Sank after a collision in Loch Striven on the morning of 6th March 1945.
XE-11 had been calibrating instruments in Loch Striven. The Submarine was changing depth and was in collision with a Ministry of War Transport Boom Defence Vessel (previously the Fleetwood Steam Trawler Norina which was laying buoys.
When American submarine Swordfish is torpedoed the survivors are picked up by a passing German U-boat but an outbreak of meningitis threatens all aboard.