HM Coastal Motor Boat 4
1916 coastal torpedo boat
HM Coastal Motor Boat 4 is the torpedo boat used when Lieutenant Augustus Agar earned a Victoria Cross for carrying out a raid on Soviet warships in Kronstadt and sinking the cruiser Oleg.
It was one of a large series of small, fast, shallow draught Coastal Motor Boats used during the First World War. She was designed by John I. Thornycroft & Company of Hampton, England, ordered in January 1916, built by them and delivered that summer.
CMB 4 was 45 feet (14 m) long and 8 ft 6 in (2.59 m) in the beam. She displaced 5 tons drawing 2 ft 9 in (0.84 m) of water. Power was a 275 bhp (205 kW) Thornycroft V-12 petrol engine driving a single propeller and achieved a top speed of 24.8 knots (45.9 km/h). The boat was armed with one 18 inch (450 mm) torpedo and two single .303 in (7.62 mm) Lewis machine guns for the attack on Oleg. It was operated by a crew of three.
In May 1916, Lieutenant W. N. T. Beckett took command of the newly built HM Coastal Motor Boat 4. In December 1916 he proceeded to Dunkirk in charge of the 3rd CMB Division and operated on the Belgian coast.
“HM Coastal Motor Boat 4” enters the record as 1916 coastal torpedo boat. Crown Archives preserves that source wording while asking what Coastal, Motor and Boat can confirm, complicate or overturn.
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