One of the most valuable gifts I got from the Vancouver Psubs
convention is a close-up picture of the main thru hull
/ penetration panel on the Deepworker 2000. Like Alec has promoted
for several years, Phil has clustered 11 hull penetrations into a
single removable SS plate. The central penetration has a Swagelok
3/8 inch, 3-way ball valve installed with the valve stem coming through the
cedntral penetration into the cabin. This valve stem has a modify handle
with a red ball. When the handle is in the horizontal position, all
ports are closed. When the valve handle is moved down, air trapped in
the MBT is released to the water and the boat decends. When the valve
handle is moved up, the valve is ported such that compressed air is forced
into MBT and the boat ascends. While this MBT vent valve option will not
work for all psub applications (valve needs to be located above the highest
point in the MBT), for small boats with a single MBT or a set of
straddle MBTs , this is a very elegant solution. It is easy to
maintain, keeps all the HP air out of the boat, it is very intuitive to use
and minimizes the number of valves and tubing. As it uses
Swagelok fittings, it has bubble tight seals. To my knowledge, the
Deepworker only uses the MBT and not a VBT so that is this an extremely simple
and bullet proof ballast system.
Cliff