The Type 23 frigate is a warship class of the Royal Navy also known as the Duke class. Sixteen of this class have been built, with the final vessel, HMS St Albans (F83) launched in May 2000.

The frigate was initially designed as a light anti-submarine warfare platform, with a Lynx or EH-101 Merlin active dipping sonar helicopter, to replace the frigates of the Leander class. The frigates, with no anti-air armament and which would operate primarily in the North Atlantic, would be resupplied by a large force of Fort class replenishment ships. These supply ships were to be fitted with the Sea Wolf missile system for protection of the frigates. Constraints on the navy and the experiences of the Falklands War led to a redesign of the frigates with the addition of a main gun, and a reduced radar signature. The frigate's role was further expanded to cover all forms of naval operations with the addition of Harpoon and Sea Wolf missile systems.

HMS Norfolk (F230) was the first of the class to enter service, commissioned on June 1, 1990 at a cost of £135.449 million. Later vessels cost £60-96 million. The annual costs of running a Type 23 is around £16 million.

On July 21 2004, in a review of defence spending, Defence Secretary Geoff Hoon announced HMS Norfolk, HMS Marlborough (F233) and HMS Grafton (F80) were to be paid off. Given that the oldest vessel is just over ten years old it seems likely that these would be sold.

Specifications:

Length: 133m (436.2ft) Beam: 16.1m (52.8ft) Displacement: 4,900 tonnes fl Crew: 185 Power: CODLAG (Combined Diesel, Electric and Gas). Two Rolls-Royce Spey 34,000hp (25MW) gas turbines; two Alstom 1.5MW electric motors. Speed: 28kts (52km/h) maximum. 12,500km at 15kts (28km/h) Weapons:

• 2 x quad Harpoon missile launchers
• VLS GWS 26 Mod 1 Sea Wolf SAM system
• 1-4.5in (114mm) Vickers Mk 8 gun (some ships being upgraded with the Mod 1)
• 2 x Oerlikon 20mm guns
• 4 Cray Marine 324mm (2 Twin) TT. Marconi Stingray.
• NATO Seagnat, Type 182 and DLF3 decoy launchers

Aircraft: Lynx Mk 8 helicopter

• Armament:
  • Sea Skua missiles
  • Stingray torpedoes
  • depth charges

Sensors:

• Air/surface Search: Plessey Type 996, 3D
• Navigation: Kelvin Hughes Type 1007 or Racal Decca Type 1008
• Fire control: 2 Marconi Type 911
• Ferranti/Thompson-Sintra Type 2050 Sonar
• Dowty Type 2031Z to be replaced by Type 2087 2003

Ships

• HMS Norfolk (F230)
• HMS Argyll (F231)
• HMS Lancaster (F229)
• HMS Marlborough (F233)
• HMS Iron Duke (F234)
• HMS Monmouth (F235)
• HMS Montrose (F236)
• HMS Westminster (F237)
• HMS Northumberland (F238)
• HMS Richmond (F239)
• HMS Somersetl (F82)
• HMS Grafton (F80)
• HMS Sutherland (F81)
• HMS Kent (F78)
• HMS Portland (F79)
• HMS St Albans (F83)

Type 23 frigate

Norfolk | Argyll | Lancaster | Marlborough | Iron Duke | Monmouth | Montrose | Westminster | Northumberland | Richmond | Somerset | Grafton | Sutherland | Kent | Portland | St Albans

List of frigates of the Royal Navy