Jay and others,
I'm mainly a lake diver where the first to
respond to me would most likely be a dive rescue team, not the coast guard of
navy. For that reason I haven't ruled out the Schrader type tie stem
valve.
The dive rescue teams here work closely with the
fire and rescue people. Most, if not all, dive rescue teams are actually
connected with fire and rescue. The fire and rescue folks use heavy
pillow type air bags for lifting heavy objects and the dive rescue uses
balloon type lift bags for lifting in water. They both use "tire stem
type" connecters. Our dive rescue divers are all equipped with a
hose for discharging pressurized air to fill these bags. I'll ask around
to determine in how wide of an area this is standard. I'm guessing it's
VERY standard since that type of TIRE stem connection is the same
world wide. Maybe there will need to be more then one standard,
depending on the waters your diving in.
When I go out with my sub, I always have a tool
box that stays with the surface guys. That's where I keep
adapters, instructions and things for emergencies. In most cases,
it's your own surface support that will be getting the help for you and they
should have anything that's needed.
For a sub stuck on the bottom, bleeding down
built up pressure in a hull is far harder then injecting in air. To
avoid over pressure on the way up, the hatch could be unlatched and let the
pressure burp out when the sub rises enough, but as Jay points out, it would
have to be a controlled assent. If lift bags were used, the assent could
be controlled by the length of the rope that attaches the bags. For
my sub, my surface support knows that my hatch viewport can be loosened to
vent or unbolted to gain access.
What it comes down to is, most of how a rescue
would go will be determines by how well the rescuers know your sub and how
well they do what is needed. For lake divers like myself, the best
protection is the information and things you have in your topside tool
kit. Most fresh water dive rescue people have never seen a
Psub and don't know first thing about one. Unfortunately, the
best qualified rescue person for any particular sub, is most likely
the person trapped inside.
Jay, I'll get back with you in a few days
about what I find as standards here in fresh water. I'll contact the
rescue teams in the areas I dive.
Dan H.