Howard, List.
The thing that disturbs me is that even after several years there are still
tethers that can't handle the stress and snap so cleanly. I'm aware of the
programming Deist does and the results have been impressive in stopping so
many cars so many times, safely. What scares me is the fact that with the
potental of eight or so 'liners capable of 400 mph speeds this next year.
This should bring the probable result of two way record runs again. On the
South end of the course there won't be mud for stopping. We don't need more
"Breedlove stops" in a pond somewhere or someone running into a dike.
As for a kevlar tether, the strength isn't necessarily longitudinal from
what I have been able to read ... the impact resistance is based on a
cushioning effect from the woven layers, of which there are several (and the
friction between them is the shock absorbing quality), and the strength of
the covering surfaces. Ballistic nylon is just that, ballistic, tough
enough to slow the original hit
What is needed is some strapping that will hold up under the shock of the
chute deployment jerk. As an example, Polypropylene rope is stronger in
some ways than nylon for the same number of strands and same thickness of
strands. There must be some composite that could be core-spun or
multi-fiber cording that could be manfactured to handle the load.
Just brainstorming and I'm probably all wet but I'm very concerned about the
potential for a dangerous situation.
Wes
PS ... We once towed a '50 Chev 2 door for thirty five miles on a very
cold winter night using two strands of nylon shroud line from a parachute.
The stuff is great until it gets a solid hit, as long as it can stretch a
bit it's just fine.
W
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