Type 31-class
Affordable British general-purpose frigate based on the Danish Iver Huitfeldt hull, exported to Indonesia and Poland.
| Subtype | General-purpose frigate |
| Displacement | 5700 tons |
| Crew | 110 members |
| Width | 19.8 m (65.0 ft) |
| Length | 138.7 m (455.1 ft) |
| Propulsion | CODAD: 4 × MAN diesels, 2 shafts |
| Units | Venturer, Active, Formidable, Bristol, Campbeltown |
| Range | 9000 km at 18 knots |
| Maximum speed | 28 knots |
- 12+ × Sea Ceptor (CAMM) air-defence missiles
- 1 × 57 mm Bofors Mk 110 gun
- 2 × 40 mm Bofors Mk 4 guns
- Fitted for Mk 41 VLS
- 1 × Wildcat or Merlin helicopter
Description
The Type 31, or Inspiration class, is the Royal Navy's affordable general-purpose frigate, procured under the National Shipbuilding Strategy at a headline price of £250-268 million per ship — a fraction of the cost of a Type 26. Five ships are being assembled by Babcock at Rosyth to replace the general-purpose Type 23s, with the first, HMS Venturer, launched in 2024 and the class entering service from around 2027.
The design is based on Babcock's Arrowhead 140, itself derived from the proven Danish Iver Huitfeldt-class hull, giving a large 5,700-ton, 138.7-meter platform with a speed above 28 knots and a range of 9,000 nautical miles at 18 knots with a lean crew of about 110. The UK fit is deliberately modest — a 57 mm Bofors Mk 110 main gun, two 40 mm Bofors Mk 4s and Sea Ceptor air-defence missiles — but the hull has space and weight margins for a Mk 41 VLS and heavier armament, and a flight deck and hangar for a Wildcat or Merlin.
The Arrowhead 140 design has also been exported: Indonesia ordered two ships as the Merah Putih class and Poland is building three as the Wicher (Miecznik) class with a heavier combat system, validating the programme's export ambitions. The five Royal Navy ships carry names evoking famous predecessors: Venturer, Active, Formidable, Bristol and Campbeltown.