RE: [PSUBS-MAILIST] Self introduction

["Walter starck" <wstarck@ozemail.com.au>]

On Sun, 07 Mar 2004 07:23:23 +1030 "Alexander Foreman"
alexforeman@mailworks.org> wrote:

"I would like to construct a one person dry ambient sub....

Sub requirements:
1. Trailer transportable
2. Light as possible (hopefully below 300kg)
3. Low cost ($2,000 - $10,000)"

A dry ambient sub requires a large enough compressed air supply to
maintain air pressure at the ambient pressure and to replace any air
lost through any variations in depth while submerged.  This means a
large air supply and enough submerged weight to equal the total water
mass displaced.  Achieving all this in a total weight of less than 300
Kg would be impossible.  It could be done in a wet sub but not a dry
one.  

Perhaps there is some confusion here over the term "ambient".  To me it
means an inside air pressure equal to the surrounding (i.e. "ambient')
pressure at any given depth.  An ambient dry sub offers a lot of
disadvantages and no advantages.  It is better to simply put the weight
required to sink the thing into a pressure resistant steel hull and
operate it at an unchanging one atmosphere absolute pressure inside.

Walter Starck
Editor/Publisher
Golden Dolphin Video CD Magazine
www.goldendolphin.com