On Thu, 30 Oct 2003 07:49:51 -0800, Eric Greenwell
wrote:

In article ,
says...
I still fail to understand why any winch or cabel failure should lead
to an accident. With or without radio. With or without wind. With or
without water ballast.
Be prepared.

I seem to recall some launches where the cable became tangled in the
main wheel, when the winch jerked the glider forward, then paused very
briefly. This is caused the glider to pitch up too fast at the start,
and the pilot was unable to release, leading to a crash. Perhaps this
is not what you mean by a winch failure?

That should be a recoverable situation provided that the signalling
channel between launch point and winch can convey three messages:

- take up slack
- all out
- STOP

If, as it appears to be the case at Torrey Pines, the headlamp signals
can't be used to signal STOP then you have an accident waiting to
happen. The launch marshal must ALWAYS be able to signal STOP and be
obeyed without question. Doesn't matter whether the channel is radio,
telephone, coded light flashes or signalling bat provided that it can
transmit those three commands unambiguously.

On the sites where I've winch launched an immediate STOP is signalled
if the glider overruns the cable for any reason. The reason we use the
three phrases listed above (repeated continuously) is that they have
three, two and one syllable and so can be distinguished despite noise
in the winch cab and/or wind noise in the launch marshall's
microphone.

--
martin@ : Martin Gregorie
gregorie : Harlow, UK
demon :
co : Zappa fan & glider pilot
uk :