No problem. Pressure in the sub is surface or even slightly negative
as O2 is absorbed in the body and CO2 in the scrubbers.

There are a couple of snaps and creaks as the steel sphere compresses.
Quite startling. I think it's about 3/8 inch smaller in diameter on
the bottom than at the surface.

The highest I've been in my 172 is now just about the same as the
lowest I've been in the sub. I'm symmetrical about sea level.

--

Roger Long



" Blueskies" wrote in message
...

Fancy! I suppose you don't just go hop in an airplane and climb to
10,000' after a dive like that. Interesting
technology...