Re: Use of concrete.

[VBra676539@aol.com]

E.M.  & Joe,
	In one of Busby's first books is a little blurb and a couple of 
pictures of concrete pressure vessels being tested out in the deep blue.  
They worked pretty well but were, as you might expect, pretty heavy.  The 
Navy was pursuing several options at the time for all the cold war, 
super-secret stuff and ended up with an aluminum/ceramic material that cost 
the earth but worked very well.    (SOSUS and the like----read Blind Man's 
Bluff about some of that).   Concrete was too homely, I think.  If it wasn't 
new tech and really, really expensive, then the cowboys in blue weren't 
interested.  I'll bet there is a report about it somewhere in the archives. 
though.
	Jim Helle built a plywood and fiberglas sub called Submanaut back in 
the 60s:  Marine ply donuts with glas over the top.  rated to 1000 feet 
(don't know if it actually ever dove that deep).  Now Graham Hawkes is 
building fiberglas subs again, and Phil Nuytton's exo is some kind of 
composite, so I guess nothing is new under the sun except for the details.
Regards,
Vance