The problem with airing them out is one of geometry. Assume that one of the annular hatch o-rings was leaking (which was case in both incidents of my experience). Where is it leaking? Top, sides, bottom? If you pressurize the pod, the risk will be of lifting the hatch off its seat, or dislodging it entirely. That would fall under the heading of bad ju-ju, especially if said pod was only partly flooded when you started. The issue is that you are not venting or blowing something with a top and bottom seal, but rather end cap seals on a horizontal fixture. It won't work and might worsen the problem dramatically. In fact, we could almost certainly categorize it in advance as an 'oh, shit' moment.
That said, I am describing a standard (to my way of thinking) battery pod; ie, Perry, Aquarius, Deepworker style. Some other unit might differ.
One that has interested me for a long time is a very simple 1000' design that George K and I collaborated loosely on--a 5' spherical pressure hull with a single vertical pod mounted to the hull aft (20"X60"). In that instance, if the hatch were secure enough, then you could have a bottom vent and pressurize it from INSIDE the sub to slow the leak. George of course thought that whole thing was stupid and dismissed it out of hand. The blueprint I have of the final(ish) design, which was never built, had a single pod welded into the pressure hull on the centerline with some floatation to hold it up and the thrusters mounted on the aft end.
Vance
-----Original Message-----
From: ShellyDalg@aol.com
To: personal_submersibles@psubs.org
Sent: Wed, Mar 24, 2010 6:08 pm
Subject: Re: [PSUBS-MAILIST] diesel electric propulsion module
In a message dated 3/24/2010 12:35:59 P.M. Pacific Daylight Time,
vbra676539@aol.com writes:
All part of the service, Frank.
Hi Vance. Although some of us newbies like to dream, your perspectives and experience are invaluable. Your advice is always listened to very closely. Thanks. Frank D.
On Hugh's question of a flooded compartment.....Would it be possible or desirable to have an exterior air line connection for battery pods so if one got flooded and the sub came up crooked, the surface crew could blow the flooded pod dry and stabilize the sub long enough to get the people out. It wouldn't take very high pressure at or near the surface. Maybe just a compressor hose from the surface boat at 40 psi.
Frank D.