Type 23 frigate

	HMS Sutherland in December 2012
Class overview
Name	Type 23 frigate
Builders	Yarrow Shipbuilders and Swan Hunter
Operators	Royal Navy; Chilean Navy;
Preceded by	Type 22-class frigate
Succeeded by	Type 26-class frigate ; Type 31-class frigate;
Cost	£130 million per ship
In commission	24 November 1987
Planned	16
Completed	16
Active	5 Royal Navy, 3 Chilean Navy
Retired	8 (Royal Navy)
General characteristics
Type	Anti-submarine warfare frigate
Displacement	4,900 t (4,800 long tons)
Length	133.0 m (436 ft 4 in)
Beam	16.1 m (52 ft 10 in)
Draught	7.3 m (23 ft 11 in)
Propulsion	CODLAG:; 4 × 1,510 kW (2,025 hp) Paxman Valenta 12CM diesel generators (Non-PGMU ships); 4 × 1,650 kW (2,210 shp) MTU 12V4000 M53 diesel generators (PGMU ships); 2 × GEC electric motors delivering 2,980 kW (3,996 hp) each; 2 × Rolls-Royce Marine Spey SM1C delivering 19,500 kW (26,150 hp);
Speed	In excess of 28 knots (52 km/h; 32 mph)
Range	7,500 nmi (14,000 km; 9,000 mi) at 15 kn (28 km/h; 17 mph)
Boats & landing; craft carried	2 × Pacific 24 RIBs
Complement	185 (accommodation for up to 205)
Electronic warfare; & decoys	UAT Mod 1; Seagnat; Type 182 towed torpedo decoy; Surface Ship Torpedo Defence;
Armament	Anti-air missiles:; 1 × 32-cell Sea Ceptor GWS 35 Vertical Launching System (VLS) canisters for 32 missiles (1–25+ km) (replaced original Sea Wolf SAM) ; Anti-ship missiles:; 2 × quad Harpoon Block 1C (originally fit, retired from most ships 2023, retained on F229 as of late 2024); being replaced by Naval Strike Missile (fit to F79, F82 & F239 as of early 2025); Anti-submarine torpedoes:; 2 × twin 12.75 in (324 mm) Sting Ray torpedo tubes; Guns:; 1 × BAE 4.5-inch Mk 8 naval gun; 2 × 30 mm DS30M Mk2 guns, or, 2 × 30 mm DS30B guns; 2 × Miniguns (replaced by Browning .50 caliber heavy machine guns as of 2023); 4 × General-purpose machine guns;
Aircraft carried	1 × Wildcat HMA2, armed with:; 2 × anti-submarine torpedoes or Martlet anti-ship (ASM)/air-to-air missiles, initially deployed with RN carrier strike group helicopters in 2021; Sea Venom ASM reached initial operating capability in 2025 and is projected to achieve full operational capability in 2026.; or; 1 × Westland Merlin HM2, armed with;; 4 × anti-submarine torpedoes; Plus; 2 x Peregrine ISR UAV (from mid-2024 on F229);
Aviation facilities	Flight deck; Enclosed hangar;

The Type 23 frigate or Duke class is a class of frigates built for the United Kingdom's Royal Navy. The ships are named after British Dukes, thus leading to the class being commonly known as the Duke class. The first Type 23, HMS Norfolk, was commissioned in 1989, and the sixteenth, HMS St Albans was commissioned in June 2002. They form the core of the Royal Navy's destroyer and frigate fleet and serve alongside the Type 45-class destroyers. They were designed for anti-submarine warfare, but have seen a range of duties. Five Type 23 frigates remain in service with the Royal Navy, with three vessels having been sold to the Chilean Navy and eight being retired since 2021.

In 2019, The Royal Navy announced that the Type 23 frigates would be replaced by the Type 26-class frigate and the Type 31-class frigate. As of 2021 it is anticipated that HMS St Albans will be the last to retire from the Royal Navy, in 2035.