[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
> Hi,
> 
> Anyone is free to design and operate the way they decide. If they get hurt I 
> hope they remember about personal resposibility instead of the current "I am a 
> victim so I'll sue" mentallitly.
> 
> The tried and true methodologies are safer by the fact they are the ones more 
> widely adopted. Hence they have a proven track recored. I would suggest anyone 
> new to submersibles to build one of the more traditional designs before 
> experimenting. These guys were not operating safely. In the words of Ron 
> Wanttaja:
> 
>     Why we [Ron and Fitz] didn't both get embolisms and 
>     gawd knows what else, I'll never know.
> 
> However lets move on. In light of their experiences and excellant report. What 
> can we learn?
> 
> 1. Shape of ballast tanks can be critical.
> 2. Completely flood and blow soft MBT on the surface.
> 3. Do not rely on MBT, especially soft MBT for trim control. Unless of course 
> that IS your trim control and have designed a way to CONTROL it.
> 4. Do initial manned tests in shallow water. Perhaps as shallow as 10 feet or 
> what ever it takes to get completely under water by a small amount. Perhaps a 
> foot. In subsequent tests move into deeper and deeper water.
> 5. Have a way to bail out if things go awry.
> 6. Try, try again.
> 
> Regards,
> Ray
> 
> DJACKSON99@aol.com wrote:
> > 
> > It bothers me that we would see this as a way "*not*" to build a sub. I think 
> there is a lot to be said for experimentation and courage as a design approach. 
> While it is not an approach for everyone, it has many merits. It assures full 
> ownership for success and failure, maintains the possibility for discovering 
> something new, and it makes the endeavor exciting, adventurous, and fun. I think 
> too many of us are afraid to do something because it's dangerous, or we will 
> likely fail. What inventions and discoveries are we missing because we teach our 
> children to never take a risk? Is there no place in life for danger and 
> adventure? Isn't it possible to lose your life because you are so worried about 
> protecting it?
> > If design by experimentation and courage scares you then fine, go on and copy 
> someone else's work, and make sure your children wear their bike helmets. I am 
> certainly not the brightest person walking around, and may very well end up with 
> a Darwin award, but I will be adventurous, learn, invent, and enjoy my life. And 
> damn the obstacles erected by everyone who lack the balls or imagination to do 
> build something from scratch.
> > 
> > Doug Jackson
> > 
> > In a message dated 12/22/2003 2:34:32 AM Eastern Standard Time, NeophyteSG 
> writes:
> > 
> > > Ran across this example of how *not* to design and build a
> > > 2-person ambient.
> > >
> > > http://home1.gte.net/ikvamar/avlinks/sub.htm
> > >
> > > Warm Regards
> > > Shawn