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From: nraoaoc@nmt.edu (Daniel Briggs)
Newsgroups: rec.skydiving
Subject: Open your reserve in a low wrap?
Message-ID: <1991May30.095701.19836@nmt.edu>
Date: 30 May 91 09:57:01 GMT
Reply-To: dbriggs@nrao.edu (Daniel Briggs)
Organization: National Radio Astronomy Observatory, Socorro NM
Lines: 41

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?

-- 
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