An Early Purpose-Built Gas Turbine Research And
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AN EARLY PURPOSE-BUILT GAS TURBINE RESEARCH AND DEVELOPMENT ESTABLISHMENT by DAVID W. LYNE Summary: In 1941 the rapidly developing Power Jets Company, formed to exploit Frank Whittle's gas turbine patents moved to a site at Whetstone in Leicestershire. This article outlines the history and development of the company and describes the form and function of those buildings built during the War years which still remain on site. Turbine testing is still carried out on the site as part of the activities of GEC-Alsthom. Introduction the RAF as a Cranwell apprentice, followed by a three years RAF cadetship. He was an The Power Jets Factory at Whetstone may avid reader of technical books and always well have been the first factory in the world interested in engines. During his built specifically for jet engine development apprenticeship he wrote papers on jet and initial production. It was sanctioned by propulsion for aircraft, based on a the Government in 1940. Most of the conventional piston driven engine driving a original buildings are still standing, and fan to produce compressed air into which indeed the brick built cooling water pond fuel was injected and burnt to produce a jet has recently been re-commissioned as part thrust. of a large new turbine test facility. This idea had been patented long before in One has to be mindful of the fact that when 1917 and the Italians had used it in a the factory was conceived, only 34 years had practical, but unspectacular way in 1940. elapsed since the Wright Brothers flight in However, in place of the piston driven North Columbia in 1907, and neither engine Whittle favoured a fan compressor, technical or production processes had altered driving a turbine on the same shaft, the extra significantly in that period. They were power being obtained by burning fuel in the entering an era which would lead to air stream between the two. A crucial incredible increase in knowledge on the component of the design was the combustion metallurgical front, and influence world chamber. Existing compressor and turbine travel for ever. technology were only part way towards the art required since no one had ever tried to The driving force behind the Whetstone burn so much fuel per volume of combustion project was Frank Whittle, later and now Sir chamber before. Whittle recognised that the Frank Whittle, KCB, CB, FRS. He was born thermal efficiency of the gas turbine on June 1st 1907 at Earlsdon in Coventry, increases with altitude compared with a moving to Leamington in 1916 where his reduction in the efficiency of a reciprocating father ran a small engineering company. internal combustion engine. After local council primary and a Leamington secondary education, he joined 1 The Air Ministry were not impressed and Initial tests of the prototype engine, first on turned down his request for help to produce the combustion chambers and then on 12 a prototype. He persisted with his ideas, April 1937 of the complete unit were however, and took out a provisional patent undertaken at the BT-H factory at Rugby. in January 1930 based on his earlier work. In The prototype had a double-sided centrifugal the early 1930s he approached several large compressor, a single chamber combustion companies, i.e. British Thomson-Houston system and a single stage impulse expansion (BT-H), Reid and Sigrist and Armstrong turbine with an output of about 3,000hp. Siddeley to try to get them to take up his Thus, even at this early stage the prototype ideas, but to no avail. engine was giving an output power equal to the later development piston engines. The He continued his career in the RAF and by compression ratio was 4:1 double that of a July 1934 he had been selected by the Air contemporary centrifugal compressor. The Ministry to take up a two year mechanical resultant smoke, heat, dirt and general science tripos at Cambridge. In January conditions adjacent to the test site must have 1935, his original patent expired, and been quite intolerable to the other BT-H because of his personal financial situation, workers. The disruption was so great that the he could not afford the £5.00 renewal fee BT-H works engineer asked them to find and so the patent lapsed. In May 1935, another test site, and after some negotiation, however, he was put in touch with an the old BT-H foundry site, the Ladywood investment company, O.T. Falk and Works at Lutterworth, Leicestershire, was Partners. Through them and with financial offered to Power Jets Ltd for engine testing assistance from friends, together with some purposes. of his own money, a company, Power Jets Ltd, was incorporated in March 1936 with During this time, the financial state of the an authorised capital of £10,000. Following company remained very unsatisfactory, even this the Air Ministry did give tacit approval when the Air Ministry finally came up with to his work, but no financial assistance was £2,500 towards an experimental engine, forthcoming. having by then witnessed the first engine being run-up at the less than ideal test site at Whittle immediately filed three BT-H. This new experimental engine with 'improvement' patents, and the financial multiple combustion chambers was ordered position of the new company, Power Jets by Power Jets from BT-H and assembled in Limited was such that it placed an order their Rugby works and taken to Lutterworth with BT-H for the detail design and to be tested as a complete assembly, manufacture of an engine prototype, and for where it first ran in April 1938, them to allow Whittle to carry out some limited testing at their Rugby factory. Various Government departments witnessed Although still a serving officer, Whittle had the running of this multi-combustion secured an agreement with the Air Ministry chamber engine, which resulted in the Air to work on the project for no more than six Ministry agreeing to purchase it, pay for hours per week, and the Air Ministry further development, and to fund a new retained 'Free Crown User' status for the experimental aircraft with such an engine. patents. These ministry 'rights' to the BT-H agreed once more to make the engine inventions were ultimately to be of some on a cost-plus basis for Power Jets and significance. Gloster Aircraft were given the order for the 2 air frame by the Air Ministry. This engine, Eventually Power Jets, developing their known as the Whittle W 1, was completed version of the W2 engine, were told by the when the Second World War began. The WI Air Ministry that car makers Vauxhall of engine, fitted to the prototype Gloster Luton could be given the task of producing E28/39, first flew on the 15 May 1941. This six W2 engines to the Power Jets design. day is still remembered by a group of This idea was dropped after a few months engineers who worked alongside Whittle. and Power Jets were given the order for the Known as the reactionaries they hold a re- even more powerful W2 'B' engine, but they union dinner annually or so near the were not allowed to use either BT-H or anniversary date. The Germans had also Rover for its manufacture as this would been working to produce a jet-propelled delay other work they had undertaken to do aircraft and their prototype, the Heinkel for the Ministry. He178 had first flown in August 1939. By October 1940, several W2 'B' engine Whittle himself, still a serving officer was designs existed, but the only fully-fledged told by the Air Ministry to stay with Power design, with back-up, design expertise and Jets Ltd, and later in 1939 they ordered a experimental results totally integrated, was more powerful design engine the W2 from that of Power Jets. BT-H and Vauxhall both him. He tried to get the Rover Car Company admitted that the requirement to achieve the interested in the production of jet engines for Ministry's target of 2,000 units a year Power Jets, but when the Ministry heard production rate within 18 months would not about it, they discouraged Rover, saying that be easy to meet. It was suggested that Rover they, the Air Ministry, wanted to take a who already managed two 'Shadow' more active part themselves. By April 1940, factories, could possibly cope. This was the Air Ministry, who as you recall, had retained 'Free Crown Use' for the new agreed, as was the Power Jets design, and on patents and had also taken note that the 14 January 1941 Rovers were given a pre- original patent had elapsed, then approached production order for 30 engines and Glosters Rover and BT-H to produce jet engines for 12 aircraft. This was followed by further including design and development in their instructions for 20 engines per week and 30 own right, on the grounds that Power Jets more per week by making use of sub- were a development organisation and should contractors. The W2B engine also formed not worry about production. the basis of the version produced by the General Electric Company of America. This gave Rover a 'free pass' into a new industry and infuriated Whittle, since Rover However, Rover were not at all happy in were neither to share their problems or their having to accept Power Jets Design solutions with Power Jets. Whittle tried to authority. Notwithstanding these difficulties regain design control but was thwarted by the first flight on 15 May 1941 gave some the Air Ministry, who insisted that Rover moral encouragement to Frank Whittle continue.