Unterseeboot 413

Unterseeboot 413 (U-413) was a Type VIIC submarine of the Kriegsmarine. Her keel was laid down on April 25, 1941 by Danziger Werft[?], of Danzig. She was commissioned June 3, 1942, with Oberleutnant zur See Gustav Poel in command. Poel commanded her (receiving a promotion to Kapitänleutnant) until April 19, 1944, when he was relieved by Oblt. Dietrich Sachse who commanded her until her loss.

U-413 conducted eight patrols, sinking six ships totaling of 37,985 tons.

On November 19, 1942, U-413 was attacked by a British Lockheed Hudson[?] aircraft with five bombs and was damaged so severely that she had to return to base.

U-413 did not suffer any casualties until August 20, 1944, when she was sunk in the English Channel by depth charges from the British escort destroyer HMS Wensleydale[?] and the destroyers HMS Forester[?] and Vidette[?]. 45 of her crew were killed; there was one survivor.

Neal Stephenson's novel Cryptonomicon features a fictitious U-413, a milchkuh. It is possible that Stephenson picked the number of the boat not for historical accuracy but rather because it is the product of two primes, 7 and 59.