http://www.hanggliding.org/viewtopic.php?t=17603
Some [maybe old] thoughts about Failure to Hook In
fakeDecoy - 2010/06/09 21:44:37 UTC
Fort Funston
I'd just be compulsive about it like FPeel. If I'm approaching launch, I stop at launch and the last thing I do before considering whether to launch is to check several things without assistance, the last being the carabiner. If I do anything else before launching, or a couple minutes pass, I do it again. We don't need more gadgets or indicators. Just nail down a procedure.
Yeah...
With each flight, demonstrates a method of establishing that the pilot is hooked in before considering whether to launch or a couple of minutes prior to actually doing it.
Bob Kuczewski - 2010/06/09 21:49:53 UTC
Despite my previous design, that's what I actually do.
But new ideas come from new perspectives. If you have the energy to do something, then give it a try before you become old and set in your ways as most of us have.
Yeah, the LAST thing we wanna do...
George Whitehill - 1981/05
The point I'm trying to make is that every pilot should make a SECOND check to be very certain of this integral part of every flight. In many flying situations a hang check is performed and then is followed by a time interval prior to actual launch. In this time interval the pilot may unconsciously unhook to adjust or check something and then forget to hook in again. This has happened many times!
If, just before committing to a launch, a second check is done EVERY TIME and this is made a HABIT, this tragic mistake could be eliminated. Habit is the key word here. This practice MUST be subconscious on the part of the pilot. As we know, there are many things on the pilot's mind before launch. Especially in a competition or if conditions are radical the flyer may be thinking about so many other things that something as simple as remembering to hook in is forgotten. Relying on memory won't work as well as a deeply ingrained subconscious habit.
In the new USHGA rating system, for each flight of each task "the pilot must demonstrate a method of establishing that he/she is hooked in, just prior to launch." The purpose here is obvious.
Rob Kells - 2005/12
Always lift the glider vertically and feel the tug on the leg straps when the harness mains go tight, just before you start your launch run. I always use this test.
My partners (Steve Pearson and Mike Meier) and I have over 25,000 hang glider flights and have managed (so far) to have hooked in every time.
...is become set in our ways. Or old.
Steven Sims - 2010/06/09 22:42:26 UTC
Yes Bob, fresh H2 and still don't know how much I don't know.
Two ratings and the most critical requirement for both of them totally ignored. Where'd you say you got your training?
I'm glad to know I'm not the only mad scientist here, but now I guess I'm going to have to work up some numbers too, instead of just daydreaming about it.
The magnet / Hall effect sensor system does have advantage in that you wouldn't have to make any connections. The presence of the magnet on the 'biner will change the sensor's voltage and the microcontroller will read this voltage and light the LEDs accordingly. I think this would be a reliable system because (with a little calibration and error detection code in the microcontroller) a short in the sensor circuit would not lead to a false positive, but certainly that would need to be tested. I can't think of anything I pilot is likely to have near the carabiner that could create a false magnetic field...maybe if their iPod earbuds got tangled up in there somehow, LOL.
I thought separate green = 'go' and red = 'no-go' LEDs would be better, but you bring up a good point if switching gliders, or even if the system fails outright. I might have trained myself to just look to make sure there was no red light, but if I am instead accustomed to looking for only a green light, and now do not see it, I do think I'd fall back to a lift and tug or something at that point.
Yeah. That WOULD be a good Plan B. If you remember to do it. Or feel like doing it. Or something at that point.
I don't yet know how strong the magnet must be, how well the sensor will detect the magnetic field carried by the carabiner, nor how much current the sensor would flow. The microcontroller could switch the sensor on n times per second with some short duty cycle to conserve the battery, though. A small solar cell could be an option too, and then maybe it could be an always on system until the microcontroller sees no voltage from the solar cell for 10 minutes (because it is in the glider bag), so it turns itself off like a calculator.
Microcontroller would be a low power PIC of some flavor and is $3-$5, Hall effect sensor is $5, LEDs, tiny rare earth magnet, wiring, etc., a few more $. Not sure what the battery and/or solar would cost yet, as that depends on the power requirements.
Has anyone every built a prototype hook-in sensor system that you know of? I'm sure there are a lot of practical problems that would have to be solved, like survival of the wiring among all the flexing during flight and transport, whack impact forces, etc.
Bob Kuczewski - 2010/06/09 22:54:19 UTC
I haven't heard of anything, but let me know if you build something yourself. You can put me on the list of beta testers!!
I've programmed PICs before (back in the 90's) and even then, I was able to make one that ran 8 pretty bright LEDs for a long time with just a few watch batteries. The PIC is the way to go because you can program all kinds of features and they're very cheap. I started with the "burn once" variety, but moved over to the flash versions toward the end of my project (that shows how long ago it was). It's funny how much we've progressed since then ("pardon me while I reflash my hook in sensor from my cell phone").
Keep thinking my friend, but please be very very careful. I don't ever want to read that you failed to hook in because you were relying on a technology that failed you.
Don't worry, Bob. Nobody ever needs to be scraped off the rocks below launch because he was relying on a technology that failed him. The only reason that happens is 'cause nobody ever makes the slightest effort to teach or adhere to THIS:
With each flight, demonstrates a method of establishing that the pilot is hooked in just prior to launch.
requirement. Everybody's just way too busy coming up with reasons why it shouldn't be a requirement and "just prior to launch" can mean five or ten minutes and thinking up miraculous electronic gizmos that never seem to get beyond the thought stage.
