U-Boat victories and claims

[John Beaman]

Hi Adriano:

Ultra is a fantastic and totally necessary source for evaluating WWII history, but it is not fool-proof. The Kriegsmarine was much more security conscious than the Luftwaffe. Its Enigma machines not only used a 4th wheel early on but they religiously changed rotations and set-up tests. This made it extremely difficult for Bletchley Park to break these codes (Fish, Shark, etc). They did it early, but by late- '41/early '42 there was not much. Not until early 1943 (IRRC) were they "reading" naval transmissions and even then it was not steady or sometimes very fragmentary.

So, Ultra would not likely have confirmed U-Boat sinkings with any regularity. Plus, the only clue that a boat was missing would have been repeated attempts by the HQ to contact the boat.