nraoaoc@nmt.edu (Daniel Briggs) (05/30/91)
I'm just musing on the _Student Workshop_ column in the May Parachutist. In particular, I am thinking about the advice on what to do if you have to ride in two tangled canopies. Kevin Gibson writes, "The worst case is being below 1,500 feet, under two hopelessly entangled canopies. The only option is to open one or both reserves without cutting away and get as much useful drag over your heads as possible." Hmmm. Seems like it might be good advice, but I haven't run into it before, and that bothers me. Poynter (_Skydiver's Handbook_) doesn't mention this situation. Parsons (_Canopy Relative Work_) talks about wraps in some detail, but doesn't mention this technique. In fact, he even explicitly talks about landing two people under a single canopy, and makes no mention of reserves at all. At my local DZ, we even had an example of this a few months ago. Two jumpers wrapped, and landed under a single main. While the post incident gossip (20-20 hindsight) was that they were high enough that one of them should have chopped, no one in my earshot said anything like "gee, xxx should have fired his reserve". (BTW, both were badly bruised, but nothing was broken and they were both back jumping within a few weeks. To make matters even worse, they did a down wind landing in light wind. I gather it's rather hard to steer a mess like that.) So I guess what I'm asking is, "If this bit of folk wisdom is a good idea, why isn't it more widely known?" Under what circumstances does the danger of tangling the main and reserve outweigh the benefits of the added canopy area? How about a single controllable main vs. an uncontrollable main + reserve + reserve + mess combination? It seems to me that if both canopies are tangled together and not providing enough lift, (and you're too low to chop), then firing both reserves is the thing to do. In the situation where A's main is tangled in B's lines and is useless but B's main is flying normally, should A fire his reserve? Should B? I'd say yes and no, respectively, but I'm not yet completely decided. The geometry of the wrap is another consideration, too. A might not be *able* to fire his reserve, even if he so desired. What does everyone else think? -- This is a shared guest account, please send replies to dbriggs@nrao.edu (Internet) (505) 835-2974 Dan Briggs / NRAO / P.O. Box O / Socorro, NM / 87801 (U.S. Snail)