Re: Minesweeper hulls and speep

[MerlinSub@t-online.de (Carsten Standfuß)]

Carsten from Germany

No ! On surface you have hull resistance and wave resistance.

On diving station you have no wave resistance. Subs with long hull
length on the waterline and big sails / guns /supersctructures 
have normaly higher speed on the surface (German WWII VIIC boats for
example). Boats with short lengths (teardrop) on the construction
waterline like the minesweeper hull or USS Albacore are much faster on
diving station than on the surface. Normaly this kind of hull submerge
by their on bow wave at higher speed on the surface or get out of trimm.
A mixture between both typs are for example USS Nautilus or german WWII
XXI class with is fast on surface and dived. 

I have driven during my study as finally diplom master work a model of a
12 m long autonomus offshore submarine in a test tank of the universiy.
The bow waves runs over the superstructe about a speed of 7 kn and than
the resistance gets very high because of the positive bouancy of the
sub. Means its needs a lot of power to put the wave over the boat. 

If you wants to increasse the surface-speed of the Minesweeper hull
you have to add a superstructure which gives the hull a longer
waterline.

( VII C = U 995, USS Nautilus, USS Albacore, XXI = Wilhelm Bauer
submarines are on display see : WWW.webtagon.com/submarine/ ) 

greetings, Carsten

D. Blake schrieb:
> 
> Surface should be faster than submerged, yes?
> -----Original Message-----
> From: Carsten Standfuß <MerlinSub@t-online.de>
> To: personal_submersibles@psubs.org <personal_submersibles@psubs.org>
> Date: Saturday, August 21, 1999 2:28 PM
> Subject: Minesweeper hulls and speep