"Bras d'Or" was the third vessel to bear that name (see below + B-119 ex PT-3 during World War II under lend-lease) and was built at Marine Industries Limited (MIL) in Sorel, Quebec, the primary contractor being de Havilland Canada, an aircraft company. The Principal Naval Overseer was Commander Donald Clark, CD, RCN, who initiated the project on completion and launch of in 1964. The hull was built upside down out of aluminum and rotated on 22 January 1966 when it was complete. The foil system was constructed from maraging steel.