In the early hours of 12 May 1918, while en route for France with US troops under the command of Captain Bertram Fox Hayes, Olympic sighted a surfaced U-boat 500 m ahead. Her gunners opened fire at once, and she turned to ram the submarine, which immediately crash dived to 30 m and turned to a parallel course. Almost immediately afterwards Olympic struck the submarine just aft of her conning tower and her port propeller sliced through U-103's pressure hull. The crew of U-103 blew her ballast tanks and scuttled and abandoned the submarine. This is the only known incident in World War I in which a merchant vessel sank an enemy warship. Olympic returned to Southampton with at least two hull plates dented and her prow twisted to one side, but not breached.
Olympic did not stop, but continued on to Cherbourg. The USS Davis sighted a distress flare and picked up 31 survivors from U-103. It was discovered that U-103 had been preparing to torpedo the Olympic when she was sighted, but the crew could not flood the two stern torpedo tubes.
During the war, Olympic is reported to have carried up to 201,000 troops and other personnel, burning 347,000 tons of coal and traveling about 184,000 miles. Her impressive World War I service earned her the nickname Old Reliable.
To all those lost that terrible night.
