Frank Whittle
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Sir Frank Whittle (June 1, 1907 - August 9, 1996) was a Royal Air Force officer who invented the jet engine. Due to funding and manufacturing problems, Hans von Ohain of Germany was able to beat him to production models, but Whittle's work and tireless efforts to produce his designs given official uninterest are legendary. After the war Whittle and Ohain became good friends.
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Early life
Whittle was born in Earlsdon, Coventry on June 1 1907, son of a mechanic. He left Leamington College in 1923 to join the RAF. Through his early days as an apprentice mechanic he maintained his interest in the Model Aircraft Society where he built replicas, the quality of which attracted the eye of his commanding officer, who also felt that Whittle was a mathematical genius.
He was so impressed that he recommended Whittle for the Officer Training College at Cranwell in Lincolnshire in 1926, a rarity for a "commoner" in what was still a very class-based military structure. Of the few apprentices that were accepted, only about one percent completed the course. For Whittle this was the chance of a lifetime, not only to enter the officer's corps, but also because the training included flying lessons. Whittle was the exception to the rule, graduating 1928 at the age of 21, ranked second in his class and a "Exceptional to Above Average" pilot.
Development of the jet engine
Another requirement of the course was that each student had to produce a thesis for graduation. Whittle decided to write his thesis on future developments in aircraft design, notably high-speed flight at high altitudes and speeds over 500mph. He showed that incremental improvements in existing propeller engines were unlikely to make such flight routine, and instead went on to describe an entirely new engine based on the gas turbine principle, using its exhaust for power. In addition to being useful at high altitudes, the engine essentially had one moving part, the compressor-drive shaft-turbine assembly. Reliability, weight and cost should all be lower for such a design.
In July 1926 A. A. Griffith published a paper on compressors and turbines, which he had been studying at the RAE. For aircraft use he considered only the axial compressor to be useful, due to its reduced frontal size. He showed that such designs up to this point had been flying "stalled", and that by making the compressor blades into an aerofoil shape, their efficiency could be dramatically improved. The paper went on to describe how the increased efficiency of these sorts of compressors and turbines would allow a jet engine to be produced, although he felt the idea was impractical and instead suggested using the power as a turboprop. At the time most superchargers used a centrifugal compressor, so there was limited interest in the paper.
Whittle's original thesis was published in 1929. He sent it to the Air Ministry to see if there would be any interest. With little knowledge of the topic they turned to the only other person who had written on the subject, and passed the paper on to Griffith. After pointing out an error in one of the calculations, he went on to comment that the centrifugal design would be too large for aircraft use, and that using the jet directly for power would be rather ineffecient. The RAF returned comment to Whittle, where they referred to the design as impracticable.
Others in the RAF were not so sure, and in particular Johnny Johnson convinced him to patent the idea in 1930. Since the RAF was not interested in the concept they did not declare it secret, which meant that Whittle was able to retain the rights to the idea, which would have otherwise been the property of the RAF. This rejection would later turn out to be a major stroke of luck.
Meanwhile Whittle moved onto the Officers' Engineering Course at RAF Henlow, Bedfordshire in 1932, and then to Peterhouse, Cambridge in 1934, graduating in 1936 with a First in the Mechanical Sciences Tripos.
Power jets
Whittle's patent lapsed in 1935 because he could not afford the renewal fee of £5. But soon after this he was approached by ex-RAF men, Rolf Dudley-Williams and J. Tinling to expand the development of his engine. The three incorporated as Power Jets Ltd in 1936 with a bank loan of £2,000, and work was started on an experimental engine at a British Thomson-Houston (BTH) (a steam turbine company) factory in Rugby, Warwickshire. The RAF still saw no value in the effort, and although Whittle was still a pilot they agreed to allow him to work on the design as long as it took no more than 6 hours a week.
Funding development of the first engine, known as the WU (Whittle-Union) was a serious problem. Although privately funded, most potential investors shied from a project that appeared to be semi-secret yet had no RAE backing. Something seemed to be a amiss, if the project was going to work, why didn't the RAE fund it? Once again it seemed not everyone was so unconvinced of Whittle's ideas, and in October 1936 Henry Tizard, the rector of Imperial College and chairman of the Aeronautical Research Committee, sent details of Whittle's engine to Griffiths once again. Griffiths had by this time started construction of his own design; perhaps in order to avoid tainting his own efforts, he returned a much more positive review. He remained highly critical of some features, seemingly ignoring the fact that its performance at high speed at height was the crucial aspect of the programme.
Even with these problems Power Jets were able to complete the WU, which ran successfully on April 12th, 1937. Now somewhat more interested, the Air Ministry immediately signed a contract for £6,000 to develop a flyable version. Meanwhile testing continued with the WU, which showed an alarming tendency to race out of control. Due to the dangerous nature of the work being carried out, in 1938 development was largely moved from Rugby to the BTH's semi-disused Ladywood foundry at nearby Lutterworth in Leicestershire. There was a successful run there in March 1938. Although the potential of the engine was obvious, the Air Ministry remained focused on the practical issues of gearing up production of existing piston engine designs.
All of these delays and the lack of funding had seriously delayed the project. In Germany, Hans von Ohain had started work on a prototype in 1935 and had already passed the prototype stage and was building the first flyable design, the Hirth He.S 3. There is little reason to believe that Whittle's efforts would have been at the same level had the Air Ministry taken a greater interest in the efforts. When the war started, Power Jets had a payroll of only 10, and Griffith's efforts, at Metropolitan Vickers, were similarly small.
Following the outbreak of World War II the Air Ministry changed priorities and once again looked at the various advanced projects underway. By 1939 the company could barely afford to keep the lights on when yet another visit was made by Air Ministry personel. This time Whittle was able to run the WU at high power for 20 minutes without any difficultly. One of the members of the team was the Director of Scientific Research, H. E. Wimperis, who walked out the demonstration utterly convinced of the importance of the project. A contract for full-scale development was immediately sent to Power Jets, along with a number of tenders to various companies to set up production lines for up to 3,000 engines a month in 1942.
Whittle had already studied the problem of turning the massive WU into a flyable design, and work started on the Whittle Supercharger Type W.1. A prototype, the W.1X, ran for the first time on 14 December 14th, 1940. The "full" W.1 of 3.8 kN thrust ran on April 12th, 1941. Gloster's experimental airframe was already complete by this point, and on May 15, 1941 the W.1-powered Gloster E. 28/39 took off from Cranwell at 7.40 pm, flying for seventeen minutes and reaching a maximum speed of around 545 km/h. Within days it was reaching 600 km/h at 7600 meters, exceeding the performance of the contemporary Spitfires, astounding considering this was the very first such engine. Success of the design was now evident to all, and nearly every engine company in England started their own crash efforts to catch up with Power Jets.
A newer design known as the W.2 was then started. Like the W1 it featured a unique "reverse flow" design of the burners, in which the heated air from the flame cans was piped back towards the front of the engine before entering the turbine area. This allowed the engine to be "folded", with the flame cans lying around the turbine area, and therefore making for a shorter engine. The Air Ministry was eager to obtain an operational jet aircraft, and authorised BTH to press ahead with a twin-engined jet interceptor, which would evolve into the Gloster Meteor. The Meteor was intended to use either the W2 or the similar Halford H1 (later named Goblin) but deHavilland later decided to keep all the Halford's for their own design, the de Havilland Vampire.
Rover
Power Jets had no real manufacturing capability, so the Air Ministry offered shared production and development contracts to BTH, Vauxhall and Rover. However, the contract was eventually taken up by Rover only. Rover set up a new laboratory and production line in 1941 at their Barnoldswick factory, but they also set up a parallel effort with their own engineers at Waterloo Mill, Clitheroe. Here Adrian Lombard attempted to develop the W2 into a production quality design, dispensing with Whittle's "reverse flow" burners and develop a "straight-through" engine instead. While work at Barnoldswick continued on Whittle's originally design, now known as the W.2B/23, Lombard's new design became the W.2B/26. This change angered Whittle.
By late 1941 it was obvious to all that the arrangement was not working; Whittle was frustrated by Rover's inability to deliver production-quality parts, along with their "we know better than you" attitude, and became increasingly vocal about his complaints. Likewise Rover was losing interest in the project after the delays and constant harrassment from Power Jets.
Rolls-Royce
Earlier, in 1940, Stanley Hooker of Rolls-Royce had met with Whittle, and later introduced him to Rolls' CEO, Ernest Hives. Rolls had a fully developed supercharger division, which Hooker directed, which was naturally suited to jet engine work. Hives agreed to supply key parts to help the project, and it was Rolls engineers who helped solve the surging problems seen in the early engines. In early 1942 Whittle contracted Rolls for six engines as well, known as the WR.1, identical to the existing W.1.
The problems with Rover became a "public secret", and eventually Spencer Wilkes of Rover met with Hives and Hooker at the Swan and Royal pub near the Barnoldswick factory. They decided to trade the jet factory at Barnoldswick for Rolls' tank engine factory in Nottingham. A handshake sealed the deal. The handover took place on 1 January 1943, although the offical date was later. Rolls soon closed Rover's "parallel" plant at Clitheroe, although they continued development of the W.2B/26 that had been developed there.
Testing and production was immediately stepped up. In December Rover had tested the W.2B for a total of 37 hours, only a month later Rolls-Royce tested it for 390 hours. The W.2B passed its first 100 h test at full performance of 725 kg on 7 May 1943. The prototype Meteor airframe was already completed, and took to the air on 12 June 1943. Production versions started rolling off the line in October, first known as the W.2B/23, then the RB.23 (for Rolls-Barnoldswick), and eventually the Rolls-Royce Welland. Barnoldswick was too small for full-scale production and turned back into a pure research facility under Hooker, while a new factory was set up in Newcastle-under-Lyme. The W.2B/26, as the Rolls-Royce Derwent, opened the new line and soon replaced the Welland, allowing the production lines at Barnoldswick to shut down in late 1944.
With the W.2 now proceeding smoothly, Whittle was sent to Boston in mid-1942 to help the General Electric jet programme. GE, the primary supplier of turbochargers in the US, was well suited to quickly bringing jet production online. A combination of the W.2B design and a simple airframe from Bell Aircraft flew in autumn of 1942 as the Bell XP-59A Airacomet.
Whittle's developments at Power Jets continued, resulting in the improved W.2/500, and later the W.2/700. Rolls nevertheless proceeded with their own designs. With every engine company now producing their own designs and Whittle's own not being purchased for production, Power Jets was no longer able to generate realistic income. In April 1944 Power Jets was nationalized, becoming the National Gas Turbine Establishment at the original Ladywood experimental site. Whittle, disenfranchized, quit in 1948 and eventually moved to the US.
Whittle's work had caused a minor revolution within the British engine manufacturing industry, and even before the E.28/39 flew most companies had set up their own research efforts. In 1939 Metropolitan-Vickers set up a project to develop an axial-flow design as a turboprop, but later re-engineered the design as a pure jet known as the Metrovick F.2 Beryl. Rolls-Royce had already copied the W.1 to produce the low-rated WR.1, but later stopped work on this project after taking over Rover's efforts. de Havilland started a jet fighter project in 1941, the Spidercrab - later called Vampire - along with their own engine to power it, Frank Halford's Goblin (Halford H1) a modified version of Lombard's straight-through W.2B. Armstrong Whitworth also developed an axial-flow design, the ASX, but reversed Vicker's thinking and later modified it into a turboprop instead, the Python.
Although the Luftwaffe beat the British efforts by a few weeks, largely due to the delays at Rover, Whittle's efforts were nevertheless far more influential. The engines that powered the Meteor were far more reliable than their German counterparts, which would typically last 10 hours or less, and sometimes exploded on their first startup. The equivalent British engine would run for 150 hours between overhauls and had twice the power-to-weight ratio and half the specific fuel consumption. By the end of the war every major engine company in Britain was working on jet designs, and practically every other design in the world was based on the Whittle pattern, or licensed outright. It was not until the late-1950s that engines powering US and USSR fighters were no longer directly related to the original Whittle work.
Later life
Frank Whittle retired from the RAF with the rank of Air Commodore in 1948 and was made a Knight of the Order of the British Empire (KBE) in that same year. He became a technical advisor to BOAC, emigrated to the USA in 1976 and was a Professor at the U.S. Naval Academy, Annapolis, Maryland. He died in Baltimore.
Frank Whittle married Dorothy Lee in May 1930 and they had two sons. Whilst at Cranwell he lodged in a bungalow at Dorrington. The marriage was dissolved in 1976 and Whittle re-married, to Hazel Hall.
Memorials
Whittle has several memorials, these include:
- A full scale model of the E.28/39 Whittle has been erected just outside the northern boundary of Farnborough airfield in Hampshire, England.
- A similar memorial has been erected in the middle of a roundabout outside Lutterworth where much of Whittle's development was carried out.
- In Whittle's birthplace Coventry, he is commemorated by the "Whittle Arch" a wing-like structure outside the Coventry Transport Museum.
- The Sir Frank Whittle Medal is awarded annually by the Royal Academy of Engineering.
External link
- Memorial for University of Cambridge Student (http://www.admin.cam.ac.uk/news/press/dpp/2004010801) who Invented The Jet Engine
- More about Frank Whittle (http://www-g.eng.cam.ac.uk/125/achievements/whittle/telgraph.htm).
- More about Frank Whittle and the jet age (http://www.raf.mod.uk/history/e281.html) at the 'Royal Air Force History' website.