RJ Skinner Loss of Ark Royal Commemorative Cover. 5x8 inches HMS Ark Royal (pennant number 91) was an aircraft carrier of the Royal Navy that served during the Second World War. She was torpedoed on 13 November 1941 by the German submarine U-81 and sank the following day: one of her 1,488 crew members was killed. Her sinking was the subject of several inquiries, with investigators keen to know how the carrier was lost, in spite of efforts to save the ship and tow her to the naval base at Gibraltar. They found that several design flaws contributed to the loss, which were rectified in new British carriers.