The Armstrong Siddeley Snarler was a small rocket engine used for mixed-power experiments with an early turbojet engine.[1][2] and was the first British liquid-fuelled rocket engine to fly.[3]
Design and development
Unlike other British rocket engine projects that used hydrogen peroxide as an oxidiser, Armstrong Siddeley's used liquid oxygen. The rocket engine is described as having a dry weight of 215 lbf (960 N) thrust of 2,000 lbf (8.9 kN) and a specific fuel consumption of 20 (lb/h)/lbf thrust.[3] Work began in 1947 and the final configuration was first tested on 29 March 1950.[3]
The prototype of the Hawker P.1040 Sea Hawk, VP 401, had a Snarler rocket of 2,000 lbf thrust added in its tail. The Rolls-Royce Nene turbojet, of 5,200 lbf thrust, had a split tailpipe which exhausted either side of the fuselage. The combination was termed the Hawker P.1072.[4][5]
This gave approximately[6] 50% greater thrust, although with twenty times the fuel consumption.[3] It was first used in flight on 20 November 1950, by Hawker's test pilotTrevor "Wimpy" Wade.[4] Half a dozen flights were made using the rocket motor before a minor explosion damaged the aircraft. Although methanol was used in the P.1072, jet fuel could be used for the Snarler. It was decided that reheat was a more practical proposition for boosting jet thrust than rockets.
An unusual feature of the engine was that the fuel/oxidiser pump was externally driven, by a drive from the gearbox of the P.1072's turbojet engine. This feature continued into the first versions of the subsequent Screamer engine, but was later replaced with a turbine-driven turbopump.[7]
^"The Quest for Power..."Flight: 444. 6 August 1954. Transferring liquid oxygen from a B.O.C. spherical tanker to the Hawker P.1072 in which the Sn rocket was tested. The gas is exhausting through the lower vents and rapidly evaporating.
^Although the Nene's thrust, as for any turbojet, fell with increasing altitude the Snarler's remained constant.