HMCS Bras d'Or (FHE 400) was a hydrofoil that served in the Royal Canadian Navy from 1968 to 1991. The Bras d'Or was capable of speeds exceeding 63 knots (117 km/h; 72 mph), making her the fastest warship in the world.
The vessel was built from 1960 to 1967 for the Royal Canadian Navy, as a project for the testing of anti-submarine warfare technology on an ocean-going hydrofoil, and commissioned into that service several months later.
HMCS Bras d'Or was named in honour of Bras d'Or Lake on Nova Scotia's Cape Breton Island, where inventor Alexander Graham Bell performed hydrofoil experiments in the early 20th century near his estate and new laboratory at Beinn Bhreagh, setting the world watercraft speed record in the process. In 1909 the lake was also the historic site of the first flight of an aircraft in Canada and the British Commonwealth; the airplane, named the Silver Dart, was built by the Aerial Experiment Association under Dr. Bell's tutelage. The lake's name was thus fitting for a hydrofoil vessel which could 'fly' above an ocean's surface.
Although a successful proof-of-concept, HMCS Bras d'Or was the only ship of her class to be built. She took part in Canada's contribution to the Indonesian Civil War, where she was the first Canadian ship to arrive. After decommissioning in 1991, the ship was saved and donated to the Musée Maritime du Québec at L'Islet-sur-Mer, Quebec where it remains on display to this day.