A motor launch (ML) is a small military vessel in Royal Navy service. It was designed for harbour defence and submarine chasing. Similar vessels were used by the Royal Air Force for armed high-speed air-sea rescue. Some vessels for water police service are also known as motor launches. Motor launches were slower than motor torpedo boats and motor gun boats

World War I service

Although small by naval standards, it was larger than the preceding steam or diesel-engined harbour launches of 56 ft and coastal motor boats of 40 and 55 ft length. The first motor launches entered service in the First World War. These were five hundred and eighty vessels built by the US Elco company for the Admiralty, receiving the numbers ML-1 to ML-580. They served with the Royal Navy between 1916 and the end of the war, defending the British coast from German submarines.Gardiner, p. 101 Some of the earliest examples, including ML 1, also served in the Persian Gulf from June 1916. After the Armistice of 11 November 1918 a flotilla of 12 Royal Navy motor launches travelled down the Rhine performing duty as the Rhine Patrol Flotilla. The only known surviving example of a World War I era motor launch is ML-286, which now lies in a poor condition on the banks of the River Thames.

World War II types

+Examples Type Length Weight Speed Built Total Lost Designed forFairmile A motor launch57 tons 193912 Submarine chasing, later minelaying Fairmile B motor launch 85 tons 1940–45 1,284 Submarine chasing, many later roles including air-sea rescue Harbour defence motor launch 54 tons 1940–45 486 47 Defending harbours; anti-submarine BPBC Type Two 63 ft high speed launch "Whaleback" 21.5 tons 1940–1942 70 RAF air-sea rescue downed aircrew, particularly in the English Channel

The BPBC Type Two was succeeded by the Type Three 68 ft "Hants and Dorset".

Post-war, many motor launches were taken on as pleasure boats. A number of them are on the National Register of Historic Vessels.Gardiner and Chesneau, p. 71

See also

Harbour launch High-speed launch Motor gunboat Motor torpedo boat Coastal Forces of the Royal Navy R boat – German World War II equivalent

References

Gardiner, Robert, Conway's All the World's Fighting Ships 1906–1921 Conway Maritime Press, 1985. . Gardiner, Robert and Chesneau, Roger, Conway's All the World's Fighting Ships 1922–1946, Conway Maritime Press, 1980. .

External links UK National Register of Historic Vessels Naval Museum of Manitoba Juno Beach A Short History of HMS St Christopher. Royal Navy Coastal Forces training base, mainly for MLs Stoker Harold Siddall Royal Navy, his service in ML.1030 and capture in Crete 1941 "The Movies" A Motor Launch History