Chad Irby wrote in message m...
In article ,
Alan Minyard wrote:

On Mon, 13 Oct 2003 00:00:35 GMT, Chad Irby wrote:

Note that the German WWII sub coatings *did* work a bit. At least,
until they were exposed to sea water, which deposited a lot of
microscopic material on them which screwed up their stealth properties.
They also didn't "stick" very well.

Well, that sort of supports "completely in-effective" doesn't it :-)

It worked fine. As long as you kept it in pure fresh water...

Chad,

Alberich's problem was not the material itself but the adhesive
applied to the sub to attach the sheets. This problem was fixed by the
time Alberich was applied to the Type XIII Boats in Feb '45.
If you are talking about the stealth schnorkels then that was another
material Tarnmatte...
In addition to Alberich the Type XXI also had a stealth V-belt silent
drive. Using the belt drive the Type XXI could achieve 6 knots
underwater in silence. This was proven when the USN testing U-2513 in
late 1946 could not detect the boat reliably even when it was at a
range of only 220m.
A photo of the V-belt drive can be seen in the book "The Type XXI
U-Boat" by Fritz Kohl & Eberhard Rossler (Naval Institute Press, 1991)
on page 44.

Rob