Re: rusty tanks (was: Trojan)

[shawl@torchlake.com (Jonathan Shawl)]

Hi Vance and all,
I like a guy with a sense of humor!
How I surface from the great depth of 40' (in my 5/16" thick propane tank sub), is
to just blow the trim tank and wait till I get to the surface then blow the MBT.
Nothing gets out of control and I don't waste any air. I did have some fun doing a
fast surface with a fast full blow from 40 or so feet. The sub was moving up so
fast it started making a buzzing sound.
It took a while to figure out what it was. It was the 3/4 " dia by 3' long
magnesium anode rods that are located about a 1/4" from the bumpers. When the
water flows down past them they start to vibrate till they hit the bumper. It's
like a built in alarm for over speed surfacing. Only made it into low orbit for
about a 1/4 second, then splashdown right into the same hole in the water it came
out of. Weeeeee...   Didn't have to call NASA. :-)
Jon Shawl


VBra676539@aol.com wrote:

>       Ascent rates are usually held at 60 feet per minute or thereabouts
> (easy to do as bubbles handily rise at about that rate and you just follow
> them up) unless you are coming up from pretty deep in which case nearly twice
> that is possible.  Regardless, you will slow down in shallower water because
> things can get out of hand very quickly indeed if you do not. The volume of
> air in your MBTs will double every once in a while enroute.  This gets to be
> a very important thing to remember as you near the surface.  Volume doubles
> at 60 from 120--again at 30 from 60--again at 15 from .... well, you'll be
> skyrocketing and out of control by then and Katie-bar-the-door because you're
> coming through!!!!!  The clever psubber will of course remember that the
> shallower he gets (during ascent) the bigger his MBT bubbles get and the
> faster he goes the faster the bubbles get bigger and the faster the bubbles
> get bigger the faster the sub goes and pretty soon he can't dump enough
> through the vents to slow down and there's nothing left but that cabin
> cruiser between him and a space shuttle rescue as he's likely to be in low
> orbit before the thing slows down.
>         In point of fact, you will be pretty steadily venting squirts of air
> from the tanks as you rise to maintain that 60 feet per and watching upward
> pretty carefully for that cabin cruiser.  Then you can stop at 50 feet or so
> and let the bubbles go past and make a nice surface marker so your support
> crew can see you and make sure the area is clear.  Much better than
> contracting NASA for a rescue.
>