Operation Ruthless

The methods of communicating the choice and starting positions, of Enigma's rotors, the indicator, were much more complex for naval messages.

In 1940 Dilly Knox, the veteran World War I codebreaker, Frank Birch, head of Bletchley Park's German Naval Department, and the two leading codebreakers, Alan Turing and Peter Twinn knew that getting hold of the German Navy Enigma documentation was their best chance of making progress in breaking the code.

Fleming liaised with the naval department at Bletchley Park, visiting about twice a month, and was well aware of this problem.

[2] On 12 September 1940, Fleming wrote a note to Godfrey which read: I suggest we obtain the loot by the following means: 1.

When crossing the middle of the English Channel, it would cut one engine and lose height with smoke pouring from a 'candle' in the tail, send out a SOS distress signal and then ditch in the sea.

On 9 February 1940, it had made a forced landing near North Berwick Law after being damaged by a Spitfire over the Firth of Forth.

[3] That this was a major disappointment to the codebreakers can be judged by what Frank Birch wrote in a letter dated 20 October 1940.

Turing and Twinn came to me like undertakers cheated of a nice corpse two days ago, all in a stew about the cancellation of operation Ruthless.