The German U-boat U-107, a Type IXB submarine of the Kriegsmarine, achieved significant success during World War II. Kapitänleutnant Günter Hessler commissioned the submarine on October 8, 1940, and led it through its early, highly successful missions. U-107 completed 13 patrols between January 1941 and August 1944, sinking 39 Allied ships and damaging four others. During its second patrol, from March 29 to July 2, 1941, the U-boat operated near the Canary Islands and Freetown, sinking 14 ships totaling 86,699 tons, making it one of the war’s most successful patrols. On August 18, 1944, British aircraft attacked and sank U-107 in the Bay of Biscay, killing all 58 crew members.