Hi James. First off, there aren't any ''silly'' ideas. But here's a few
thoughts on those ideas. I'm no expert, but just some preliminary
thoughts.
On the escape modes you showed, I can't really see where either one would
be effective.
If escape is what's required, the bottom hatch won't help, because you are
likely on the bottom anyway, having tried to fix whatever it was that got you in
that predicament. On Kraka, I think the bottom hatch is for diver in/out at
shallow depth and not escape. To accomplish that, you have to pressurize the sub
to ambient before you open the hatch so water doesn't rush in. May have some use
if you are above the ocean floor and entangled on something. You could probably
exit the sub, break it free and hope you could get back in before it floated
away, but still, only at shallow depth like 120 feet or less. Seems like a lot
of extra work unless you planned on opening the hatch as a diver in/out
anyway.
About the front dome, Sorry, but I don't think that will work either. Jim
K. has a 39 inch plexi dome for his sub located on the nose, but of course it
won't open. That would require a LOT of work, and still won't work as an
escape method. If you open the front dome or the top hatch, you have to
flood the sub to open anything anyway. It won't open with pressure on the
outside.
As I understand it, to exit the sub, the accepted method is to flood the
sub, and with scuba gear on, climb out and swim up. If there's a compressed air
bubble in the tower, it exits the sub with EXPLOSIVE power so you need to be
some distance away from the hatch when it's locks are released. Be a good idea
to have a dive light on board because it's going to be cold, wet, and pitch
black.
Keeping the hatchway clear of any handles etc. will help with exit. Make
sure the hatch is big enough to exit with a scuba tank on.
My hatch is 20 inch dia. and it's a tight fit, but can be done.
I also have a small hole/valve in the hatch dome to release the high
pressure bubble that will form there. Hopefully no violent exit of air when it's
opened. I would think it's better to spend your time/money on making sure the
sub doesn't break in the first place, and having a well practiced plan for the
unlikely event of having to flood and exit.
Redundant systems, back-ups, and practice will give you a better chance of
getting out of the situation than adding another hole to the sub.
Do you plan on diving alone? Or really deep? might be a good idea to add an
exterior fitting/valve so someone attempting rescue could pump air into the
hull, or maybe a method of connecting a cable to the sub remotely ( like a
grabber arm) so you could be hauled up without flooding.
I think Dean had an idea on how to drop a hook onto a sub by following a
wire down that was released by the pilot. Anybody have any thoughts on how to
grab a sub and pull it up? Frank D.