Andrewwhyte 1 #26 October 18, 2005 QuoteQuoteWill this lead to an increase in opening shock deaths? Do you think the difference between this material will be that much more significant than the difference between F111 and ZeroP? I'm not even sure you could say ZP opens harder than F111 or causes more opening shock deaths due to the canopy fabric? Or does it? I don't know, just trying to put it into a perspective. I'm not sure there is a difference in the coefficient of elasticity of F-111 and ZP. As far as I know the problems with opening shock on most modern parachutes verses older ones tend to be thought to be related to the elastic differences between dacron and spectra lines. There are certainly others on these forums more knowledgeable than me on this subject. Quote Share this post Link to post Share on other sites
mjosparky 3 #27 October 18, 2005 QuoteI recall problems encountered with ejection chutes when they started using things like kevlar lines on nylon chutes. The force from the non-stretchable kevlar lines was transmitted to the line attachment points, and new techniques had to be developed to keep the lines from just popping off. It wasn't Kevlar lines. They were using Kevlar for lateral bands and in some cases to reinforce the radial seams. During high speed deployment (ejection seat) the canopy expands like a big balloon initially. When the bands and the seams can’t expand with the rest of the canopy, the rest of the canopy goes away. We did a series of tests on a canopy, ACE, that was designed to replace the GQ-1000 in the F-18 head box. The tests were at 300 KEAS with a load of 300 pounds. The canopy came out of the head box, went BANG, and all that was left was a skeleton consisting of Kevlar. All the nylon was gone. Now if the body of the canopy is made of a zero stretch material the explosive forces of deployment will end up going somewhere. SparkyMy idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
mark 102 #28 October 18, 2005 QuoteTwo things I remember from Dan's presentation at the '05 symposium: It was reinforced with another layer of fabric. The canopy weighed less than the lines. Also, he was jumping regularly. Seemed to work for him. That's three things. The reinforcing was just at the line attachment points. Mark Quote Share this post Link to post Share on other sites
slotperfect 7 #29 October 18, 2005 I emailed the president of Cuben Fiber and asked him to post his input directly to this thread. Cross your fingers!Arrive Safely John Quote Share this post Link to post Share on other sites
MikeForsythe 0 #30 October 19, 2005 But while waiting everyone can start reading HEREand HERE.Time and pressure will always show you who a person really is! Quote Share this post Link to post Share on other sites
