Ban CG hooks on air tow? How many gliders would be immediately
grounded? Six of my seven gliders had a CG hooks (only) and I never
kited. How about better training? And, BTW, shoulder straps, no matter
how loose (or not even worn), will not cause a pilot to slip AFT. The
seat back will prevent that. Of course the seat back could fail, or the
seat BELT could be too loose allowing the pilot to slide under the BELT
and that might cause him to pull back on the stick.

On 4/24/2017 4:06 AM, Peter Whitehead wrote:
A manual release system will never be suitable to stop the rapid pitch up caused in this situation. It happens too fast for a manual (actually a sensory-brain-muscle-manual) system, however good the manual system on the tug.

Glider CofG winch hooks are not really suitable for aero-towing, are they? Some of these gliders can't be controlled in pitch once the kiting starts. I have seen people leave their shoulder starts loose on areotowing, and that means the pilot can slide backwards - with hand held on the stick, so that moves too - on pitch-up. (Always use tight shoulder straps on launching, please).

I have lost two acquaintances, both gliding "greats" in such tug upsets. I would say banning the use of aero-towing using a CofG winch hook would be the safest bet to save lives, until an automatic system is available.I suspect this is something EASA and the FAA would sort very quickly ( the banning bit, not the automatic system). Sensors to measure pitch, rate rate of the tug, and also tug/rope angle and angular rate,suitably processed and actioned automatically could allow immediate release BEFORE the critical situation is reached - if we feel that we must continue to launch by aero-tow using CofG hooks.

A rule of nose hooks or "compromise" hooks only, meanwhile, would probably reduce the risk towards zero.

--
Dan, 5J