While the Royal Navy abandoned the idea of large scale coastal forces in 1957, it maintained a small force of three boats, the Coastal Forces Trials and Special Service Squadron, to maintain proficiency in operations of fast patrol boats if the need arose in the future, and to act as targets for training the fleet in tactics against hostile fast patrol boats. The force consisted of the only two s to be completed along with one boat.
In January 1969, an order was placed with Vosper Thornycroft for three fast training boats to replace the Braves and remaining Dark-class boats in the training role. The design chosen was a smaller derivative of the Brave-class design.[1]
The ships were 100inchesft0inchesin (ftin) long between perpendiculars and about 106inchesft0inchesin (ftin) overall, with a beam of 26inchesft8inchesin (ftin) and a draught of 6inchesft5inchesin (ftin). The ships' hulls were of laminated wood construction.[1] A transom flap was fitted to the ship's stern to improve speed and trim at high speed. Displacement was 80LT normal and 102LT deep load. Propulsion was by two Rolls-Royce Proteus gas turbine engines rated at a total of 8500shp and two Foden diesel engines rated at 240bhp arranged in a combined diesel and gas (CODAG) arrangement and driving two propeller shafts. This gave a maximum speed of 40kn. They had a range of 425nmi at or at . Complement was two officers and ten ratings.
The ships were unarmed, but were designed so that a gun or missile armament could be fitted if needed, while a third Proteus could be added for improved speed.[1]
The three boats were built at Vosper Thornycroft's Portchester yard from 1969 to 1971. Once initial teething problems associated with the settings for the transom flap were resolved, the boats met performance requirements. They served in the training role at Portland, with one boat (Scimitar) being sent to Hong Kong in 1979 for patrol duties, helping to intercept Vietnamese boat people and other migrants arriving by sea.[2] The three boats were laid up ashore and put on the disposal list in 1981,[1] and were later sold to Greek buyers.[1] Scimitar has since been transformed in a floating restaurant, currently anchored in the port of Fano, Italy. It has been heavily modified and the only original part of the ship that has been preserved is the hull.
| Name | Number | Launched | Commissioned | |
|---|---|---|---|---|
| Scimitar | P 271 | 4 December 1969 | 19 July 1970 | |
| Cutlass | P 274 | 19 February 1970 | 12 November 1970 | |
| Sabre | P 275 | 21 April 1970 | 5 March 1971 |