[8] In early 1941 Fasson was posted to HMS Nile, the naval headquarters in Alexandria, Egypt, finally returning to sea duty in March 1942 as first lieutenant of the destroyer Petard.
[9] Fasson and Able Seaman Colin Grazier, along with NAAFI canteen assistant Tommy Brown, jumped from the Petard[10] to the deck of the U-559 and entered the sinking submarine, which had water pouring in through seacocks left open by the Germans.
Working in complete darkness, fully aware that the submarine could sink without warning at any time, Fasson and Grazier located documents, which Brown carried up to men in a whaler.
[11] The codebooks that Fasson, Grazier, and Brown retrieved were immensely valuable to the code-breakers at Bletchley Park, who had been unable to read U-boat Enigma for ten months.
[12] Fasson is commemorated with plaques at Bedrule Kirk and the Jedburgh British Legion Club, while his George Cross is held by the Scottish National War Museum at Edinburgh Castle.