A WW I motor launch - ML 59
Class overview
BuildersElco
Operators Royal Navy
Built1915–1918
In commission1915–1920s
Completed580
General characteristics ML.1–50 series
TypeMotor launch
Displacement34 t
Length75ft
PropulsionPetrol engine
Speed19 kn (35 km/h)
Complement8
Armament
General characteristics ML.51–550 series
TypeMotor launch
Displacement37 t
Length86ft
PropulsionPetrol engine
Speed19 kn (35 km/h)
Complement6
Armament
General characteristics ML.551–580
TypeMotor launch
Displacement37 t
Length80ft
Speed19 kn (35 km/h)
Complement8
Armament
  • 1 × 13-pdr
  • later replaced with 1 × 3-pdr

A Motor Launch (ML) is a small military vessel in Royal Navy service. It was designed for harbour defence and submarine chasing or for armed high-speed air-sea rescue. Some vessels for water police service are also known as motor launches.

World War I service

Although small by naval standards, it was larger than the preceding steam or diesel-engined harbour launches of 56ft 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 80-foot-long (24 m) 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.[1] 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.[2] 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

Royal Norwegian Navy motor launches off Dover during the Second World War.
Royal Norwegian Navy motor launches off Dover during the Second World War.
Examples
Type Length Weight Speed Built Total Lost Designed for
Fairmile A motor launch 110 ft 57 tons 25 knots (46 km/h) 1939 12 Submarine chasing, later minelaying
Fairmile B motor launch 112 ft (34 m) 85 tons 20 knots (37 km/h) 1940-45 1,284 Submarine chasing, many later roles including air-sea rescue
Harbour Defence Motor Launch 72 ft (22 m) 54 tons 12 knots (22 km/h) 1940-45 486 47 Defending harbours; anti-submarine
BPBC Type Two 63 ft High Speed Launch " Whaleback" 63 ft (19 m) 21.5 tons 36 knots (67 km/h) 1940-42 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.[3]

See also

References

  1. ^ Gardiner, p. 101
  2. ^ Jeffrey Charles. "The Rhine Patrol Flotilla Part I: Establishment of the Flotilla".
  3. ^ Gardiner and Chesneau, p. 71