and shock proof. The battery can be replaced before it would ever fail (you fly with a battery in your vario, right?), and developing better preflight habits should minimize false alarms.

Quite frankly, I do not believe any of these devices, by themselves, will prevent failures to hook in. There will always be someone, somewhere who will just oaf out. But I believe the chances of making such a mistake can be greatly reduced.

All of the above devices, along with the tried-and-true hang check, will minimize the number of accidental failures to hook in. I know there are more pros and cons for each of the above, so where does that leave us? Hopefully, a majority of us will take advantage of some or all of these ideas for safety, and reaffirm good preflight habits.

A PERSONAL ELECTRONIC HOOK-IN ALARM

Of all the great articles that appear in Hang Gliding magazine, I find Doug Hildreth's accident reports the most illuminating. We can learn from the mistakes of others, and the recent significant increase in the number of pilots who fail to hook in greatly disturbs me. I can't help but wonder when it may happen to me.

Knowing my own limitations, and realizing that I could suffer a severe oafism, I decided to design my own hook-in alarm. In 1988 I built a working prototype and tried it out on a pilot friend to see what would happen. It had an obvious design flaw and was laughed out of existence.

So I tried all sorts of designs in the privacy of my own harness when no one was looking. I played with magnetic sensors, infrared optical sensors, spring-loaded switches, bungee cords and other crazy schemes. The most difficult thing about the whole project was figuring out how to install an indestructible, nice looking, inexpensive sensor in a soft, mushy hang strap. I wanted something that would detect the fact that you were hooked in through the simple act of hooking in, without the need to pull on a third loop or plug in a connector. The sensor needed to be easily installed on any glider without hassle, and it had to work with any arrangement of the carabiner. The hang strap offers no support for a rigid sensor that must be in close proximity to the device that it is trying to sense. The carabiner flops around and changes position in the strap. This problem was to be a thorn for quite some time, I finally worked out a design which I would like to share with everyone. I can only hope that this idea will spur people to either build the device, or demand that glider manufacturers look into installing such a device as an option on your next new glider.

So what is the great solution? It's simple: the carabiner is metal and therefore conducts electricity. It is a very simple matter to install two very small metal plates inside your backup hang strap. The two metal plates are connected to wires that go to an alarm circuit. As soon as you hook in, the carabiner makes contact across the plates and deactivates the alarm. Thus, your carabiner acts as a switch to close a sensor circuit.

Since the carabiner is the switch, there is nothing to wear out, get dirty or replace except for the carabiner itself. But, as with any piece of equipment, it is only as good as the person who uses it. Use it correctly and it could save your life. It only has to work once to prove a point, as did the first pilot who was saved by a backup parachute in the 70's. I hope to hear someday that a pilot was saved by either John's design or mine.

CONSTRUCTION AND THEORY OF OPERATION

As mentioned, the carabiner is the switch for the sensor in the hang strap. That leaves the alarm circuit. My alarm circuit utilizes two timers and the actual ear-piercing buzzer. One timer delays turning on the alarm for a couple of seconds to help reduce the number of false alarms. The other timer delays turning off the alarm so that after a couple of minutes of a 78-decibel earache it will shut down to save the battery. I figure that if you don't take action to hook in during those first two minutes, you're either deaf or nowhere near the glider. I have included the basic schematic for the overall circuit except for the actual alarm guts. Ninety-nine percent of the parts can be found at Radio Shack. Almost any simple electronic alarm can be used, and it does not have to include delays. Removing the delay circuitry greatly simplifies its construction, but this was a feature that I wanted in the overall design.

The buzzer is a piezo electric transducer that screams as loud as a crying infant who wants attention. It was tested to be quite obnoxious from 12 volts DC all the way down to three volts DC. I used CMOS parts to get a wider operating voltage range. A nine-volt lithium battery should last longer than the hang straps on my glider.

When the glider is tail down for setup, breakdown, or standby prior to flight, a mercury (Hg) bulb tilt switch turns all power off and resets both timers. As soon as the glider is lifted and is level for flight, the mercury tilts to the other side of the bulb, powers up the circuit, and starts the timers. If the carabiner contacts the sensor both timers are reset, and the alarm is disabled until you unhook. If you unhook while the alarm is active, both timers restart and will time out all over again. Thus, in my design, much attention was given to preserving battery life, and making sure that the timers would always restart no matter when or how often you unhook or hook in.

The carabiner circuit is sensitive enough to detect a finger across the contact plates, so that even the dirtiest carabiner (steel or aluminum) will be detected. The contact plates that mount in the hang strap were constructed from pieces of non-anodized aluminum. Stainless steel would be better, but aluminum is easier to work with, with limited hand tools. The plates where mounted (are you ready for this?) to the wood pieces of a clothes pin. Yep, I discovered that the spring between those two pieces of wood provided the perfect tension to keep the plates against the carabiner. I experimented with bungee cord material, but discovered that with time the bungee weakens and loses its grip (the stuff just gets tired). The plates were then sewn into the backup strap using just a few stitches. The sensor is easily inspected for damage and can be moved to a new strap should the backup ever need replacing. With just a little care, I expect the sensor to last the rest of my natural flying life. I chose to put the plates inside the backup to save wear and tear on the sensor. Should I fail to hook into my primary strap, at the very least, I would be hooked into my backup.

The last thing I added to the design was an arming pin. The arming pin is attached to the glider cover bag with a long cord. As long as the pin remains in the alarm it is disarmed and off, to save the battery no matter what position the glider is in. When the cover bag comes off, the pin pulls out to arm the circuit. Thus, the pilot does not need to remember to turn on the alarm.

As an alternative, a flag could be attached to the pin instead of the cover bag. The pilot could then remove the pin prior to flight, eliminating possible false alarms while ground handling the glider. If the pilot forgets to put the pin back in after putting the glider away, the second timer will automatically shut down the alarm to save the battery.

The arming pin contains a small bar magnet that activates a normally open magnetic reed switch. When the pin is in, the reed switch opens to kill battery power, When the pin is pulled, the switch closes to turn on battery power. A reed switch was used so that it can be sealed from the weather. Everything was neatly tucked inside the plastic housing that I constructed from PVC end caps. The pin can be inserted from either side into a plastic sleeve. Thus, I have a circuit which is fully protected from moisture and dust.

All parts are mounted with epoxy adhesives and a little super glue here and there. The Hg bulb switch is sandwiched between layers of foam tape to provide shock mounting and the plastic housing was cut and shaped so that it will fit flush with the keel. A piece of foam rubber seals the battery compartment from the elements and the whole thing is held in place with some of our favorite material, velcro.

The photographs of the installed system show that it requires very little room to install. As a matter of fact, I have another design that slips right into a downtube, so if it weren't for the sensor wire you wouldn't even know it was on the glider. Another design could be easily installed into the hollow keel of any glider, since control bar configurations differ.

THE FUTURE

This is where I put in a pitch for glider manufacturers to consider designing keels to house such a device. How much trouble would it be to incorporate a small compartment to accommodate a battery and alarm? The battery could be slipped into the keel near an endcap, with the rest of the circuit closer to the kingpost. The whole circuit is inexpensive enough to be considered disposable. It could be installed on all gliders as a feature, then it would be up to the pilot to decide whether or not to use it.

The most common reaction from seasoned pilots is: "That's a great idea for students." Old salty flying dogs may not go for this, so there may not be a market for an electronic hook-in alarm. But I remember when I bought a parachute in 1978 when no one wanted them. A week later I was getting calls from my flying buddies begging me to let them borrow it. Their plea was: "I'm going to do some heavy duty flying this weekend, can I please borrow your parachute?" What kind of flying were they doing prior to that weekend, sissy flying? I told them to get lost as I hugged by new parachute. So now I've got my hook-in alarm and a parachute that I've never had to use.

Will anyone buy it? Does anyone want it? It remains to be seen. The whole argument for having one is easily shot down by the fact that hang checks cost nothing.

It is my opinion that hook-in signs, stringy gadgets, alarms and hang checks will all help to prevent failures to hook in. I hope my electronic solution encourages more pilots to experiment with such devices. The hook-in alarm is not meant to replace the hang check, but only to act as a backup should other safety checks fail. Should I ever be the last pilot off the mountain with no launch assist for a hang check, I'm betting that it will prevent a failure to hook in. I would encourage glider manufacturers to consider installing such a device as an option. Maybe someday a doctor will invent a pill to cure oafism, and we will never read about failures to hook in again.

Inquiries and requests for further information about this alarm can be addressed to: Harry Martin, 706 Tudor Cir., Thousand Oaks, CA 91360.-Ed.
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Close-up of sensor plates. Note that plates are tacked inside of hang strap with thread,
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Alarm with gasket--arming pin in place.
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ABOVE: Left--glider on ground prior to setup. Velcro keeps alarm in place. Right--complete setup, demonstrating pulling of arming pin as cover bag is removed.
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Hook-In Signs, Gadgets And Electronic Alarms
by Harry Martin

THE HOOK-IN PROBLEM

What is it in our brains that allows us to run off launch ramps with full confidence to fly, but oblivious to making that safety link between body and flying machine? What human trait grants us the audacity to fling our bodies into the air like the mindless lemmings of the arctic without first checking our hang straps?

Maybe it's nature's way of getting rid of the less fit--the ones that survived childbirth thanks to modern medicine--or the ones saved by a society that enforces laws designed to protect people from themselves. Maybe our sport's collective consciousness is so diluted with ill-thinking, intellectually-deprived pilots that nature is now getting even with the technically advanced idiots who fail to hook in.

I dunno.

I suppose it's what I refer to as "Oafism," a disease of the mind, the soil of thing that happens when you push the wrong button on the vending machine to get a candy bar, and get a bag of stale peanuts instead. You saw the right button, you reached for the right button, and yet you pushed the wrong button. "What a jerk," you think to yourself, and put more money in the machine and try again.

In hang gliding you're lucky to get a second chance when you fail to hook in.

We don't fly with air bags, seat belts or protective cushions to protect us against hard impacts.

We can't. We wouldn't be able to pick up all the safety equipment we'd have to install on our foot-launched gliders.

Our soft, fleshy bodies fair poorly against lichen-covered basalt, so we rely on our highly developed intellect to prevent such mishaps.

The Press - 2006/03/15

The Civil Aviation Authority (CAA) is urgently pushing for new hang-gliding industry standards after learning a hang-gliding pilot who suffered serious injuries in a crash three weeks ago had not clipped himself on to the glider.

Extreme Air tandem gliding pilot James (Jim) Rooney safely clipped his passenger into the glider before departing from the Coronet Peak launch site, near Queenstown, CAA sports and recreation manager Rex Kenny said yesterday.

However, he took off without attaching himself.

In a video, he was seen to hold on to the glider for about fifty meters before hitting power lines.

Rooney and the passenger fell about fifteen meters to the ground.

Jim Rooney - 2006/09/24 21:19:29 UTC

Ok, this thread's a million miles long already (and mostly my fault at that), so I'm not going to feel bad about making it a tad longer.

A couple things to chew on here...

There isn't one sure-fire answer.
If there was, we'd all be doing it already. This thread I think makes this obvious... every single thing people have put forth as "the way", someone else has show how it can fail. Every single one. Argue about the details, but every single one fails.

Here's the real trick of it in my book (especially with new technology, but it applies to methods too)...
Whatever you change only works on that glider/site/whatever.
What happens when you're off flying somewhere else or flying someone else's gear?

Someone suggested putting a red flag on the nose of the glider that gets removed after the hang check... this way, if you haven't hooked in, it's really obvious. Say this works for you and you get used to it. Then you borrow a glider or fly a different site on a rented glider. In your world, no red streamer means "good to go".

Take Aussied vs clipin if you like... what happens when you're at a site that you can't use the aussie method with? (I can name you some cliff launches that you can't if you care). Now you're used to the security of the aussie method, and it's not there. You might say that the fear will help you, but your instincts will say otherwise (the fear is highlevel thought, and highlevel thought is the first thing that gets tossed out of your brain.. else we'd never launch unhooked in the first place).

Argue if you will about the examples (whatever), the trick of it isn't the method to me, it's how using new things doesn't work (and actually causes problems) in strange ways (like when going back to "normal" flying after getting used to the new method/device).

Enough about what doesn't work though... what does?
Since we don't have a plug that only fits one way, we fall on lesser methods, but some are better than others...

In particular... Third Party Verification.
You won't save you, but your friends might.
Not always, but they're more reliable than you.
Why do you think that airline checklists (yes our lovely checklists) are check-verified by pilot AND copilot?

That's all I got for ya.
The other topics have been beat to death here.
If there was an answer, we'd all already be doing it.

Unfortunately, that intellect has failed a few of us.

I know some pilots in my club who have failed to hook in.

In hang gliding you're lucky to get a second chance when you fail to hook in.

They never dreamt it would happen to them;

...but despite their best efforts it happened...

I believe this is one area of our sport that needs improvement.

To help eliminate oafisms, we have some pretty ingenious gadgets and rituals that can make that critical safety check a sure thing every time.

I wish to explore some of those hook-in devices...

...touching on the pro's and cons of each of them...

...and then proceed with a description of my own personal electronic hook-in alarm. Keep in mind that these are all good ideas...

...and all could be used to prevent failures to hook in.

Hook-In Signs, Gadgets And Electronic Alarms
by Harry Martin

HOOK-IN SIGNS

The first item is the visual warning. It's usually located in the vicinity of the launch ramp if not trampled by a previous pilot or vandal.

Pro: The hook-in sign will remind you that the unseen force of gravity...

...is about to be tested, with YOU being the subject of the next experiment, YOU will see this sign and think to yourself, "Am I hooked in?" and make that last visual check to verify that the carabiner is in fact locked into the hang strap.

YOU will get a valuable hang check from your trusted companions...

...and just prior to launch, to prove to yourself that you are hooked in, YOU will lift your glider up so high that you can feel the hang straps.

Con: The lights are on but nobody's home. You see the sign so many times...

...that your mind learns to blank it out. How many times do you read a sign until it is ignored?

You didn't see that your carabiner wasn't hooked in; what makes you think you'll see a sign that your brain doesn't read?

Your eyes will not believe what your hands have failed to do when it's too late to hook in.

Personal Opinion: Hook-in signs work.

Cartoonist Bob Lafay, has painted some rather clever signs that catch my attention prior to launch, it seems that there is a new one posted every other time I visit the launch ramp.

I can't help but think about safety after seeing one of his signs...

I would suggest that each club produce several different and unique signs, and post them on a rotating basis so that frequent flyers can continue to defy gravity.

My thanks to Bob Lafay for his efforts to save my skin.

Hook-In Signs, Gadgets And Electronic Alarms
by Harry Martin

GHASTLY GADGETS

Some pilots use add-on gadgets to "flag" them when they are not hooked in.

Alan Deikman - 2012/07/17 17:57:38 UTC

I designed a mechanism to prevent FTHI which I think would be pretty effective, probably with the same failure rate as the glider itself. I will never implement it, and if I applied for a patent it would be for the express purpose of stopping anyone else from implementing it.

If you don't understand why then I don't think you understand the central issue on this topic.

There is one in particular that scares me.

Jack Wathey wrote about a bungee and nylon cord device (see the October '91 issue, page 26) which I have seen in a previous issue of Hang Gliding. Another one by Henry Boessel (see the January '92 issue, page 51) is similar to Jack's, but appears to be a better design.

Pro: It's cheap and easy to use. No batteries required. Relies on elastic material and gravity. As long as you remember to hook into all three loops...

...you will not see the warning flag hanging down. As long as you are not blind, the device will do its job.

Con: You now have three loops in which to lock your carabiner.

What do you think will happen if you just hook into that one thin nylon loop that pulls the bungee, and forget the primary and backup strap?

(It can happen. After all, pilots fail to hook in without this gadget.)

The design is no better than none at all.

Too many straps and cords hanging down can result in added confusion for a new pilot who is suffering from input overload, the same input overload that almost got me on several occasions.

I like the idea of a single hang strap myself, though I do use a backup.

Suppose the flag does not hang down far enough because it is clinging to some other material?

This device relies on the pilot to make sure it is set up prior to use, and needs a preflight check. Again, if you unhook for some reason and fail to hook in a second time because the flag got caught on something, you are in danger. And one more loop from which to unhook means one move hassle in an emergency.

Personal Opinion: The chances of hooking in improperly when using a bungee cord warning device may be greater than not using one at all. I would not want to hassle with more than one or two loops during hook-in.

Never underestimate the power of a simple hang check.

As Jack Wathey admitted, his instructor gave him a visual hang check that saved his bones and glider from possible destruction.

Given the choice between Henry's and Jack's design, I'll take Henry's.

Hook-In Signs, Gadgets And Electronic Alarms
by Harry Martin

HIGH TECH ELECTRONIC HOOK-IN ALARMS

So, what other gadgets are there to warn of failure to hook in?

Let's look at electronic devices.

To my knowledge, there are presently two ideas festering in the background, my unpatented hook-in alarm and John Gray's patented hook-in alarm. The devices use a sensor to detect the carabiner, a level sensor to detect when the glider is straight and level for launch, and a rather loud buzzer or siren to alert the pilot that a failure to hook in has occurred upon picking up the glider.

Pro: The electronic hook-in alarm eliminates a third loop to pull away a visual flag.

The carabiner sensor can be attached to the primary or backup hang strap...

...and greatly simplify the hook-in procedure. No additional hookups, wires or gaudy accessories are needed to warn the pilot.

A sufficiently loud buzzer will warn the pilot that he is about to launch without hooking in.

Due to the unique sensor design, hooking and unhooking are no different than when not using the alarm. The level sensor prevents the alarm from sounding while setting up the glider, and since the alarm would only be active during launch, the battery should last a couple of years.

Con: It needs a battery. What if the battery dies the same day you forget to get a hang check?

Suppose a switch breaks during a bad landing. Will it work the next time around? Will dirt and dust enter the mechanical parts and muck up the delicate electronic guts?

How about false alarms? How long will you be willing to listen to an obnoxious alarm before you get fed up with the device, rip it off your glider and stomp it into the ground?

Besides, the sensor, wire and little black box look kinda nerdy on a sleek gliding machine.

Personal Opinion: The electronic hook-in alarm works.

I've seen John's design work, and my "final" design (at some point you have to shoot the engineer and get on with production)...

...is on my glider and has been working for some time now.

The electronic guts and switches can be made weather and shock proof.

The battery can be replaced before it would ever fail (you fly with a battery in your vario, right?)...

...and developing better preflight habits should minimize false alarms.

Quite frankly, I do not believe any of these devices, by themselves, will prevent failures to hook in. There will always be someone, somewhere who will just oaf out. But I believe the chances of making such a mistake can be greatly reduced.

With each flight, demonstrates a method of establishing that the pilot is hooked in just prior to launch.

All of the above devices, along with the tried-and-true hang check...

...will minimize the number of accidental failures to hook in.

I know there are more pros...

...and cons for each of the above, so where does that leave us?

Hopefully, a majority of us will take advantage of some or all of these ideas for safety...

...and reaffirm good preflight habits.

Hook-In Signs, Gadgets And Electronic Alarms
by Harry Martin

A PERSONAL ELECTRONIC HOOK-IN ALARM

Of all the great articles that appear in Hang Gliding magazine, I find Doug Hildreth's accident reports the most illuminating.

We can learn from the mistakes of others, and the recent significant increase in the number of pilots who fail to hook in greatly disturbs me.

I can't help but wonder when it may happen to me.

Alan Deikman - 2014/09/23 19:47:06 UTC

For my part I will just refer you to the classic Tad Eareckson essay which I call "the gun is always loaded" which is a bit overworked but probably all you will ever need to read regarding FTHI. A lot of people will find it gores their particular sacred Ox, but I have never seen anyone point out a flaw in his logic.

Knowing my own limitations, and realizing that I could suffer a severe oafism...

I decided to design my own hook-in alarm.

In 1988 I built a working prototype and tried it out on a pilot friend to see what would happen. It had an obvious design flaw and was laughed out of existence.

So I tried all sorts of designs in the privacy of my own harness when no one was looking. I played with magnetic sensors, infrared optical sensors, spring-loaded switches, bungee cords and other crazy schemes.

The most difficult thing about the whole project was figuring out how to install an indestructible, nice looking, inexpensive sensor in a soft, mushy hang strap. I wanted something that would detect the fact that you were hooked in through the simple act of hooking in, without the need to pull on a third loop or plug in a connector. The sensor needed to be easily installed on any glider without hassle...

...and it had to work with any arrangement of the carabiner.

The hang strap offers no support for a rigid sensor that must be in close proximity to the device that it is trying to sense. The carabiner flops around and changes position in the strap. This problem was to be a thorn for quite some time, I finally worked out a design which I would like to share with everyone. I can only hope that this idea will spur people to either build the device, or demand that glider manufacturers look into installing such a device as an option on your next new glider.

So what is the great solution? It's simple: the carabiner is metal and therefore conducts electricity.

It is a very simple matter to install two very small metal plates inside your backup hang strap. The two metal plates are connected to wires that go to an alarm circuit. As soon as you hook in, the carabiner makes contact across the plates and deactivates the alarm. Thus, your carabiner acts as a switch to close a sensor circuit.

Since the carabiner is the switch, there is nothing to wear out, get dirty or replace except for the carabiner itself. But, as with any piece of equipment, it is only as good as the person who uses it.

Use it correctly and it could save your life.

It only has to work once to prove a point...

...as did the first pilot who was saved by a backup parachute in the 70's.

I hope to hear someday that a pilot was saved by either John's design or mine.

Hook-In Signs, Gadgets And Electronic Alarms
by Harry Martin

CONSTRUCTION AND THEORY OF OPERATION

As mentioned, the carabiner is the switch for the sensor in the hang strap. That leaves the alarm circuit. My alarm circuit utilizes two timers and the actual ear-piercing buzzer. One timer delays turning on the alarm for a couple of seconds to help reduce the number of false alarms. The other timer delays turning off the alarm so that after a couple of minutes of a 78-decibel earache it will shut down to save the battery. I figure that if you don't take action to hook in during those first two minutes, you're either deaf or nowhere near the glider. I have included the basic schematic for the overall circuit except for the actual alarm guts. Ninety-nine percent of the parts can be found at Radio Shack. Almost any simple electronic alarm can be used, and it does not have to include delays. Removing the delay circuitry greatly simplifies its construction, but this was a feature that I wanted in the overall design.

The buzzer is a piezo electric transducer that screams as loud as a crying infant who wants attention. It was tested to be quite obnoxious from 12 volts DC all the way down to three volts DC. I used CMOS parts to get a wider operating voltage range. A nine-volt lithium battery should last longer than the hang straps on my glider.

When the glider is tail down for setup, breakdown, or standby prior to flight, a mercury (Hg) bulb tilt switch turns all power off and resets both timers. As soon as the glider is lifted and is level for flight, the mercury tilts to the other side of the bulb, powers up the circuit, and starts the timers. If the carabiner contacts the sensor both timers are reset, and the alarm is disabled until you unhook. If you unhook while the alarm is active, both timers restart and will time out all over again. Thus, in my design, much attention was given to preserving battery life, and making sure that the timers would always restart no matter when or how often you unhook or hook in.

The carabiner circuit is sensitive enough to detect a finger across the contact plates, so that even the dirtiest carabiner (steel or aluminum) will be detected. The contact plates that mount in the hang strap were constructed from pieces of non-anodized aluminum. Stainless steel would be better, but aluminum is easier to work with, with limited hand tools. The plates where mounted (are you ready for this?) to the wood pieces of a clothes pin. Yep, I discovered that the spring between those two pieces of wood provided the perfect tension to keep the plates against the carabiner. I experimented with bungee cord material, but discovered that with time the bungee weakens and loses its grip (the stuff just gets tired). The plates were then sewn into the backup strap using just a few stitches. The sensor is easily inspected for damage and can be moved to a new strap should the backup ever need replacing. With just a little care, I expect the sensor to last the rest of my natural flying life. I chose to put the plates inside the backup to save wear and tear on the sensor. Should I fail to hook into my primary strap, at the very least, I would be hooked into my backup.

The last thing I added to the design was an arming pin. The arming pin is attached to the glider cover bag with a long cord. As long as the pin remains in the alarm it is disarmed and off, to save the battery no matter what position the glider is in. When the cover bag comes off, the pin pulls out to arm the circuit. Thus, the pilot does not need to remember to turn on the alarm.

As an alternative, a flag could be attached to the pin instead of the cover bag. The pilot could then remove the pin prior to flight, eliminating possible false alarms while ground handling the glider. If the pilot forgets to put the pin back in after putting the glider away, the second timer will automatically shut down the alarm to save the battery.

The arming pin contains a small bar magnet that activates a normally open magnetic reed switch. When the pin is in, the reed switch opens to kill battery power, When the pin is pulled, the switch closes to turn on battery power. A reed switch was used so that it can be sealed from the weather. Everything was neatly tucked inside the plastic housing that I constructed from PVC end caps. The pin can be inserted from either side into a plastic sleeve. Thus, I have a circuit which is fully protected from moisture and dust.

All parts are mounted with epoxy adhesives and a little super glue here and there. The Hg bulb switch is sandwiched between layers of foam tape to provide shock mounting and the plastic housing was cut and shaped so that it will fit flush with the keel. A piece of foam rubber seals the battery compartment from the elements and the whole thing is held in place with some of our favorite material, velcro.

The photographs of the installed system show that it requires very little room to install. As a matter of fact, I have another design that slips right into a downtube, so if it weren't for the sensor wire you wouldn't even know it was on the glider. Another design could be easily installed into the hollow keel of any glider, since control bar configurations differ.

...and just prior to launch, to prove to yourself that you are hooked in, YOU will lift your glider up so high that you can feel the hang straps.

Hook-In Signs, Gadgets And Electronic Alarms
by Harry Martin

THE FUTURE

This is where I put in a pitch for glider manufacturers to consider designing keels to house such a device.

How much trouble would it be to incorporate a small compartment to accommodate a battery and alarm?

The battery could be slipped into the keel near an endcap, with the rest of the circuit closer to the kingpost. The whole circuit is inexpensive enough to be considered disposable. It could be installed on all gliders as a feature, then it would be up to the pilot to decide whether or not to use it.

The most common reaction from seasoned pilots is: "That's a great idea for students."

Old salty flying dogs may not go for this, so there may not be a market for an electronic hook-in alarm.

But I remember when I bought a parachute in 1978 when no one wanted them. A week later I was getting calls from my flying buddies begging me to let them borrow it. Their plea was: "I'm going to do some heavy duty flying this weekend, can I please borrow your parachute?" What kind of flying were they doing prior to that weekend, sissy flying? I told them to get lost as I hugged by new parachute. So now I've got my hook-in alarm and a parachute that I've never had to use.

Will anyone buy it?

Does anyone want it? It remains to be seen.

The whole argument for having one is easily shot down by the fact that hang checks cost nothing.

It is my opinion that hook-in signs, stringy gadgets, alarms and hang checks will all help to prevent failures to hook in.

I hope my electronic solution encourages more pilots to experiment with such devices.

The hook-in alarm is not meant to replace the hang check...

...but only to act as a backup should other safety checks fail.

Should I ever be the last pilot off the mountain with no launch assist for a hang check, I'm betting that it will prevent a failure to hook in.

I would encourage glider manufacturers to consider installing such a device as an option.

Maybe someday a doctor will invent a pill to cure oafism, and we will never read about failures to hook in again.

Harry Martin - Caspar, Wyoming - 15705 - Pilot

Holly Korzilius - 2005/10/01 18:19:55 UTC

Incident at 2005 Team Challenge

I don't have many details at this point, but I just got a call from Scott Wilkinson. Bill Priday launched from Whitwell without hooking in. Scott indicated there was about a hundred foot drop off from launch. Bill's status is unknown at this time. Please pray for him!

I will provide updates as I get them from Scott.

Holly Korzilius - 2005/10/01 18:38:40 UTC

Status Update

Scott just informed me that Bill didn't make it. He died. The only other information I have is that no CHGPA or Blue Sky pilots were part of Bill's wire crew.

I don't know what else to say. I'm sitting here weeping for Bill. He was such a wonderful guy. So full of life and fun loving.

Scott Wilkinson - 2005/10/02 15:09:27 UTC

Team Challenge, Day Two...

There was a long, emotional pilots' meeting this morning by the ramp at Henson's.

Dean Funk, the meet organizer, has been devastated by Bill's death as much as anyone, having seen other deaths in the sport, and having actually left the sport, sold all his gear, and only recently decided to start flying again.

One thing is painfully obvious to everyone here: there was no official structure at launch yesterday. No designated Launch Director, no designated Safety Director.

With each flight, demonstrates a method of establishing that the pilot is hooked in just prior to launch.

We all know there should have been. And, of course, there will be from now on.

With each flight, demonstrates a method of establishing that the pilot is hooked in just prior to launch.

Some might blame the Team Challenge organizers for that oversight, but of course blaming anyone for Bill's death would be useless.

There were many contributing factors, not least of which was Bill's own carelessness and gung-ho attitude.

Dean asked if anyone wanted to say anything about Bill.

After an awkward moment of silence, I stepped up and tried my best to communicate the essence of Bill---his love and dedication to the sport, his big future plans, his warmth, and his eternal optimism.

It was incredibly hard, and I got choked up while talking. Thankfully, others stepped forward to offer their memories of Bill as well.

Finally, there was a long moment of silence in Bill's memory.

It was decided that the meet will go on today.

Everyone felt, as Dennis Pagen eloquently put it, that flying for all of us is an affirmation of life, and that flying is how best to commemorate Bill and move past his death. Conditions look good for another Whitwell day, with clear skies and E-SE winds.

Last night I was wanting to just pack up and leave. I still felt that way when I woke this morning...but after more reflection, more conversations with fellow pilots, and after our meeting I've decided to stay. I want to fly, as do others in our group...but today's still too soon. So Daniel, Linda, Rance, and myself are not flying today. We'll just relax, maybe watch some launches from Whitwell, and continue healing. Tomorrow is a new day, and we all want to get back in the air. We've got all week, and we plan to fly at our own pace...and not get caught up in any pressures---perceived or real---

...of competing for miles. (We may just end up free flying near the primary LZ all week, which suits us fine.)

Hank is flying today, and Bruce may fly (he's going to launch with gear, and will decide then). I'm happy they're flying, and hope they go high and far!

Meanwhile, all Bill's gear has been packed up and stowed in his truck, where it will remain until we drive it back to Richmond.

It's still enormously difficult to comprehend Bill's loss, but we're determined to carry on, be safer, more vigilant, follow our preflight routines even more vigilantly, and have fun---because that's what Bill would have wanted.

Scott Wilkinson - 2005/10/04 13:03:47 UTC

Tuesday morning...

Daniel, Linda and I all left yesterday, and are back in Richmond now after a long drive home. I wanted to fly in Tennessee, and hoped after a day of reflection and the passage of time I'd be in a better frame of mind. It never happened. Night before last, I awoke in my hammock in the middle of the night, and in the dark silence could only think of Bill. His fatal launch just kept rolling over and over in my head like a cursed video.

Daniel thought he might be able to fly too, but like me, he realized it was impossible. Rance, Bruce, Hank and Karma are still there. I hope they all flew high and far yesterday!

As I pondered whether to stay and fly, I never doubted my ability to launch and land safely. For me though, flying is every bit as much mental as physical (probably more so). My mental state is everything. Perhaps if I'd had years of experience under my belt (like many other pilots at the Team Challenge), I'd have been better able to put Bill's death behind me and simply enjoy being in the air again. But with my limited experience, I couldn't do it.

When I got into this sport, I made a promise to myself that I'd never fly unless I was feeling happy, optimistic, confident, physically fit, and completely comfortable.

Anything less, and I pack it up for the day. I doubt I would have felt any better had I stayed in Tennessee a few more days. There were still too many painful reverberations there.

I'm certain had there not been an accident, we would all have flown the entire week and had a great time. But it wasn't meant to be.

We arrived around 11pm last night at the home of Nick and Sandi Martina---two of Bill's best friends and neighbors. Tex Forrest was there too.

It was an emotional homecoming, as we all shared tears and hugs. Then we sat and talked about the accident...

...talked about Bill, and just decompressed. There were more tears during quiet moments, and also laughter remembering some of Bill's crazier moments.

Daniel, Linda and I are driving up to Blue Sky flight park this morning to see Steve and to drop off Bill's Sport 2.

With each flight, demonstrates a method of establishing that the pilot is hooked in just prior to launch.

The glider is in good shape---no tears in the sail, no noticeable breaks or bends in the airframe. Lots of scuffs on the leading edge, tangled VG lines, but nothing Steve couldn't easily fix.

(As I mentioned earlier, gliders don't land hard with nobody in them.)

There is a memorial service tentatively planned for this Saturday in Richmond. We should get confirmation sometime today. I don't know the family's wishes regarding how many people they'd mind coming (in case anyone wishes to attend), but I'll post information as soon as it's available.

Everyone felt, as Dennis Pagen eloquently put it, that flying for all of us is an affirmation of life, and that flying is how best to commemorate Bill and move past his death.