[2] Although unimpressed with the trial results that showed that the Fairmile B was not quite maneuverable at slow speeds required for the ASDIC to work correctly, the need for more anti-submarine vessels was so great that the Naval Staff proceeded with the program.

As such, only thirteen Fairmiles built in the Great Lakes region were delivered in 1941; nine in Halifax, Nova Scotia, and four laid up at Sarnia and Toronto, Ontario, due to winter storms.

Intended for anti-submarine patrols at St. John's, Botwood, and at Red Bay on the Strait of Belle Isle, continuing material shortages delayed the commissioning of these vessels to May and June 1942.

[2] Originally designated and painted up as 'Coastal Motor Launch' (CML) 01–36, the Canadian Fairmile B was built of double mahogany wood with an eight-inch (200 mm) oak keel.

[6] In two days, a Fairmile could have its weapons and equipment reconfigured to serve as an escort, minesweeper, minelayer, navigation leader, coastal raider, patrol boat, ambulance or rescue launch.

[7] Regularly deployed in flotillas of six "The Little Ships" relieved larger escort craft urgently needed elsewhere by carrying out anti-submarine patrols, port defence and rescue duties.