[PSUBS-MAILIST] a 1atm dry sub or a potential coffin?

[maxxx1@comcast.net]

Hello All,
In my opinion,designing and building wet subs or ambient dry subs from the seat 
of the pants could be a very rewarding accomplishment.However,building a 1atm 
dry sub is another matter,especially one which decends in excess of 150 feet.Now 
your dealing with life support in your self contained environment even if its 
just a bounce dive.Are the O2 and CO2 levels monitered correctly?
Do you have and use a Dragger tube periodically to confirm the gas meters are 
working correctly?.If only one person is in the sub and he blacks out because of 
incorrect gas ratios,then what? Should we carry enough O2 and Soda Zorb to allow 
for a possible rescue from above in case we are hung up on something protruding 
from the wreck we are observing and we can't release ourself, mabee if we could 
see what we were caught on we know what direction or angle to move the sub to 
release ourselves.Could the rope on the wreck be wound around our propeller,no 
way, because we remembered to totally encase the prop and shaft in a wire 
housing.Do we have enough reserve buoyancy to lift the object we are caught on? 
Can we evacuate the sub after equalizing the pressure from 150 feet? 300 
feet?,600 feet? Do we need 2 pony bottles to take with us during out ascent to 
the surface,one air,one a tri-mix with a lable DEEP? What is the record depth 
anyone ever sucessfully evacuated from a sub?
If you go really deep say for example over 600 feet,you may as well be on the 
moon, will you have enough life support for a rescue allowing time for a 
submersible to be flown in,mabee they can spot our bouy which floated to the 
surface and is attached to the sub because we decided to build one on our sub.
Did we decide to spend the $600+ for the underwater phone so we can keep in 
contact with someone on shore.Did we remember to dress with static resistant 
clothing in a potentially O2 enriched environment,and are the lead acid battery 
gasses kept out of the potentially O2 enriched environment cabin? Did we try  to 
eliminate all gear outside the sub which can snag things and hang us up.How many 
volts is that switch we are touching while our knees are immersed in water?.
Did we remember to build an emergency drop weight because we didn't take enough 
scuba air with us to make up for the extra 70lbs we brought aboard,will the drop 
weight work when it is burried in mud? over one cubic foot at say 1000 feet 
depth is how much at  sea level? Did we incorporate any trim weights rather than 
soft ballast tanks? What will happen when the acrylic window hits a submerged 
log while we are decending?
In other words did we remember everything?Do we have prelaunch checklists?
I hope nobody out there is performing manned test dives,in anything but very 
shallow water.Do we have a system for sending the sub down unmanned in excess of 
our maximum dive depth for our test dives? I know we can't think of every 
eventuality, but lets do our homework and find out whats what before we put a 
man inside his potential coffin ie: a 1atm dry sub.
Take Great Care All! 
Robert Rogala
maxxx1@comcast.net