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In 1930, Frank Whittle took out a patent on the turbojet engine — nine years before the war. By 1937, he had built a prototype, without Air Ministry support.

Finally, in 1944, the RAF received seven Gloster Meteors — which saw some action in the war:

The Meteor was initially used to counter the V-1 flying bomb threat. 616 Squadron Meteors saw action for the first time on 27 July 1944, when three aircraft were active over Kent. These were the first operational jet combat missions for the Meteor and for the Royal Air Force. After some problems, especially with jamming guns, the first two V1 “kills” were made on 4 August. By war’s end, Meteors accounted for 14 flying bombs. After the end of the V-1 threat, and the introduction of the ballistic V-2 rocket, the RAF was forbidden to fly the Meteor on combat missions over German-held territory for fear of an aircraft being shot down and salvaged by the Germans.

No. 616 Squadron briefly moved to RAF Debden to allow USAAF bomber crews to gain experience and create tactics in facing jet-engined foes before moving to Colerne, Wiltshire. For a week from 10 October 1944 a series of exercises were carried out in which a flight of Meteors made mock attacks on a formation of 100 B-24s and B-17s escorted by 40 Mustangs and Thunderbolts. These suggested if the jet fighter attacked the formation from above it could take advantage of its superior speed in the dive to attack the bombers and then escape by diving through the formation before the escorts could react. The best tactic to counter this was to place a fighter screen 5,000 ft above the bombers and attempt to intercept the jets early in the dive.

Whittle’s story is interesting. He grew up working in his father’s machine shop and reading in the library. At 15, he joined the RAF — or tried:

In January 1923, having passed the RAF entrance examination with flying colours Whittle reported to RAF Halton as an aircraft apprentice. He lasted only two days: just five feet tall and with a small chest measurement, he failed the medical.[3] He then put himself through a vigorous training programme and special diet devised by a physical training instructor at Halton to build up his physique, only to fail again six months later, when he was told that he could not be given a second chance, despite having added three inches to his height and chest.[7] Undeterred, he applied again under an assumed name and presented himself as a candidate at the RAF Cranwell apprentice school instead. This time he passed the physical, and in September that year, 364365 Boy Whittle, F started his three-year training as an aircraft mechanic at the No. 4 Apprentices Wing, No. 1 School of Technical Training.[8]

Whittle hated the strict discipline and, convinced there was no hope of ever becoming a pilot, at one time seriously considered deserting.[8] However, throughout his early days as an aircraft apprentice, first at the Royal Air Force College Cranwell, and later at RAF Halton, he maintained his interest in the Model Aircraft Society, where he built replicas. The quality of these attracted the eye of his commanding officer, who felt that Whittle was also a mathematical genius. He was so impressed that in 1926 he recommended Whittle for officer training at Cranwell.[3]

For Whittle, this was the chance of a lifetime, not only to enter the commissioned ranks but also because the training included flying lessons on the Avro 504.[3] While at Cranwell he lodged in a bungalow at Dorrington. Being an ex-apprentice amongst a majority of ex-public schoolboys, life as an officer cadet was not easy for him, but he nevertheless excelled in the courses and went solo in 1927 after only 13.5 hours instruction, quickly progressing to the Bristol Fighter and gaining a reputation for daredevil low flying and aerobatics.[8]

A requirement of the course was that each student had to produce a thesis for graduation: Whittle decided to write his on potential aircraft design developments, notably flight at high altitudes and speeds over 500 mph (800 km/h). In Future Developments in Aircraft Design he showed that incremental improvements in existing propeller engines were unlikely to make such flight routine. Instead he described what is today referred to as a motorjet; a motor using a conventional piston engine to provide compressed air to a combustion chamber whose exhaust was used directly for thrust – essentially an afterburner attached to a propeller engine. The idea was not new and had been talked about for some time in the industry, but Whittle’s aim was to demonstrate that at increased altitudes the lower outside air pressure would increase the design’s efficiency. For long-range flight, using an Atlantic-crossing mailplane as his example, the engine would spend most of its time at high altitude and thus could outperform a conventional powerplant.[3]

Of the few apprentices accepted, only about one percent normally completed the course, and Whittle graduated in 1928 at the age of 21, being commissioned as a Pilot Officer in July.[9] He ranked second in his class in academics, won the Andy Fellowes Memorial Prize for Aeronautical Sciences for his thesis, and was described as an “exceptional to above average” pilot.[3] However, his flight logbook also showed numerous red ink warnings about showboating and overconfidence,[3] and because of dangerous flying in an Armstrong Whitworth Siskin he was disqualified from the end of term flying contest.[8]

Whittle continued working on the motorjet principle after his thesis work but eventually abandoned it when further calculations showed it would weigh as much as a conventional engine of the same thrust. Pondering the problem he thought: “Why not substitute a turbine for the piston engine?” Instead of using a piston engine to provide the compressed air for the burner, a turbine could be used to extract some power from the exhaust and drive a similar compressor to those used for superchargers. The remaining exhaust thrust would power the aircraft.[10]

On 27 August 1928 Pilot Officer Whittle joined No. 111 Squadron, Hornchurch, flying Siskin IIIs. His continuing reputation for low flying and aerobatics provoked a public complaint that almost led to his being court-martialled.[11] Within a year he was posted to Central Flying School, Wittering, for a flying instructor’s course. He became a popular and gifted instructor, and was selected as one of the entrants in a competition to select a team to perform the “crazy flying” routine in the 1930 Royal Air Force Air Display at RAF Hendon. He destroyed two aircraft in accidents during rehearsals but remained unscathed on both occasions. After the second incident an enraged Flight Lieutenant Harold W. Raeburn said furiously, “Why don’t you take all my bloody aeroplanes, make a heap of them in the middle of the aerodrome and set fire to them – it’s quicker!”[11]

Whittle showed his engine concept around the base, where it attracted the attention of Flying Officer Pat Johnson, formerly a patent examiner. Johnson, in turn, took the concept to the commanding officer of the base. This set in motion a chain of events that almost led to the engines being produced much sooner than actually occurred.[3]

Earlier, in July 1926, A. A. Griffith had published a paper on compressors and turbines, which he had been studying at the Royal Aircraft Establishment (RAE). He showed that such designs up to this point had been flying “stalled”, and that by giving the compressor blades an aerofoil-shaped cross-section 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.

Encouraged by his Commanding Officer, in late 1929 Whittle sent his concept to the Air Ministry to see if it would be of any interest to them. 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. Griffith appears to have been convinced that Whittle’s “simple” design could never achieve the sort of efficiencies needed for a practical engine. After pointing out an error in one of Whittle’s 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 inefficient. The RAF returned his comment to Whittle, referring to the design as being “impracticable”.[3]

Pat Johnson remained convinced of the validity of the idea, and had Whittle patent the idea in January 1930. Since the RAF was not interested in the concept they did not declare it secret, meaning that Whittle was able to retain the rights to the idea, which would have otherwise been their property. Johnson arranged a meeting with British Thomson-Houston (BTH), whose chief turbine engineer seemed to agree with the basic idea. However, BTH did not want to spend the ?60,000 it would cost to develop it, and this potential brush with early success went no further.[3]

The Battle of Britain could have looked very, very different.

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