 The vessel was built by the Casey Boat Building Company Inc., of Fairhaven, Massachusetts, in early 1943, as a Design 235 U.S. Army Air Force crash rescue boat, and designated P-102.As the largest of the crash boats the Design 235-class were equipped with emergency medical facilities which could accommodate up to 23 people, which the crew of 12 were all cross-trained to operate.Under the name USCB "Shearwater", the United States Crash Boat operated from the Naval Air Station Argentia until 10 September 1947, when she was purchased by the Newfoundland Tuberculosis Association for US$5,000 and converted into a floating clinic.