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From: <john.r.strohm@BI*.co*>
Date: Sun, 18 Jan 1998 23:05:50 -0500 (EST)
Subject: Re: 3 missing in WPB Fl / Divers Supply "coverup"! FROM rec.scuba, s
To: cobber@ci*.co*
Cc: dlv@ga*.ne*, techdiver@aquanaut.com
>What on earth gear configuration could make this guy -60lbs? Why didn't 
>they hook a lift bag to him? Was their END too high for them to function?

Jim, I'm butting in and guessing, because I've been doing some thinking
about this incident myself.

Assuming the guy was diving a decent two-piece (jacket and john) wetsuit
(which he needed for the water temps Dan is reporting), he is going to need
something like 40 lbs of negative buoyancy to get himself and his suit
neutral at the surface.  Some of that will be in his tankage and other
gear, the remainder will be on his weightbelt.  Assuming double 100s, a
steel 72 and an aluminum 80, he's carrying about 28 lbs of gas, which the
wings are lifting at the start of the dive.  At 250 fsw, call it 8.6 ata,
for all practical purposes the suit has gone to zero buoyancy, maybe even
negative, and his wings now have to "take up the slack" and lift that 40
lbs.

We're talking almost 70 lbs of required lift, just to get neutral at the
bottom.

There was a similar death a year or two ago.  The guy was negative on the
bottom, with everything inflated.  It wasn't until he'd been brought up
quite a ways that he became neutral.

Thinking about this has about convinced me to start saving for *my* TLS
350.  I don't need a problem like this, ever.

--John
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