HMCS Bittersweet was a Flower-class corvette that served with the Royal Canadian Navy during the Second World War.

[1][2] The Flower-class corvettes originated from a need that arose in 1938 to expand the Royal Navy following the Munich Crisis.

[4] Based on a traditional whaler-type design, the initial Canadian ships of the Flower class had a standard displacement of 950 long tons (970 t).

[3] The Royal Canadian Navy initially ordered 54 corvettes in 1940 and these were fitted with Mark II Oropesa minesweeping gear used for destroying contact mines.

Corvettes were first fitted with basic SW-1 and SW-2 CQ surface warning radar, notable for their fishbone-like antenna and reputation for failure in poor weather or in the dark.

This allowed for the installation of Oerlikon 20 mm (0.8 in) cannon, replacing the Browning and Vickers machine guns.

[12] At the opening of the Second World War, the Canadian shipbuilding industry was incapable of building large, sophisticated warships.

However, Canada required new large, advanced escort ships for national defence and sought to acquire Tribal-class destroyers for the Royal Canadian Navy.

In a deal with the Royal Navy, Canada would construct ten Flower-class corvettes in exchange for two Tribal-class destroyers.

[14] The vessel was ordered in January 1940[15] under the 1939–40 Flower class programme by the Royal Navy from Marine Industries Ltd. in Sorel, Quebec.

To prevent being icebound by the freeze-up of the St. Lawrence River, the incomplete Bittersweet was towed to Liverpool, Nova Scotia to finish construction.

[16] There were delays in the arrival of essential equipment for the British corvettes in Canada and some of them sailed without their main armament as they departed from Canadian dockyards as soon as they were fit for the Atlantic crossing.

[17] Under this agreement, Bittersweet was commissioned directly into the Royal Canadian Navy on 23 January 1941 at Halifax, Nova Scotia.

EG 22 was escorting convoy HX 148 in September and were forced to make a large detour to avoid the German U-boat wolfpack "Markgraf".

Beginning on 31 December, the corvette underwent its forecastle extension at Charleston, South Carolina, keeping the ship out of service until March 1942.

[23] Bittersweet left the group in October 1943 to undergo another refit, this time at Baltimore, Maryland which lasted until November.