| Ashton | |
|---|---|
 | |
| Avro Ashton prototype | |
| Role | Experimental airliner |
| Manufacturer | Avro |
| First flight | 1 September 1950 |
| Number built | 6 |
| Developed from | Avro Tudor |
The Avro 706 Ashton was a British prototype jet airliner made by Avro during the 1950s. Although it flew nearly a year after the de Havilland Comet, it represented an experimental programme and was never intended for commercial use.
The Avro 689 Tudor 9 was based on the Avro 689 Tudor II piston-engined airliner using experience on work on the Rolls-Royce Nene jet-powered experimental variant, the Tudor 8, which made its first flight on 6 September 1948. [1] The Avro Type 689 Tudor 9, later renamed the Avro 706 Ashton, was a four-jet-engined research aeroplane powered by Rolls-Royce Nene engines paired in wing nacelles.
Six were built using the Tudor airframe, beginning with the conversion of Tudor I initially powered by Nene 5 engines. The Ashtons that followed incorporated the upgraded Nene 6 and featured an enlarged, "square-shaped" tail fin and tricycle landing gear replacing the original "taildragger" configuration. The engines were tightly grouped in two nacelles that were faired neatly into the wing but also extended below in streamlined pods. The four-engine arrangement compensated for the low thrust of the early jet engines and greatly reduced asymmetric effects in an "engine-out" scenario. [2]
The crew was composed of a pilot, co-pilot, navigator, flight engineer and radio operator clustered together in the cockpit and front compartment of the Ashton. A larger complement could be carried in the spacious fuselage when warranted.
Production was completed rapidly through modifications of surplus Tudor 2 airframes with a single example each of the Ashton 1 (WB490), Ashton 2 (WB491), Ashton 4 (WB494) and three Ashton 3s (WB492, WB493 and WE670), all built by Avro at Woodford. Test flights began in 1950 with evaluations of jet operations, navigation and at least one Ashton (Mk 4) tested bombing equipment with two streamlined underwing bomb containers fitted. [3]
Despite being one of the first jet-engined air transports, the Ashton was engaged in primarily experimental work and was soon eclipsed in technology by the first of the full-scale production airliners, the de Havilland Comet.
Ashton WB491 was modified with an under-fuselage mounting for testing turbine engines. It was used by Rolls-Royce for trials with the Conway and Avon.
Bristol Siddeley used Ashton WB493 as a testbed for its Olympus turbojet. The aircraft was fitted with two Olympus engines under the wings, outboard of the Nenes. This aircraft had a starring role in the 1960 British movie Cone of Silence , masquerading as the "Atlas Phoenix". Later the same aircraft was used as a test bed for the Bristol Siddeley Orpheus, its port engine having been upgraded to the Orpheus features for trials.
A piece of the fuselage of the Ashton 2 (WB491) is preserved at the Newark Air Museum, Winthorpe, UK.
Data fromJane's. [4]
General characteristics
Performance
Armament
Related development
Avro was a British aircraft manufacturer. Its designs include the Avro 504, used as a trainer in the First World War, the Avro Lancaster, one of the pre-eminent bombers of the Second World War, and the delta wing Avro Vulcan, a stalwart of the Cold War.
A jet airliner or jetliner is an airliner powered by jet engines. Airliners usually have two or four jet engines; three-engined designs were popular in the 1970s but are less common today. Airliners are commonly classified as either the large wide-body aircraft, medium narrow-body aircraft and smaller regional jet.
The Avro Canada C102 Jetliner was a Canadian prototype medium-range turbojet-powered jet airliner built by Avro Canada in 1949. It was beaten to the air by only 13 days by the de Havilland Comet, thereby becoming the second jet airliner in the world. The name "Jetliner" was chosen as a shortening of the term "jet airliner", a term which is still in popular usage. The aircraft was considered suitable for busy routes along the US eastern seaboard and garnered intense interest, notably from Howard Hughes who even offered to start production under license. However continued delays in Avro Canada's all-weather interceptor project, the CF-100 Canuck, led to an order to stop working on the project in 1951, with the prototype Jetliner later cut up for scrap.
The Rolls-Royce Olympus was the world's second two-spool axial-flow turbojet aircraft engine design, first run in May 1950 and preceded only by the Pratt & Whitney J57, first-run in January 1950. It is best known as the powerplant of the Avro Vulcan and later models in the Concorde SST.
The Rolls-Royce RB.37 Derwent is a 1940s British centrifugal compressor turbojet engine, the second Rolls-Royce jet engine to enter production. It was an improved version of the Rolls-Royce Welland, which itself was a renamed version of Frank Whittle's Power Jets W.2B. Rolls-Royce inherited the Derwent design from Rover when they took over their jet engine development in 1943.
Sir Stanley George Hooker, CBE, FRS, DPhil, BSc, FRAeS, MIMechE, FAAAS, was a mathematician and jet engine engineer. He was employed first at Rolls-Royce where he worked on the earliest designs such as the Welland and Derwent, and later at Bristol Aero Engines where he helped bring the troubled Proteus turboprop and the Olympus turbojet to market. He then designed the famous Pegasus vectored thrust turbofan used in the Hawker Siddeley Harrier.
The Bréguet Br 960 Vultur was a prototype two-seat carrier-based attack and anti-submarine aircraft (ASW) built for the French Navy during the early 1950s. Meeting contradictory endurance and speed requirements, it was designed as a "mixed-power" aircraft with a turboprop engine in the front and a turbojet in the rear. Only two examples were built, but the second aircraft was rebuilt as the prototype of the Bréguet 1050 Alizé ASW aircraft after the Navy dropped the idea of a turboprop attack aircraft in the mid-1950s.
The Hawker P.1072 was a 1949 experimental British aircraft acting as a test bed for the Armstrong Siddeley Snarler rocket booster engine. It was the prototype Hawker Sea Hawk modified to install the rocket in the tail.
The Short SA.4 Sperrin was a British jet bomber design of the early 1950s, built by Short Brothers and Harland of Belfast. It first flew in 1951. From the onset, the design had been viewed as a fall-back option in case the more advanced strategic bomber aircraft, then in development to equip the Royal Air Force's nuclear-armed V bomber force, experienced delays; the Sperrin was not put into production because these swept-wing designs, such as the Vickers Valiant, were by then available.
The Avro Type 688 Tudor was a British piston-engined airliner based on Avro's four-engine Lincoln bomber, itself a descendant of the famous Lancaster heavy bomber, and was Britain's first pressurised airliner. Customers saw the aircraft as little more than a pressurised DC-4, and few orders were forthcoming, important customers preferring to buy US aircraft. The tailwheel undercarriage layout was also dated and a disadvantage.
Cone of Silence is a 1960 British drama film directed by Charles Frend and starring Michael Craig, Peter Cushing, George Sanders, and Bernard Lee. The film is about the investigation into a series of crashes involving the fictional 'Atlas Aviation Phoenix' jetliner. Cone of Silence is based upon the novel of that name by David Beaty, which is loosely based on the 1952 crash in Rome and subsequent investigations into the structural integrity of the de Havilland Comet airliner.
The Tupolev Tu-12 was an experimental Soviet jet-powered medium bomber developed from the successful piston-engined Tupolev Tu-2 bomber after the end of World War II. It was designed as a transitional aircraft to familiarize Tupolev and the VVS with the issues involved with jet-engined bombers.
The Rolls-Royce/Snecma Olympus 593 was an Anglo-French turbojet with reheat (afterburners), which powered the supersonic airliner Concorde. It was initially a joint project between Bristol Siddeley Engines Limited (BSEL) and Snecma, derived from the Bristol Siddeley Olympus 22R engine. Rolls-Royce Limited acquired BSEL in 1966 during development of the engine, making BSEL the Bristol Engine Division of Rolls-Royce.
The SNCASE Grognard was designed as a single-seat, low-level ground-attack aircraft. Although in development in the 1950s for the French Armée de l'Air, the program was cancelled in favor of the Sud-Ouest Vautour II.
The SNCASO SO.4000 was an experimental French twin-engine bomber of the 1950s. It was the first French jet bomber developed, but it never entered operational service.
The Bristol Type 200 was a proposal for a short-range aircraft by the Bristol Aeroplane Company in 1956. Although it was designed in response to a specification issued by British European Airways (BEA), the Type 200 was larger than the airline's requirements and was closer to the Boeing 727 in size and range. The project was cancelled when BEA selected the Hawker Siddeley Trident instead. The Trident went on to have a production run of 117, while the 727 had a production run of over 1800. Along with the Vickers V-1000, it is seen by some as one of the great "what ifs" of British aviation, although it never got beyond the drawing board.
The Tupolev '73',, was a Soviet trijet medium bomber of the late 1940s. It lost out to the Ilyushin Il-28 'Beagle'.
The IA 36 Cóndor was a projected Argentine jet propelled mid-range airliner, designed in the early 1950s by Kurt Tank for the “Fábrica Militar de Aviones”. It was cancelled in 1958, with no prototypes built, but a full size wood mockup.
The Bristol Type 172 was a 1940s proposed British long range four-engined bomber project. Although work was carried out on designing experimental half-scale variants, none were built and the project was abandoned.
The Rolls-Royce Olympus turbojet engine was developed extensively throughout its production run, the many variants can be described as belonging to four main groups.
