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Old October 16th 11, 02:16 AM posted to rec.aviation.soaring
Martin Gregorie[_5_]
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Default Cable vs rope pulling glider from field

On Sat, 15 Oct 2011 16:35:08 -0700, Fred Weir wrote:

For what it's worth, energy storage is not necessarily bad due to the
fact such storage results in reduced shock loading. As a practical
example, the yachting community will usually moor/anchor their vessels
with a nylon rode or dock line in order to minimize shock damage due to
wind/wave loading. Larger boats using a chain rode depend on the
catenary and weight of the chain to provide cushioning. Three strand
nylon is inexpensive, abrasion resistant and readily available.
Experienced boat folk will also recommend using smaller rather than
larger line in order to maximize "springiness". Obviously, the chosen
line has to be strong enough to do the job though. I think you'll find
most primary climbing ropes contain a parallel strand nylon core for the
same reason.

Understood, and a good point when you're dealing with that sort of
situation.

I use something very similar to the climbing rope you describe on my tie-
downs: I bought a set of those super-cute Claw tiedowns, which came with
exactly that type of rope. Its nice and soft, so can't damage the gel
coat if its kept clean.

However, for ground handling I'd rather use a non-springy rope:
personally I prefer the glider to not catapult itself forward as the
wheel comes out of a mud hole, something I've experienced when moving
club gliders with a golf buggy and a thin, stretchy bit of rope. Thanks
to that infinitely variable transmission a buggy can put out a surprising
amount of torque in those circumstances, really stretching that rope,
with the result that the glider pops out of the hole much faster than
you'd expect.

YMMV of course!


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