Bungee at Long Myndd

On 3 Aug, 14:30, Peter Higgs wrote:

As for the recent Winch Launching debate, we did find that the woven
Dynema cable used on a SkyLaunch winch did break quite often. * This was
thought to be because it was used in muddy conditions, or on an abrasive
tarmac runway. *It was replaced by some sort of normal 3 strand plastic
rope (8 and 10 mm.) which was easier to splice, and gave better results.
These nylon ropes do stretch a bit first on 'All Out' and can give a
very quick initial acceleration, only limited by the weak link I guess.

I'd be very nervous about using something as stretchy as nylon for
winching. There's a hell of a lot of energy in a stretched rope, and
it all goes kinetic in a break. In fact, I'd go so far as to say that
for safety reasons I wouldn't go anywhere near a nylon winch cable,
and I certainly wouldn't launch on one.

Ian

Too right about the KE in nylon. I've seen what happens when someone
tried to cut a 1" rope under tension - it explodes.





I'd be very nervous about using something as stretchy as nylon for
winching. There's a hell of a lot of energy in a stretched rope, and
it all goes kinetic in a break. In fact, I'd go so far as to say that
for safety reasons I wouldn't go anywhere near a nylon winch cable,
and I certainly wouldn't launch on one.

Ian