The Germans developed this boat by end of the war. One prototype was tested on the East Sea (Ostsee) but blown up when the Russians arrived. The idea was to use existing designs like the V1 engine and the swimmers from the Junker Ju 52. The crew were two, one from the Kriegsmarine to drive, and the second man was from the Luftwaffe to take care for the engine as the Kriegsmarine had no trained staff.
painting: no picture exists, so whatever you like.
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