I read about the 1/2 degree accuracy in the GHG system with the steerable pod in the XXI, in Rosslers excellent book. I didn't know it could be used to guide a torpedo to within 20 meters @ 2km range. Thats astonding!

Can you tell us where you got that info from?


I aggree the whole Walter design effort was some what of a waste, but he pointed the way ahead towards Schnorkel subs and fishboat designs from 1934 on. The rearwards firing slanted torpedos were an interesting idea.Too bad the KM hadn't the sence to adapt his findings.

In Rosslers book it becomes apparent that the bulk of the underwater resistance generated by a Uboat design was in the conning tower. By moving from a "winter Garden" bridge festoon with Flak, to a stream lined Walter bridge, you could 1/2 the Uboats underwater resistance . This in effect doubled the hp of the engine[ ineffect], which inturn should alow an increase in under water speed of 25%. Further late war upgrading of these genetrators allowed over 50% increase in generator power. Combined that could have allowed a 45% increase in underwater speed...maybe from 7.6 knots to 11 knots. Almost the same class as the XXIII.

However the XXIII also had more than double the electrial endurance 175-80nm. To get that increase out of the Type VII design you'd have to reduce the fuel bunkerage by 1/2 and loose all the reserve torpedos. That would turn the boat into a shorter range coastal boat like the XXIII.