[3] 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.

[1] 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.

From 1947 the vessel sailed to isolated outports on the coast of Newfoundland, screening residents for tuberculosis (TB), which was a leading cause of death on the island.

[5] Under the command of Captain Peter Troake from 1950, the ship was fitted to provide chest X-rays, and also carried out vaccinations for TB and polio, and tested for diabetes.

By 1970, the decline in rates of infection, and the improvements in road access on the island, meant that the services of Christmas Seal were no longer required.