Battle-class trawler

Battle-class trawlers were naval trawlers built for and used by the Royal Canadian Navy (RCN) during the First World War. Between the wars, some remained in RCN service, but most were transferred to the Department of Marine and Fisheries, where they performed a number of functions, including working as lightships and fisheries patrol vessels. During the Second World War, a number of these trawlers were re-acquired by the RCN, but all the navy's Battle class trawlers were decommissioned soon after the war. A number of the class remained in civilian government and commercial service for years after the war, although most had been disposed of by the early 1960s.

Origins and Military Service
The RCN's Battle class trawlers formed part of the Canadian naval response to Admiralty warnings to Canada about the growing German U-boat threat to merchant shipping in the western Atlantic. Intended to augment anti-submarine patrols off Canada's east coast, these ships were modelled on contemporary British North Sea trawlers, since the standard types of Canadian fishing vessels were considered unsuitable for patrol work. The resulting design was a 130 ft-long vessel with a beam of about 25 ft, a draft of around 13 ft, and a top speed of 10 kn, which made it roughly comparable to the Royal Navy's Castle class trawlers. The 12-pounder gun that was the Battle class trawlers' main armament was considered to be the smallest gun that stood a chance of putting a surfaced U-boat out of action, and they also carried a small number of depth charges. Named after battles of the Western Front during the First World War, they were built by shipyards on the Great Lakes and St. Lawrence River at a cost of some $191,000 each, and entered service relatively late in the war.

Between the Wars
The twelve trawlers remained in commission with the RCN until 1920, and in early 1919, three of them (HMCS Armentières, HMCS Givenchy, and HMCS Thiepval) accompanied HMCS Stadacona on a trip to the west coast via the Panama Canal. In 1920, nine of the class were transferred to the Department of Marine and Fisheries, where they served as buoy tenders, fisheries patrol vessels, and lightships, although one of the ships (Armentières) was soon returned to the RCN. HMCS Loos became a buoy tender, while HMCS Arleux, HMCS Arras, and Givenchy became fisheries patrol vessels. HMCS Messines, HMCS St. Eloi, HMCS St. Julien, and HMCS Vimy were converted to lightships. They remained in service with the Department of Marine and Fisheries throughout the interwar period, but a number were re-acquired by the RCN on the eve of the Second World War and returned to naval service.

Three of the class (HMCS Festubert, Thiepval, and HMCS Ypres) were not transferred to civilian government service, and were rejoined by Armentières in 1923. Remaining with the RCN throughout this time, they served as patrol and training vessels, and some were placed in reserve at various points. In 1924, Thiepval undertook a lengthy trip across the North Pacific to the Soviet Union and Japan to support an ultimately unsuccessful British round-the-world flight attempt. Some six years later, Thiepval struck an uncharted rock in the Broken Islands of Barkley Sound on British Columbia's west coast, and sank. Thiepval was the first of the class to be lost, although Armentières had sunk and been salvaged in 1925.

Second World War
By 1939, only one Battle class trawler, Armentières, remained in active naval service, although Festubert was in reserve and Ypres had just emerged from a refit to become a gate vessel for Halifax's anti-submarine defences. During 1939, the RCN re-acquired five other members of the class: Arleux, Arras, Loos, and St. Eloi on the east coast, and Givenchy on the west coast. The east coast trawlers served primarily as gate vessels at Nova Scotia ports including Halifax and Sydney. In 1940, the British battleship HMS Revenge (06) accidentally rammed and sank Ypres, but without loss of life. On the west coast, Armentières served as an examination vessel, while Givenchy served primarily as an accommodation ship.

Post-War Fates
Following the Second World War, the trawlers that had served with the RCN were soon decommissioned and either sold or returned to civilian government service. Many were broken up in the 1950s or otherwise disposed of in the early 1960s, although two (Armentières and St. Julien) were still in existence in the 1970s, and their final fates remain unclear.

Ships

 * HMCS Arleux
 * HMCS Armentières
 * HMCS Arras
 * HMCS Festubert
 * HMCS Givenchy
 * HMCS Loos
 * HMCS Messines
 * HMCS St. Eloi
 * HMCS St. Julien
 * HMCS Thiepval
 * HMCS Vimy
 * HMCS Ypres