The Algerine-class minesweeper was a large group of minesweepers built for the Royal Navy (RN) and the Royal Canadian Navy (RCN) during the Second World War. 110 ships of the class were launched between 1942 and 1944.
By 1940 the Royal Navy had realized that the Bangor-classminesweepers were too small to handle the equipment needed to handle magnetic mines. A bigger ship was designed, ironically about the same size as the older Halcyon class that the Royal Navy had rejected earlier as too large and expensive for mass production. The size of the new ship made them suitable for use as ocean-going escort ships and many were used in that role to fill a critical shortage of escorts. In fact most of the ships built for the RCN were solely employed as such and were fitted with more dedicated anti-submarine weapons than the RN ships. To maximise production, alternate designs were made to use either steam turbines or reciprocating steam engines.
The turbine-powered ships displaced 850 long tons (860 t) at standard load and 1,125 long tons (1,143 t) at deep load while the reciprocating group displaced 1,010–1,030 long tons (1,030–1,050 t) at standard load and 1,305–1,325 long tons (1,326–1,346 t) at deep load. The hull's dimensions were the same for both groups and the ship measured 225 feet (68.6 m) long overall with a beam of 35 feet 6 inches (10.8 m). The turbine group had a draught of 11 feet (3.4 m) while the reciprocating ships sat 1 foot 3 inches (0.4 m) deeper in the water. The ships' complement consisted of 85 officers and ratings.
The Algerine class was armed with a QF 4 in (102 mm) Mk Vanti-aircraft gun and four twin-gun mounts for Oerlikon 20 mm cannon. The latter guns were in short supply when the first ships were being completed and they often got a proportion of single mounts. By 1944, single-barrel Bofors 40 mm mounts began replacing the twin 20 mm mounts on a one for one basis. All of the ships were fitted for four throwers and two rails for depth charges. Many Canadian ships omitted their sweeping gear in exchange for a 24-barrel Hedgehogspigot mortar and a stowage capacity for 90+ depth charges.
M900 Adrien de Gerlache (ex HMS Liberty, acquired 1949 - stricken 1969)
M901 Georges Lecointe (i) (ex HMS Cadmus, acquired 1950 - stricken 1959)
M901 Georges Lecointe (ii) (ex HMCS Wallaceburg, acquired 1959 - stricken 1969)
M902 Van Haverbeke (i) (ex HMS Ready - acquired 1951 - stricken 1960)
M903 Dufour (i) (ex HMS Fancy - acquired 1951 - stricken 1959)
M903 Dufour (ii) (ex HMCS Winnipeg - acquired 1959 - stricken 1966)
M904 De Brouwer (i) (ex HMS Spanker - acquired 1953 - stricken 1966)
M905 De Moor (ex HMS Rosario - acquired 1953 - stricken 1966)
Happy Return (J466)
After the war, a number continued in service as patrol boats, survey ships, and training ships. Some were sold to other navies or into merchant service. At least one - HMS Pickle (commanded by Lt. Cmdr. Hallifax and, later, Lt. Cmdr, Collins) - was still engaged in minesweeping duties in British waters as late as 1955. At least one Algerine is still in service with the Royal Thai Navy: HTMS Phosampton (ex-HMS Minstrel).