SM U-103

SM U-103 was an Imperial German Navy Type U 57 U-boat that was rammed and sunk by HMT Olympic during the First World War. U-103 was built by AG Weser in Bremen, launched on 9 June 1917 and commissioned 15 July 1917. She completed five tours of duty under Kptlt. Claus Rücker and sank eight ships totalling before being lost in the English Channel on 12 May 1918.

Sinking
In the early hours of 12 May 1918, the surfaced U-103 sighted Olympic, the older sister of RMS Titanic, which was carrying US troops to France. The crew prepared to launch torpedoes from her stern torpedo tubes but was unable to flood them in time before the submarine was spotted by Olympic, whose gunners opened fire as the transport ship turned to ram.

SM U-103 started to crash dive to 30 m in an attempt to turn to a parallel course to the liner. But there was not enough time before the port propeller of Olympic sliced through the submarine's pressure hull just aft of its conning tower. The crew of U-103 blew ballast tanks before scuttling their sinking submarine. Nine crewmen lost their lives. Olympic did not stop to pick up the survivors but continued on to Cherbourg. USS Davis (DD-65) later sighted a distress flare and took 35 survivors to Queenstown.

Wreck
The remains of U-103 lie at a depth of 90 m in the English Channel about midway between England and France (49.26667°N, -4.85°W). Its deep location makes it largely inaccessible to divers but the wreck was surveyed and identified by a remotely operated underwater vehicle in 2012.