Ian,

The type XXI as built did not have wire-guided torpedos but they did have aucoustic homing torpedoes,the T5 'Falke'. After the war the allies examined the T5 and concluded that it was a very 'mearginal' weapon and that it would have been a very poor weapon. This is seen when you look at the overall performance of the Grerman homimg torpedoes during the war. Once the allies decame aware that the germans were using aucoustic homimg torpedoeas they at once introduced countermeasures which largely nulified the threat. The U-Boats had a very low sucess rate with their aucoustic torpedoes against allied ships.

But the germans were planning to overcome some of the issues which they had with their homing torpedoes by fitting wire-gurdance.2 wire-guided torpedoes were under development at the end of the war the 'Lerche' and the 'Grier'. These torpedoes would have been 'steered' to their targets by operators on the U-Boat listening through the hydrophones on the torpedoes nose and guiding the torp onto its target.


As to getting your hands on and old diesel-electric boat your best bet would probably be the former soviet union and one of the big Foxtrot class boats. They were kept in front line service up to the end of the cold war and there should be one knocking around in reasonable condition. My advice is to try the Ukranian navy as i remember seeing a recent photo of several Foxtrots tied up to a peir in Sevastapol. Now wheather or not they would be willing to sell a sub on to a private individual or company is a different matter alltogether.

'Zero-bubble' refers to 'zero-Bubble on the boat'. In the control room of US WWII subs there is a device similar to a sprit level mounted between the hydroplane controls. This sprit level showed if the sub was pointing up or down...and you wanted to keep the sub on an even keel when you were diving and surfacing. Modern subs are not as confined in maneurving...the hull shape and the large flat decks of WWII subs made tham unstable at high speed underwater and unweildly in turns.

Rgrds

Sniper.