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Rolls-Royce Engines: Avon

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Avon. Exhibit at the National Museum of Flight.
Avon 28R. Exhibit at the Fleet Air Arm Museum.
1953. RA 14.
1954. RA14.
1956. Avon's in the Saab: 35.

Note: This is a sub-section of Rolls-Royce.

The Avon was Rolls-Royce' first axial flow jet engine.


Introduced in 1950, it went on to become one of their most successful post-World War II engine designs. It was used in a wide variety of aircraft, both military and civilian, ending production after 24 years in 1974.

The Avon design team was headed by A. Cyril Lovesey, who had previously been in charge of Merlin development. The engine was intended both as an experiment in axial-flow engines, as well as a replacement for the 5,000 lbf (22 kN) Nene. Originally known as the AJ.65 for Axial Jet, 6,500 lbf which was designed by Alan Arnold Griffith, the engine developed as a single-spool design with a 8, later 10 stage compressor, mass flow rate of 150 lb/s (68 kg/s) and a pressure ratio of 7.45. Development started in 1945 and the first prototypes were built in 1947. Introduction was somewhat slowed by a number of minor problems.

The engine entered production in 1950, the original RA.3/Mk.101 version providing 6,500 lbf (29 kN) thrust in the English Electric Canberra B.2. Similar versions were used in the Canberra B.6, Hawker Hunter and Supermarine Swift.

Uprated versions soon followed, the RA.7/Mk.114 producing 7,350 lbf in the de Havilland Comet C.2, the RA.14/Mk.201 of 9,500 lbf (42 kN) in the Vickers Valiant and the RA.26 of 10,000 lbf (44 kN) used in the Comet C.3, Sud Aviation Caravelle, and Hawker Hunter F.6. An Avon-powered de Havilland Comet 4 flew the first scheduled transatlantic jet service in 1958.

The line eventually topped out with the 12,690 lbf (56,450 N) and 16,360 lbf (72,770 N) in afterburner RA.29 Mk.301/2 (RB.146) used in later versions of the English Electric Lightning. Other aircraft to use the Avon included the de Havilland Sea Vixen and Fairey Delta.

The Avon was also produced under license by Svenska Flygmotor, the RA.3/Mk.109 as the RM5, and an uprated RA.29 as the RM6 with 17,110 lbf (76,110 N). The RM5 powered the Saab Lansen, while the RM6 was the main power plant of the SAAB Draken.

In the US, the Avon was used to power the vertical landing Ryan X-13 Vertijet aircraft (in RA.28-49 form) and the Martin B-57 (a license built development of the Canberra).

In Australia, the Avon was used by Commonwealth Aircraft Corporation to power its heavily modified variant of the F-86 Sabre, known as the CA-27 Avon-Sabre.

The Avon continued production, mostly for the use in the Sud Aviation Caravelle and English Electric (BAC) Lightning, until 1974, by which time over 11,000 had been built. The engine garnered an impressive safety record over that time. The Avon was still in operational service with the RAF in the Canberra PR.9 until 23 June 2006.


There were many industrial versions of the Avon made at the RR East Kilbride factory for use in gas turbine peak lopper electical generation plant. Typically, an English Electric peak lopping set would comprise two Avons driving a free power turbine that drove a 17MW turbo-alternator. In a 1960s coal fired power station with 4 off 500MW steam tubines main generators there would also be 4 Avon powered 17MW peak lopping generators.

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