Relentless As Built, December 1942
History
United Kingdom
Name	HMS Relentless
Owner	Royal Navy
Ordered	May 1941
Builder	John Brown & Company, Clydebank, Yard No.590
Laid down	20 June 1941
Launched	15 July 1942
Commissioned	30 November 1942
Out of service	Reserve Fleet - November 1947
Reinstated	1952. Converted to Type 15 frigate
Identification	Pennant number H85
Honours and awards	SABANG 1944
Fate	Scrapped 1971
General characteristics As R-class destroyer
Class and type	R-class destroyer
Displacement	1,705 tons (1,732 tonnes) 2,425 tons (2,464 tonnes) full load
Length	358.25 ft (109.19 m) o/a
Beam	35.75 ft (10.90 m)
Draught	9.5 ft (2.9 m)
Propulsion	2 x Admiralty 3-drum water-tube boilers, Parsons geared steam turbines, 40,000 shp (30,000 kW) on 2 shafts
Speed	36 kn (67 km/h)
Range	4,675 nmi (8,658 km) at 20 knots (37 km/h)
Complement	176
Sensors and processing systems	Radar Type 290 air warning Radar Type 285 ranging & bearing
Armament	4 × QF 4.7-inch (120-mm) Mk.IX guns single mounts CP Mk.XVIII 4 × QF 2 pdr Mk.VIII (40 mm L/39), quad mount Mk.VII 2 × 2, 4 × 1 QF 20 mm Oerlikon, single mount P Mk.III[1] 8 (2x4) tubes for 21-inch (530 mm) torpedoes Mk.IX 4 × throwers & 2 x racks, 70 depth charges
General characteristics As Type 15 frigate
Displacement	2,300 tons (standard) 2,700 tons (full load)
Length	358 ft (109 m) o/a
Beam	37.75 ft (11.51 m)
Draught	14.5 ft (4.4 m)
Propulsion	2 × Admiralty 3-drum boilers, steam turbines on 2 shafts, 40,000 shp
Speed	31 kn (57 km/h) (full load)
Range	4,675 nmi (8,658 km) at 20 knots (37 km/h)
Complement	174
Sensors and processing systems	Radar Type 293Q target indication. Type 277Q surface search Type 974 navigation Type 262 fire control on director CRBF Type 1010 Cossor Mark 10 IFF Sonar: Type 174 search Type 162 target classification Type 170 attack
Armament	1 × twin 4 in gun Mark 19 1 × twin 40mm Bofors Mk.5; 2 × Limbo Mark 10 A/S mortar

HMS Relentless was an R-class destroyer of the Royal Navy that saw service during World War II. She was later converted into a Type 15 fast anti-submarine frigate, with the new pennant number F185.

Commissioned at Greenock on 30 November 1942, Relentless performed anti-submarine escort duties and patrolling activities in the South Atlantic and Indian Ocean for the balance of the war.^[2]

From 1946 until 1949 Relentless was held in reserve at Chatham and then Harwich. From 1949 until 1951 she underwent conversion to a Type 15 Anti-Submarine Frigate.^[3] In 1951–1952 she was the leader of the 3rd Training Squadron.^[4] In 1953 she took part in the Fleet Review to celebrate the Coronation of Queen Elizabeth II.^[5]

In 1954 she was involved in a serious collision with the destroyer Vigilant.^[6] From October 1956 until 1964 she was held in reserve at Gareloch, Chatham and Rosyth.

On 27 June 1964 she was re-commissioned to serve as part of the 29th Escort Squadron, to replace the destroyer Diana.

Relentless was placed on the disposal list in August 1965 and was sold to Thos. W. Ward for scrapping at Inverkeithing in 1971.

The Commanding Officer from 1951 to 1952 was Captain Michael Le Fanu RN.^[7]

• Colledge, J. J.; Warlow, Ben (2006) [1969]. Ships of the Royal Navy: The Complete Record of all Fighting Ships of the Royal Navy (Rev. ed.). London: Chatham Publishing. ISBN 978-1-86176-281-8.
• 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.
• Marriott, Leo, Royal Navy Destroyers Since 1945. Ian Allan, 1989. ISBN 0-7110-1817-0
• Raven, Alan & Roberts, John (1978). War Built Destroyers O to Z Classes. London: Bivouac Books. ISBN 0-85680-010-4.
• Richardson, Ian (August 2021). Osborne, Richard (ed.). "Type 15 Frigates, Part 2: Ship Histories". Warships: Marine News Supplement. 75 (8): 381–391. ISSN 0966-6958.
• 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.

v t e Q- and R-class destroyers
Q class	Royal Navy Quilliam [leader] Quadrant Quail Quality Queenborough Quentin Quiberon Quickmatch  Royal Australian Navy Quadrant Quality Queenborough Quiberon Quickmatch
R class	Royal Navy Rotherham [leader] Racehorse Raider Rapid Redoubt Relentless Rocket Roebuck
Other operators  Indian Navy Rajput (ex-Rotherham) Rana (ex-Raider) Ranjit (ex-Redoubt)  Royal Netherlands Navy Banckert (ex-Quilliam)
Preceded by: P class Followed by: S class
List of destroyers of the Royal Navy List of destroyers of the Royal Australian Navy

v t e Type 15 frigates
Royal Navy	Grenville Rapid Relentless Rocket Roebuck Troubridge Ulster Ulysses Undaunted Undine Urania Urchin Ursa Venus Verulam Vigilant Virago Volage Wakeful Whirlwind Wizard Wrangler Zest
Royal Australian Navy	Quadrant Queenborough Quiberon Quickmatch
Royal Canadian Navy	Algonquin Crescent Crusader
South African Navy	Jan van Riebeeck (ex-Wessex) Simon van der Stel (ex-Whelp) Vrystaat (ex-Wrangler)
Preceded by: Bay class Followed by: Type 16 frigates
List of frigates of the Royal Navy List of frigates of the Royal Australian Navy List of frigates of the Royal Canadian Navy