Rolls-Royce Avon

The Avon was Rolls-Royce's 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.

Design and development

The Avon design team was headed by 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 (if successful) 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 an 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.

Early Marks had 8 canular combustion chambers whereas later Marks had a can-annular combustion chamber and a 15 stage compressor.

Production

The engine eventually 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 powerplant 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.

Other uses

* The Avon is also currently marketed as a compact, high reliability, stationary power source. As the AVON 1533, it has a maximum continuous output of 21,480 shp (16.02 MW) at 7,900 rpm and a thermal efficiency of 30%. In 1982, an Avon engine on gas pumping duty in a Canadian installation ran for 53,000 hours before requiring a major overhaul. In 1994, another industrial Avon engine ran non-stop for 476 days (11,424 hrs).
* As a compact electrical generator, the type EAS1 Avon based generator can generate a continuous output of 14.9 MW.
* On October 4 1983, Richard Noble's Thrust2 vehicle, powered by a single Rolls-Royce Avon 302 jet engine, set a new land-speed record of 1,019.46 km/h (633.46 mph) at the Black Rock Desert in Nevada.

pecifications (Avon 301R)

Data from: [cite web| url=http://www.lightning.org.uk/techdata.html |title =Lightning F.6 Avon 301R Specs |publisher =www.lightning.org.uk] jetspecs

type=Turbojet
length=
diameter=
weight=2,890 lbs (1,309 kg)
compressor=15-stage axial flow
combustion=150 lbs/sec
turbine=Two-stage axial flow
fueltype=
oilsystem=
power=
thrust=12,690 lb (56.45 KN) dry / 16,360 lb (72.77 KN) with reheat
compression=7.45
aircon=
turbinetemp=
fuelcon=
specfuelcon=0.932 lb/lbf h (dry) 1.853 lb/lbf h (wet) [ [http://www.jet-engine.net/miltfspec.html Avon RB.146 Mk.301] ]
power/weight=
thrust/weight=5.66:1 (56 N/kg)

Applications

Military aviation

#CA-27 Avon-Sabre fighter
#de Havilland Sea Vixen fighter
#English Electric Canberra bomber
#English Electric Lightning interceptor
#Fairey Delta high-speed research aircraft
#Hawker Hunter fighter bomber
#Martin B-57 bomber
#Ryan X-13 Vertijet research aircraft
#SAAB Draken fighter
#Saab Lansen fighter
#Supermarine Swift fighter
#Vickers Valiant bomber

Civil aviation

#de Havilland Comet airliner
#Sud Aviation Caravelle airliner

ee also

* Metrovick F.2 - UKs first axial flow design
* Rolls-Royce plc
* List of aircraft engines

References

External links

* [http://www.wingweb.co.uk/engines/Rolls-Royce_Avon_turbojet.html The fascinating story of the Rolls Royce Avon turbojet engine, the first Rolls Royce axial flow turbojet]
* [http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=882 National Museum of USAF - AVON MK 203 TURBOJET]
* [http://www.shanaberger.com/engines/avon.htm Rolls-Royce Avon]