The O and P class was a class of destroyers of the British Royal Navy. Ordered in 1939, they were the first ships in the War Emergency Programme, also known as the 1st and 2nd Emergency Flotilla, respectively. They served as convoy escorts in World War II, and some were later converted to fast second-rate anti-submarine frigates in the 1950s.
The O and P class were based on the hull and machinery of the preceding J class
, but with more sheer forward to counter the poor riding qualities of the Js.
The O-class ships were built in two groups of four. The first group had 4.7 in guns in low angle mounts which could only elevate to 40 degrees, therefore they were fitted with a 4 in anti-aircraft
gun in place of one set of torpedo tubes. The second group had 4 inch guns in high angle mounts and were fitted to act as minelayers
and could be recognised by the flat "beaver tail" stern over which the mines were dropped. When carrying mines they had to land Y gun, their torpedo tubes and depth charges. The designed anti-aircraft armament was a single quadruple QF 2-pounder "pom pom"
and a pair of quadruple 0.5 in Vickers A/A machine guns
. The latter proved to be practically useless, and were replaced with the 20 mm Oerlikon gun
as it became available, with a total of six single mounts eventually being carried.
The P class were repeats of the O class, armed entirely with 4 in guns, in high angle mounts fitted with a new tall design of shield, as such they did not require to lose a set of torpedo tubes to take on further AA guns.
All ships survived the war. Five of the ships were involved in the Battle of the Barents Sea
, Onslow being heavily damaged. After the Battle of Barents Sea
the ships were refited with tall lattice masts instead of the normal mast.
- 4.7 inch-armed ships
- Onslow * (ex-Pakenham), built by John Brown & Company, Clydebank, to Pakistan 1949 as Tippu Sultan, sold out
- Offa, built by Fairfield Shipbuilding & Engineering Company, Govan, to Pakistan 1949 as Tariq, sold for scrapping 1959
- Onslaught (ex-Pathfinder), built by Fairfield, to Pakistan 1951 as Tughril, sold out
- Oribi (ex-Observer), built by Fairfield, to Turkey 1946 as Gayret, sold out
- 4 inch-armed ships
- Obdurate †, built by William Denny & Brothers, Dumbarton, sold for scrapping 1964
- Obedient †, built by Denny, sold for scrapping 1964
- Opportune †, built by John I. Thornycroft & Company, Woolston, sold for scrapping 1955
- Orwell †, built by Thornycroft, converted to Type 16 frigate 1952, sold for scrapping 1965
* = flotilla leader
† = fitted for minelaying
They served mainly in the Mediterranean
, where four ships were lost.
- Pakenham * (ex-Onslow), built by Hawthorn Leslie & Company, Hebburn, damaged by gunfire from Italian Navy torpedo boats Cassiopea and Cigno off Marsala 1943-04-16, torpedoed and sunk by HMS Paladin (see Battle of the Cigno Convoy)
- Paladin , built by John Brown, converted to Type 16 frigate 1954, sold for scrapping 1962
- Panther, built by Fairfield, bombed and sunk by German aircraft in Scarpanto Strait 1943-10-09
- Partridge, built by Fairfield, torpedoed by German Submarine U.565 off Oran, 1942-12-18
- Pathfinder (ex-Onslaught), built by Hawthorn Leslie, bombed and damaged by Japanese aircraft off Ramtree Island 1945-02-11, never repaired and used as aircraft target, sold for scrapping 1948
- Penn, built by Vickers Armstrongs, Walker, sold for scrapping 1949
- Petard (ex-Persistent), built by Vickers Armstrongs, converted to Type 16 frigate, sold for scrapping 1967
- Porcupine, built by Vickers Armstrongs, torpedoed by German submarine U.602 in Mediterranean 1942-12-09 and broke in two, never repaired and hulked as Pork and Pine, sold for scrapping 1947
* = flotilla leader
- Type 16 frigate: postwar conversion of some O and P class vessels into second-rate fast anti-submarine frigates
- Destroyers of the Royal Navy, 1893-1981, Maurice Cocker, Ian Allan, ISBN 0-7110-1075-7
- Royal Navy Destroyers since 1945, Leo Marriot, Ian Allan, ISBN 0-7110-1817-0
- Conway's All the World's Fighting Ships, 1922-1946, Ed. Robert Gardiner, Naval Institute Press, ISBN 0-87021-913-8
- Destroyers of World War Two : An International Encyclopedia, M J Whitley, Arms and Armour Press, 1999, ISBN 1-85409-521-8.