Rdxfbgrtj

HMS Oribi in 1946
Class overview
Name:	O and P class
Operators:	Royal Navy  Pakistan Navy  Turkish Naval Forces
Preceded by:	L and M class
Succeeded by:	Q and R class
Subclasses:	4 inch O, 4.7 inch O, P
Completed:	16
Lost:	4
Retired:	12
General characteristics P class[1]
Type:	Destroyer
Displacement:	1,690 tons (1,717 tonnes) standard 1,640 tons (1,666 tonnes) 2,250 tons (2,286 tonnes) full load
Length:	345 ft (105 m) o/a
Beam:	35 ft (10.7 m)
Draught:	9 ft (2.7 m)
Propulsion:	2 x Admiralty 3-drum water-tube boilers, Parsons geared steam turbines, 40,000 shp on 2 shafts
Speed:	36.75 kt
Range:	3,850 nmi at 20 kt
Armament:	5 × QF 4 in Mk.V (102 mm L/45), single mounts HA Mk.III 4 × QF 2 pdr Mk.VIII (40 mm L/39), quad mount Mk.VII Up to 6 x QF 20 mm Oerlikon, single mount P Mk.III 4 (1x4) tubes for 21 inch torpedoes Mk.IX 4 × throwers and 2 x racks for 70 depth charges
General characteristics (4.7 inch O class)
Displacement:	1,610 tons (1,636 tonnes) 2,270 tons (2,306 tonnes) full load
Complement:	176 (217 in leader)
Armament:	4 × QF 4.7-inch (120-mm) Mk IX guns, single mounts CP Mk.XVIII 1 × QF 4 in Mk.V (102 mm L/45), mount HA Mk.III 4 × QF 2 pdr Mk.VIII (40 mm L/39), quad mount Mk.VII Up to 6 x QF 20 mm Oerlikon, single mount P Mk.III 4 (1x4) tubes for 21 in torpedoes Mk.IX
Notes:	Other characteristics as per P class
General characteristics (4 inch O class)
Displacement:	1,540 tons (1,564 tonnes) 2,220 tons (2,255 tonnes) full load
Armament:	4 × QF 4 in Mk.V (102 mm L/45), single mount HA Mk.III 4 × QF 2 pdr Mk.VIII (40 mm L/39), quad mount Mk.VII Up to 6 x QF 20 mm Oerlikon, single mount P Mk.III 8 (2x4) tubes for 21 in torpedoes Mk.IX Up to 60 mines (where fitted-for)
Notes:	Other characteristics as per P class

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 subsequently converted to fast second-rate anti-submarine frigates in the 1950s.

Design

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. These ships used the Fuze Keeping Clock HA Fire Control Computer.^[2]

O class

The O-class ships were built in two groups of four. The first group had 4.7 in guns. They were in low-angle mounts which could elevate to only 40 degrees, and were additionally fitted with a 4 in anti-aircraft gun in place of one set of torpedo tubes. The second group had 4-inch (102 mm) guns in high-angle mounts and were fitted to act as minelayers; they 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 one quadruple QF 2-pounder "pom pom" and a pair of quadruple 0.5-inch Vickers A/A machine guns. The latter proved to be outdated, and were replaced by 20 mm Oerlikon guns as they became available, with a total of six single mounts eventually being carried.

P class

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 which did not require the ships to lose a set of torpedo tubes to take on further AA guns.

Ships

O class

All ships survived the war. Five of them were involved in the Battle of the Barents Sea, Onslow being badly damaged. After the battle, the ships were refitted 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 scrap in 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 scrap in 1964 at J Cashmore's, Newport, Monmouthshire.
  
  
  • 
    Obedient †, built by Denny, sold for scrap - 1964.
  
  
  • 
    Opportune †, built by John I. Thornycroft & Company, Woolston, sold for scrap - 1955.
  
  
  • 
    Orwell †, built by Thornycroft, converted to Type 16 frigate 1952, sold for scrap - 1965.
  
  
  
  

* = flotilla leader

† = fitted for minelaying

P class

They served mainly in the Mediterranean, where four ships were lost.

• 
  Pakenham * (ex-Onslow), built by Hawthorn Leslie & Company, Hebburn, disabled by gunfire from Italian Navy torpedo boats Cassiopea and Cigno off Marsala 1943-04-16, abandoned and scuttled by sister ship HMS Paladin (see Battle of the Cigno Convoy.)


• 
  Paladin, built by John Brown, converted to Type 16 frigate 1954, sold for scrap in 1962.


• 
  Panther, built by Fairfield, bombed and sunk by German Junkers Ju 87 'Stuka' aircraft in Scarpanto Strait on 10 September 1943.


• 
  Partridge, built by Fairfield, torpedoed by German Submarine U-565 off Oran, 18 December 1942.


• 
  Pathfinder (ex-Onslaught), built by Hawthorn Leslie, On 11 February 1945, Pathfinder was hit by a Japanese bomber off Ramree, and was taken out of service. She was used as an aircraft target, sold for scrap in 1948.


• 
  Penn, built by Vickers Armstrongs, Walker, sold for scrap - 1949.


• 
  Petard (ex-Persistent), built by Vickers Armstrongs, converted to Type 16 frigate, sold for scrap 1967.


• 
  Porcupine, built by Vickers Armstrongs, torpedoed by German submarine U-602 in the Mediterranean on 9 December 1942 which broke her in two; she was never repaired, but hulked as Pork and Pine, sold for scrap - 1947.

* = flotilla leader

See also

• 
  Type 16 frigate: postwar conversion of some O and P class vessels into second-rate fast anti-submarine frigates.

Notes

References

• 
  Destroyers of the Royal Navy, 1893-1981, Maurice Cocker, Ian Allan,
  ISBN 0-7110-1075-7
  


• 
  Connell, G. G. (1982). Arctic Destroyers: The 17th Flotilla. London: William Kimber. ISBN 0-7183-0428-4.
  


• 
  English, John (2001). Obdurate to Daring: British Fleet Destroyers 1941–45. Windsor, UK: World Ship Society. ISBN 978-0-9560769-0-8.
  


• 
  Friedman, Norman (2006). British Destroyers & Frigates: The Second World War and After. Annapolis, Maryland: Naval Institute Press. ISBN 1-86176-137-6.
  


• 
  Lenton, H. T. (1998). British & Empire Warships of the Second World War. Annapolis, Maryland: Naval Institute Press. ISBN 1-55750-048-7.
  


• 
  March, Edgar J. (1966). British Destroyers: A History of Development, 1892-1953; Drawn by Admiralty Permission From Official Records & Returns, Ships' Covers & Building Plans. London: Seeley Service. OCLC 164893555.
  


• 
  Raven, Alan; Roberts, John (1978). War Built Destroyers O to Z Classes. London: Bivouac Books. ISBN 0-85680-010-4.
  


• 
  Rohwer, Jürgen (2005). Chronology of the War at Sea 1939-1945: The Naval History of World War Two (Third Revised ed.). Annapolis, Maryland: Naval Institute Press. ISBN 1-59114-119-2.
  


• 
  Whitley, M. J. (1988). Destroyers of World War 2. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-326-1.
  

External links

Wikimedia Commons has media related to O and P class destroyer.