German submarine U-100 (1940)

German submarine U-100 was a Type VIIB U-boat of the Nazi German Kriegsmarine during World War II. She, given her short-lived existence, was one of the most successful and deadly U-Boats to have served in the conflict.

First patrol
The boat was launched on 10 April 1940, with a crew of 53, under the command of Kapitänleutnant Joachim Schepke. On her first active patrol, U-100 came into contact with two Allied convoys, OA-198 and OA-204. She shadowed both convoys with the following results:


 * 16 August 1940:
 * Sank the British 4,864 ton Empire Merchant, sailing with convoy OA-198
 * 25 August 1940:
 * Sank the British 5,471 ton Jamaica Pioneer
 * 29 August 1940:
 * Sank the Swedish 2,373 ton Alida Gorthon, a member of convoy OA-204
 * Sank the British 2,393 ton Astra II, part of convoy OA-204
 * Sank the British 4,608 ton Dalblair, from convoy OA-204
 * Damaged the British 5,498 ton Hartismere, sailing with convoy OA-204
 * Sank the British 6,103 ton Empire Moose, a member of convoy OA-204

Second patrol
U-100 departed for her second active patrol on 11 September 1940, coming into contact with the Allied convoy HX 72, with the following results:


 * 21 September 1940
 * Sank the British 4,608 ton Dalcairn
 * Sank the British 8,286 ton SS Canonesa
 * Sank the British 10,364 ton Torinia
 * 22 September 1940
 * Sank the British 3,940 ton Scholar
 * Sank the Norwegian 6,031 ton Simla
 * Sank the British 6,586 ton Empire Airman
 * Sank the British 10,525 ton Frederick S Fales

Third patrol
After resupplying, U-100 departed for her third active patrol on 12 October 1940. She came into contact with two Allied convoys, HX-79 and SC-7, with the following results:


 * 18 October 1940:
 * Damaged the Dutch 2,118 ton SS Boekelo, a member of convoy SC-7
 * Damaged the British 5,458 ton SS Shekatika, part of convoy SC-7
 * 19 October 1940:
 * Damaged the British 4,155 ton SS Blairspey, from convoy SC-7
 * 20 October 1940
 * Sank the British 5,452 ton Loch Lomond, sailing with convoy HX-79
 * Sank the British 6,218 ton Sitala, a member of convoy HX-79
 * Sank the British 8,230 ton Caprella, part of convoy HX-79

Fourth patrol
U-100 departed on her fourth patrol on 7 November 1940. On 22 November She came into contact with the Allied convoy SC-11 and began to shadow it with the following results:


 * 23 November 1940
 * Fatally damaged the Norwegian 2,205 ton Bruse
 * Sank the Norwegian 2,694 ton Salonica
 * Sank the British 3,136 ton Leise Mærsk
 * Sank the Dutch 3,628 ton Ootmarsum
 * Sank the Dutch 3,636 ton Bussum
 * Sank the British 4,562 ton Justitia
 * Sank the British 4,740 ton Bradfyne

Fifth patrol
U-100 left for her fifth active patrol on 2 December 1940, sinking two vessels from convoy OB-256, then a third solo vessel. They were:


 * 14 December 1940:
 * Sank the British ship Euphorbia, 3,380 tons, part of convoy OB-256
 * Sank the British ship Kyleglen, 3,670 tons, part of convoy OB-256
 * 18 December 1940:
 * Sank the British ship Napier Star, 10,116 tons

Sixth and final patrol
U-100 departed on her sixth and what would be her final patrol on 9 March 1941. She approached convoy HX 112 from astern in the pre-dawn hours of 17 March, but was detected at a range of 1,000 meters by the Type 286 RADAR aboard HMS Vanoc (H33). U-100 was the first U-boat to be so discovered during World War II; she was rammed and sunk by Vanoc while attempting to submerge. Another destroyer, HMS Walker, was also present. Six of the boat's 53 crew-members survived, spending the remainder of the war as POWs. Schepke was not one of them..