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The Gloster Meteor was the first British jet aircraft to enter active service, and only the second jet aircraft of any nation to achieve that status. Work on the Meteor began in 1940, before the first flight of the Gloster E.28/39, the first British jet aircraft. The engines under development at the time were not powerful enough to allow the construction of a worthwhile single engined fighter, and so work had to begin on a twin engined aircraft. Early work on the new design continued throughout 1940, and by the start of 1941 was Gloster’s highest priority. The F.9/40 specification itself was issued in November 1940. This was followed by an order for twelve prototypes on 14 February 1941, of which eight were eventually built, and by an order for 300 Meteor F Mk.Is, which was confirmed on 8 August 1941.
The Engine
The most troublesome component of the Meteor was always going to be the jet engines themselves. In theory the turbojet engine is a simple device, with four main components and only two major moving parts.
Perhaps somewhat misleadingly, the components in a standard gas turbine jet engine are physically arranged out of their operating sequence, with the compressor at the front, then the combustion chamber, the turbine and the jet tube.
The operating sequence of the engine begins in the combustion chamber, where aviation fuel is mixed with air and then ignited to create a stream of fluid (this can refer to water, steam or gas – here it refers to the stream of gas leaving the combustion chamber).
This stream of gas is used to power the turbine, passing through a series of fan blades, causing them to rotate. The power this produces is then passed forward to the compressor, which sucks air in from the atmosphere. This is the air that is mixed with the fuel to create the stream of fluid. Having passed through the turbine, that stream of hot, high pressure air then passes through the final component, the jet tube, emerging from the rear of the engine at high speed. It is this stream (or jet) of high pressure air, moving at very high speeds, that provides the thrust that moves the aircraft.
The jet engine also needs two ignition systems. The combustion chamber will not provide enough power to operate the turbine unless the compressor is already running fast enough to provide the required amount of air, and so a separate starter motor is needed to operator the compressor until it is moving fast enough to force enough air into the combustion chamber to operate the turbine. A variety of different types of starter motors are used on modern jet engines, including simple electric motors, turbines powered by cordite charges, compressed air, or even a smaller gas turbine. The second system is used to ignite the air/fuel mix. Each jet engine will then reach a point where enough air is being provided by the compressor to make the process self-sustaining. At this point the first starter motor can be turned off.
Although the theory is simple, physical implementation is difficult. The main problem is heat. As the air passes through the compressor, the temperature rises. This is before it reaches the combustion chamber, where the temperatures rise once again. This very hot mix of air and ignited aviation fuel then passes through the turbine and the jet tube, so both of those components have to be able to withstand these very high temperatures. A second problem is caused by the high speeds at which the compressor and turbines operate. Even with modern materials the blades on the turbine tend to get longer and thinner over time, giving them a finite lifespan. The main problem facing the early jet pioneers was how to produce an engine that could provide a useable amount of thrust without getting too hot – in the worst cases the turbine blades could actually melt in the heat!
Five different engines would be considered during the development of the Meteor. Three were based on Frank Whittle’s own design, the W.2. The first of these was the W.2B/23, originally built and developed by Whittle and Rover until early 1943, and then by Whittle and Rolls-Royce. This would eventually be the basis of the W.2B/23 Welland engine, used in the Meteor I. Second was the Rolls-Royce W.2B/37, which would become the basis of the Derwent I engine used in the Meteor III. Finally a Power Jets W.2/500 engine would be used to power one of the prototypes.
The other two engines came from outside sources. Both would be used to power Meteor prototypes and both designs would eventually be successful, but neither would power production Meteors. The clossest was the de Havilland Halford H.1, which would power the DG207 prototype, the first of the Meteors to take to the air. This was similar to the Whittle engine, but used a single sided impeller instead of the double entry type used on the W.2. Despite this early success, only one Meteor II was built using the H.1 engine, which was reserved for de Havilland’s own jet aircraft.
The final engine used was the MetroVick F.2, built by Metropolitan-Vickers to a design from the Royal Aircraft Establishment. While the W.2 and H.1 both used centrifugal compressors, which were simple but less efficient, the MetroVick F.2 used an axial compressor. This was more complex but also more efficient and was used by the main German jet engines. Both types are still in use in modern engines. The MetroVick powered DG204 would be the fifth Meteor prototype to take to the air, on 13 November 1943, but it was destroyed in a crash on 4 January 1945, and would remain the only MetroVick powered Meteor. The F.2 engine itself went on to be the basis of the Armstrong-Siddleley F2/4 Beryl and then the F.9 Sapphire, which was used to power a number of post-war aircraft, amongst them the Gloster Javelin and the Hawker Hunter.
The problems with the W.2B engine came close to causing the cancellation of the entire project. By the summer of 1942 the first prototype was ready for ground running tests and taxiing trials, which got underway in September 1942, but the W.2B still didn’t provide enough power for flight. The delays were so serious that the first order for 300 Meteor F Mk.Is was reduced to only twenty aircraft. Finally, on 12 June 1943 the first W.2B powered aircraft, Meteor DG205, made its maiden flight, with Micheal Daunt at the controls. At this stage he was not impressed, and the eventual performance of the Meteor I was not a dramatic improvement on the best piston engined aircraft of the era. However, by now Rolls-Royce had taken over from Rover as Whittle’s main development partner, and their W.2B/37 engine, capable of providing 2,000lb of thrust, would be used to power the Meteor F Mk.III, the best of the wartime variants.
The Aircraft
While work on the engine progressed slowly, the design of the Meteor itself made rapid progress. Apart from its jet engines, the Meteor was actually a rather conventional aircraft for its period. Its thick straight wings would prove to be a particular disadvantage, causing problems with compressibility that limited its top speed, while its manually operated controls would make it tiring to manoeuvre – later jet aircraft would need power operated controls. The key advantage of this conventional construction was speed of development. At no point would work on one of the Meteor prototypes be delayed by problems with the fuselage or wings.
The Meteor was designed by George Carter, Gloster’s chief designer, and the man who had designed the E.28/39. The aircraft was built in five main sections. The fuselage itself was made up of three sections – the front section, complete with the nose wing, the central section, which included the main landing gear and the engine nacelles and the rear fuselage with the tail. Finally the two outer wing panels were attached to the engine nacelles.
Work on the cockpit, fuselage and a full wing mock-up was well underway by the middle of January 1941. By June 1942 the first prototype was almost complete, and was ready to begin ground running tests, with two more already under construction. The basic design of the Meteor would prove to be more flexible than expected, and would play a large part in the long lifespan of the meteor. The outer wing panels, nose and tail assemblies would all be replaced over the twenty year lifespan of the Meteor, and the aircraft would prove to be an excellent test bed for future engine research.
Coming together
The first of the prototypes to take to the air was DG207, powered by the de Havilland H.1 engine. This aircraft made its first flight on 5 March 1943 (see below), and for a time had the highest development priority, but it was soon decided to reserve the H.1 engine for the de Havilland Vampire. By the end of 1944 the H.1 powered Meteor had lost its high priority, and in August 1944 the project was delayed indefinitely. Only one more H.1 powered aircraft, the prototype and only Meteor F Mk.II, would fly.
After all of the delays, the W.2B/23 engine finally reached a point where it provided an acceptable level of power. The second Meteor to fly was the DG205, powered by two Rover W.2B engines, making its first flight on 12 June 1943. It was followed by a second W.2B/23 powered aircraft, the DG202, on 24 July 1943. This engine was then ordered into production as the Rolls-Royce Welland I, and was used to power the Meteor F Mk.I. The first prototype for that aircraft made its maiden flight on 12 January 1944, but only twenty would be built before production moved on to the Meteor F Mk.III.
The W.2B/37 was Rolls-Royce’s improved version of the Rover B.26 “straight-through” engine. It was installed in the eighth prototype, DG209, which made its maiden flight on 18 April 1944. This engine would become the Derwent I, and went on to power the Meteor F Mk.III, the ultimate wartime version of the aircraft.
The First Flight
Preparations for the first flight of Meteor DG206 began on 12 February 1943, when the aircraft was moved by road to RAF Cranwell. Taxi trials began on 3 March 1943, using engines de-rated to 2,000lb of thrust. Finally, on 5 March 1943, with Michael Daunt at the controls, the Meteor made its maiden flight. Rather disappointingly, this flight only lasted for three and a half minutes. As the aircraft gained speed, it became to yaw violently from side to side. Daunt was forced to slow down until the movement stopped and land as soon as possible. The problem was traced to a problem with the rudder, which was soon fixed. The second flight, made at Newmarket on 17 April 1943 was much more successful.
Gloster Meteor, Britain's Celebrated First-Generation Jet, Phil Butler and Tony Buttler. This is a detailed, well illustrated and well written look at the development and service history of the Gloster Meteor, both in British and overseas hands. The book covers the development of the E.28/39, Britain's first jet aircraft and the development of the Meteor, looks in detail at the prototype aircraft, the various versions of the Meteor and its British and overseas service careers. [see more]
