From: wrolf@csfb1.uucp (Wrolf Courtney)
Subject: Re: Pony bottles
Organization: First Boston Corporation
Date: Fri, 22 Jan 1993 20:50:18 GMT

In article <9301201437.AA15055@lanmail.NCSC.NAVY.MIL> Mahan_Stephen@LANMAIL.NCSC.NAVY.MIL writes:
>>> (remarks about navy buddy teams, and discipline..)
>
>We use dual ALU 80's, gauged before each dive (common manifold, no
>isolation possible).  1800 psi minimum to enter the water.  Divers use
>US Divers Conshelf XIV regs, no octopus except for the standby diver.
>The left cylinder has a reserve valve which is left closed during the
>dive.  There is NO redundancy for air supply failures except for the
>resources of your buddy (buddy breathing and ascend).  BTW, we NEVER
>plan to do a decompression dive on SCUBA.  When your bottom time is
>about up, the recall device is sounded.  If there's no response, there
>will be an M-80 (explosive) on the way down to attract your attention.
>(It does :-).
>
As I understand it, the Navy does plenty of decompression diving, but only
on surface supplied air.  Is this correct in your experience?

Surface supply is not an option for most wreck divers.  Deco diving is therefore
done on SCUBA, but only with full redundancy.  In wreck infested waters, e.g.
New York/New Jersey, or the British Isles, a lot of the good wrecks are in the
100' to 150' range.  Less than 100' and they get knocked around a lot in the
winter storms, less than 60' and the Coastguard wire drags them as a menace
to shipping.  In this depth range, air diving with decompression stops is the
most practical way to go.  A lot of the deep stuff is done with nitrox or
pure oxygen on the shallow stops, typically only as a safety measure, since
most of these divers are using commercial computers, which can currently
only handle air.

>
>The regs are overhauled every 6 months.  Pressure and depth gauges are
>checked for accuracy/calibrated every 6 months.  Regulators are
>checked before each water entry (air on, free breathing, no free
>flow, tank pressure adequate).  The dive supervisor PERSONALLY inspects
>each diver and fills out a checksheet before each water entry.

Your equipment maintenance and inspection level is probably beyond that of
even the most safety conscious wreck diver (NOT AN OXYMORON).
An especially interesting question for me how often you have fall back to 
plan B (buddy breathing and ascend.)

>
>We are planning to go to octopus rigs for each diver when we are able
>to purchase the additional second stages.
>
How would you feel about the wreck diver standard isolation manifold.
This will mean that you have to move from yoke to DIN, and buy first
stages as well as second stages, but you get complete redundancy, and the
use of all your air for air sharing.
>
>>Safe Diving
>
>We try.  It's been about 16 years at this command since anyone required
>a chamber ride/had an injury requiring time off dive status.  There are
>dives 3-4 times a week.  Please note (for the nitpickers) that this
>does not include NEDU (Naval Experimental Diving Unit) or NDSTC (Naval
>Dive and Salvage Training Center).  Both of these organizations are
>located here but are separate commands.
>
Excellent record!

>
>>Wrolf Courtney
>
>steve


Wrolf Courtney               First Boston Corporation    My opinions are not
(212) 322-7017               Park Avenue Plaza           my employer's.
uunet!csfb1!wrolf            New York, NY 10055
-- 
Wrolf Courtney               First Boston Corporation    My opinions are not
(212) 322-7017               Park Avenue Plaza           my employer's.
uunet!csfb1!wrolf            New York, NY 10055
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