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83-614: The Gloster E.28/39 , (also referred to as the Gloster Whittle , Gloster Pioneer , or Gloster G.40 ) was the first British turbojet-engined aircraft first flying in 1941. It was the third turbojet aircraft to fly after the German Heinkel He 178 (1939) and Heinkel He 280 (1941), the Italian Caproni Campini N.1 of 1940 being a motor jet and not a true turbojet. The E.28/39 was the product of

166-416: A i r + m ˙ f ) V j − m ˙ a i r V {\displaystyle F_{N}=({\dot {m}}_{air}+{\dot {m}}_{f})V_{j}-{\dot {m}}_{air}V} where: If the speed of the jet is equal to sonic velocity the nozzle is said to be " choked ". If the nozzle is choked, the pressure at the nozzle exit plane

249-487: A Napier Sabre piston engine which attracted the attention of Whittle who thought that the layout would be suitable for his new engine. Although the design Whittle saw would not progress beyond the project stage, within a few weeks, Carter was asked by the Air Ministry to submit plans for a brand new aircraft to use Whittle's engine. He agreed to the project before seeing the engine for himself. While not impressed with

332-555: A Power Jets W.2 engine – joined the test programme on 1 March 1943. Flying of W4046 was by Gloster test pilots John Grierson and John Crosby Warren, because Michael Daunt was then involved with the F.9/40 (which would enter service as the Gloster Meteor ). Testing revealed problems with engine oil and lubricants. In April 1943, W4046 flew to Hatfield for a demonstration in front of the Prime Minister and members of

415-441: A specification which had been issued by the Air Ministry for a suitable aircraft to test the novel jet propulsion designs that Frank Whittle had been developing during the 1930s. Gloster and the company's chief designer, George Carter , worked with Whittle to develop an otherwise conventional aircraft fitted with a Power Jets W.1 turbojet engine. Flying for the first time on 15 May 1941, two E.28/39 aircraft were produced for

498-585: A gas turbine to power an aircraft was filed in 1921 by Frenchman Maxime Guillaume . His engine was to be an axial-flow turbojet, but was never constructed, as it would have required considerable advances over the state of the art in compressors. In 1928, British RAF College Cranwell cadet Frank Whittle formally submitted his ideas for a turbojet to his superiors. In October 1929 he developed his ideas further. On 16 January 1930 in England, Whittle submitted his first patent (granted in 1932). The patent showed

581-554: A high-altitude jet-powered bomber; following the start of the Second World War and the Battle for France , a greater national emphasis on fighter aircraft arose. Power Jets and Gloster quickly formed a mutual understanding around mid-1939. In September 1939, the Air Ministry issued a specification to Gloster for an aircraft to test one of Frank Whittle 's turbojet designs in flight. The E.28/39 designation originates from

664-542: A landing field, lengthening flights. The increase in reliability that came with the turbojet enabled three- and two-engine designs, and more direct long-distance flights. High-temperature alloys were a reverse salient , a key technology that dragged progress on jet engines. Non-UK jet engines built in the 1930s and 1940s had to be overhauled every 10 or 20 hours due to creep failure and other types of damage to blades. British engines, however, utilised Nimonic alloys which allowed extended use without overhaul, engines such as

747-423: A maximum true speed of 350 mph (560 km/h) was attained, in level flight at 25,000 ft (7,600 m) and 17,000 turbine revolutions per minute. Tests continued with increasingly refined versions of the engine. Small, auxiliary fins were added near the tips of the tailplanes to provide additional stability in high-speed flight. John Grierson, in 1971, called these "end-plates" and wrote that their purpose

830-492: A non-flightworthy version of the Power Jets W.1 engine. Frank Whittle, who had been an RAF flying instructor and test pilot before specializing in engineering, did taxi runs on the grass airfield up to 60 mph (97 km/h) and Gloster's Chief Test Pilot, Flight Lieutenant Gerry Sayer did further taxi tests before becoming airborne for 200 to 300 yd (180 to 270 m), which he repeated two more times. Following

913-405: A normal fuselage with long jet-pipe and exhaust nozzle behind the tail, and a short fuselage and jet-pipe with the tail-plane supported on an extension boom. Flanagan highlights the advantage of a short jet-pipe as incurring a lower thrust loss. Buttler reports Gloster engineer Richard Walker considered a short fuselage would overcome structural, accessibility and maintenance difficulties and increase

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996-459: A second generation SST engine using the 593 core were done more than three years before Concorde entered service. They evaluated bypass engines with bypass ratios between 0.1 and 1.0 to give improved take-off and cruising performance. Nevertheless, the 593 met all the requirements of the Concorde programme. Estimates made in 1964 for the Concorde design at Mach 2.2 showed the penalty in range for

1079-411: A significant impact on commercial aviation . Aside from giving faster flight speeds turbojets had greater reliability than piston engines, with some models demonstrating dispatch reliability rating in excess of 99.9%. Pre-jet commercial aircraft were designed with as many as four engines in part because of concerns over in-flight failures. Overseas flight paths were plotted to keep planes within an hour of

1162-405: A small helicopter engine compressor rotates around 50,000 RPM. Turbojets supply bleed air from the compressor to the aircraft for the operation of various sub-systems. Examples include the environmental control system , anti-icing , and fuel tank pressurization. The engine itself needs air at various pressures and flow rates to keep it running. This air comes from the compressor, and without it,

1245-426: A small low-wing aircraft of conventional configuration. The jet intake was located in the nose, while the single tail-fin and elevators were mounted above the jet-pipe, although due to uncertainty about the spinning characteristics of a jet aircraft, at an earlier design stage an alternative arrangement using twin fins and rudders was considered. Two jet pipe/rear fuselage arrangements were also originally considered,

1328-513: A turbojet application, where the output from the gas turbine is used in a propelling nozzle, raising the turbine temperature increases the jet velocity. At normal subsonic speeds this reduces the propulsive efficiency, giving an overall loss, as reflected by the higher fuel consumption, or SFC. However, for supersonic aircraft this can be beneficial, and is part of the reason why the Concorde employed turbojets. Turbojet systems are complex systems therefore to secure optimal function of such system, there

1411-512: A turbojet engine is always subsonic, regardless of the speed of the aircraft itself. The intake has to supply air to the engine with an acceptably small variation in pressure (known as distortion) and having lost as little energy as possible on the way (known as pressure recovery). The ram pressure rise in the intake is the inlet's contribution to the propulsion system's overall pressure ratio and thermal efficiency . The intake gains prominence at high speeds when it generates more compression than

1494-494: A turbojet is high enough at higher thrust settings to cause the nozzle to choke. If, however, a convergent-divergent de Laval nozzle is fitted, the divergent (increasing flow area) section allows the gases to reach supersonic velocity within the divergent section. Additional thrust is generated by the higher resulting exhaust velocity. Thrust was most commonly increased in turbojets with water/methanol injection or afterburning . Some engines used both methods. Liquid injection

1577-487: A two-stage axial compressor feeding a single-sided centrifugal compressor . Practical axial compressors were made possible by ideas from A.A. Griffith in a seminal paper in 1926 ("An Aerodynamic Theory of Turbine Design"). Whittle later concentrated on the simpler centrifugal compressor only, for a variety of practical reasons. A Whittle engine was the first turbojet to run, the Power Jets WU , on 12 April 1937. It

1660-553: A visit to the premises of the Gloster Aircraft Company, where he met several key figures, such as George Carter , Gloster's chief designer. Carter took a keen interest in Whittle's project, particularly when he saw the operational Power Jets W.1 engine; Carter quickly made several rough proposals of various aircraft designs powered by the engine. Independently, Whittle had also been producing several proposals for

1743-415: Is a call for the newer models being developed to advance its control systems to implement the newest knowledge from the areas of automation, so increase its safety and effectiveness. George Carter (engineer) Wilfred George Carter CBE FRAeS (9 March 1889 – 27 February 1969) was a British engineer, who was the chief designer at Glosters from 1937. He was awarded the C.B.E. in 1947 and

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1826-413: Is a component of a turbojet used to divert air into the intake, in front of the accessory drive and to house the starter motor. An intake, or tube, is needed in front of the compressor to help direct the incoming air smoothly into the rotating compressor blades. Older engines had stationary vanes in front of the moving blades. These vanes also helped to direct the air onto the blades. The air flowing into

1909-590: Is a most pleasant little aeroplane to handle, particularly on account of the excellent field of vision from the pilot's seat ...." Although the initial flight tests were relatively early in the Second World War, the German Heinkel He 178 had been first test-flown on 27 August 1939, at Rostock-Marienehe on the Baltic Coast , days before the outbreak of the war. The E.28/39 was delivered to Brockworth for ground tests beginning on 7 April 1941, using

1992-523: Is greater than atmospheric pressure, and extra terms must be added to the above equation to account for the pressure thrust. The rate of flow of fuel entering the engine is very small compared with the rate of flow of air. If the contribution of fuel to the nozzle gross thrust is ignored, the net thrust is: F N = m ˙ a i r ( V j − V ) {\displaystyle F_{N}={\dot {m}}_{air}(V_{j}-V)} The speed of

2075-573: Is modelled approximately by the Brayton cycle . The efficiency of a gas turbine is increased by raising the overall pressure ratio, requiring higher-temperature compressor materials, and raising the turbine entry temperature, requiring better turbine materials and/or improved vane/blade cooling. It is also increased by reducing the losses as the flow progresses from the intake to the propelling nozzle. These losses are quantified by compressor and turbine efficiencies and ducting pressure losses. When used in

2158-589: Is more commonly by use of a turboshaft engine, a development of the gas turbine engine where an additional turbine is used to drive a rotating output shaft. These are common in helicopters and hovercraft. Turbojets were widely used for early supersonic fighters , up to and including many third generation fighters , with the MiG-25 being the latest turbojet-powered fighter developed. As most fighters spend little time traveling supersonically, fourth-generation fighters (as well as some late third-generation fighters like

2241-778: Is on display in the middle of a roundabout at Lutterworth in Leicestershire , where the aircraft's engine was produced. A full-scale model taken from the same moulds, with authentic paint scheme and detailing, has been built by members of the Jet Age Museum in Gloucestershire. It has been on display in Brockworth, Gloucester, Kemble (at both the Kemble Air Day and the MVT Show), and formed part of

2324-603: The Air Staff . It was taken to Farnborough and fitted with a 1,500 lbf (6.7 kN) W2.B and achieved 466 mph. On 30 July 1943, while on a high-altitude test flight, the second prototype was destroyed in a crash resulting from an aileron failure. The accident was attributed to the use of the wrong type of grease in the aileron controls; one aileron was "stuck in position, sending the aircraft out of control". The test pilot, Squadron Leader Douglas Davie, bailed out from 33,000 ft (10,000 m), suffering frostbite on

2407-656: The De Havilland DH.72 bomber (only one was ever built), which was given to Gloster from de Havilland. At Gloster Aircraft, Carter was instrumental in the design of two of the most significant biplane fighters for the RAF, the Gauntlet and Gladiator . Carter also designed the Gloster F.9/37 a promising twin-engine ( Bristol Taurus ) fighter design that never entered production, before he turned to work on jet aircraft. He

2490-621: The F-111 and Hawker Siddeley Harrier ) and subsequent designs are powered by the more efficient low-bypass turbofans and use afterburners to raise exhaust speed for bursts of supersonic travel. Turbojets were used on Concorde and the longer-range versions of the Tu-144 which were required to spend a long period travelling supersonically. Turbojets are still common in medium range cruise missiles , due to their high exhaust speed, small frontal area, and relative simplicity. The first patent for using

2573-641: The Gloster Meteor , entered service in 1944, towards the end of World War II , the Me 262 in April and the Gloster Meteor in July. Only about 15 Meteor saw WW2 action but up to 1400 Me 262s were produced, with 300 entering combat, delivering the first ground attacks and air combat victories of jet planes. Air is drawn into the rotating compressor via the intake and is compressed to a higher pressure before entering

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2656-588: The Heinkel HeS 3 ), or an axial compressor (as in the Junkers Jumo 004 ) which gave a smaller diameter, although longer, engine. By replacing the propeller used on piston engines with a high speed jet of exhaust, higher aircraft speeds were attainable. One of the last applications for a turbojet engine was Concorde which used the Olympus 593 engine. However, joint studies by Rolls-Royce and Snecma for

2739-590: The Heron and Hornbill fighter aircraft, and the Horsley bomber. From 1924 to 1928 he worked with Short Bros of Rochester , designing a seaplane for the 1927 Schneider Trophy. From 1928 to 1931, Carter worked for de Havilland . From 1935 to 1936, he also worked for Avro . Carter joined the Gloucestershire (later Gloster) Aircraft Company , at Brockworth, Gloucestershire , in 1931. He initially worked on

2822-527: The North American XB-70 Valkyrie , each feeding three engines with an intake airflow of about 800 pounds per second (360 kg/s). The turbine rotates the compressor at high speed, adding energy to the airflow while squeezing (compressing) it into a smaller space. Compressing the air increases its pressure and temperature. The smaller the compressor, the faster it turns. The (large) GE90-115B fan rotates at about 2,500 RPM, while

2905-488: The Rolls-Royce Welland and Rolls-Royce Derwent , and by 1949 the de Havilland Goblin , being type tested for 500 hours without maintenance. It was not until the 1950s that superalloy technology allowed other countries to produce economically practical engines. Early German turbojets had severe limitations on the amount of running they could do due to the lack of suitable high temperature materials for

2988-424: The Tu-144 , also used afterburners as does Scaled Composites White Knight , a carrier aircraft for the experimental SpaceShipOne suborbital spacecraft. Reheat was flight-trialled in 1944 on the W.2/700 engines in a Gloster Meteor I . The net thrust F N {\displaystyle F_{N}\;} of a turbojet is given by: F N = ( m ˙

3071-580: The prototype . The contract to build the E.28/39 also known as the Pioneer was placed with Gloster on 3 February 1940. The aircraft was built in secret at the Regents garage, Cheltenham and first flew on 15 April 1941 at RAF Cranwell , becoming the first British and Allied jet aircraft. Even before the Pioneer flew, the Air Ministry encouraged Carter to design a practical jet fighter since the Pioneer

3154-510: The Air." Other partnerships featured on the stamps were R. J. Mitchell and Supermarine's celebrated Spitfire on the 20p stamp, R.E. Bishop and the de Havilland company's Mosquito on a 37p stamp and Sydney Camm , designer of the Hawker Hunter fighter, featured on the 63p value. Chairman of Royal Mail 's Stamp Advisory Committee, Adam Novak said: "Each one of the aircraft featured on

3237-544: The Gloster GA-5 delta-wing fighter (later the Gloster Javelin which first flew in 1951 from RAF Moreton Valence south of Gloucester), which was designed by Richard Walker (Gloster's chief designer) and powered by Armstrong Siddeley Sapphire engines. Along with other pioneering aircraft designers, Carter was honoured in 1997 with the issuance of a special postage stamp in a series called "The Architects of

3320-464: The aircraft decreases the efficiency of the engine because it has been compressed, but then does not contribute to producing thrust. Compressor types used in turbojets were typically axial or centrifugal. Early turbojet compressors had low pressure ratios up to about 5:1. Aerodynamic improvements including splitting the compressor into two separately rotating parts, incorporating variable blade angles for entry guide vanes and stators, and bleeding air from

3403-446: The aircraft having been developed in conformance with the 28th "Experimental" specification issued by the Air Ministry in 1939. The E.28/39 specification required the aircraft to carry two 0.303 in (7.62 mm) Browning machine guns in each wing, along with 2,000 rounds of ammunition, but these were never fitted. The second paragraph of the contract for the first aeroplane stated: "The primary object of this aeroplane will be to flight test

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3486-410: The combustion chamber. Fuel is mixed with the compressed air and burns in the combustor. The combustion products leave the combustor and expand through the turbine where power is extracted to drive the compressor. The turbine exit gases still contain considerable energy that is converted in the propelling nozzle to a high speed jet. The first turbojets, used either a centrifugal compressor (as in

3569-432: The combustor and pass through to the turbine in a continuous flowing process with no pressure build-up. Instead, a small pressure loss occurs in the combustor. The fuel-air mixture can only burn in slow-moving air, so an area of reverse flow is maintained by the fuel nozzles for the approximately stoichiometric burning in the primary zone. Further compressed air is introduced which completes the combustion process and reduces

3652-483: The completion of these ground tests, the aircraft was fitted with a flightworthy engine rated for 10 hours use, and then partially dismantled and transported to RAF Cranwell , near Sleaford in Lincolnshire which had a long runway and no high ground in the vicinity. On 15 May 1941, Gerry Sayer flew the aircraft under jet power for the first time, in a flight lasting 17 minutes. In this first series of test flights,

3735-421: The compressor enabled later turbojets to have overall pressure ratios of 15:1 or more. After leaving the compressor, the air enters the combustion chamber. The burning process in the combustor is significantly different from that in a piston engine . In a piston engine, the burning gases are confined to a small volume, and as the fuel burns, the pressure increases. In a turbojet, the air and fuel mixture burn in

3818-401: The compressor is passed through these to keep the metal temperature within limits. The remaining stages do not need cooling. In the first stage, the turbine is largely an impulse turbine (similar to a pelton wheel ) and rotates because of the impact of the hot gas stream. Later stages are convergent ducts that accelerate the gas. Energy is transferred into the shaft through momentum exchange in

3901-536: The compressor stage. Well-known examples are the Concorde and Lockheed SR-71 Blackbird propulsion systems where the intake and engine contributions to the total compression were 63%/8% at Mach 2 and 54%/17% at Mach 3+. Intakes have ranged from "zero-length" on the Pratt & Whitney TF33 turbofan installation in the Lockheed C-141 Starlifter , to the twin 65 feet (20 m) long, intakes on

3984-578: The development of the Gloster Meteor , the first operational jet fighter to enter service with the Allies . The first prototype continued test flying until 1944, after which it was withdrawn from service; in 1946, it was transferred to the Science Museum in London , where it has been on static display ever since; full-scale replicas have been created. The development of the turbojet -powered E.28/39

4067-672: The display for the Sir Frank Whittle Centenary commemorations at RAF Cranwell in June 2007. Data from Gloster Aircraft since 1917 General characteristics Performance Armament Related lists Turbojet Turbojets have poor efficiency at low vehicle speeds, which limits their usefulness in vehicles other than aircraft. Turbojet engines have been used in isolated cases to power vehicles other than aircraft, typically for attempts on land speed records . Where vehicles are "turbine-powered", this

4150-499: The engine installation, but the design shall be based on requirements for a fixed gun interceptor fighter as far as the limitations of size and weight imposed by the power unit permit. The armament equipment called for in this specification will not be required for initial trials but the contractor will be required to make provision in the design for the weight and space occupied by these items..." Early on, Gloster's chief designer, George Carter , worked closely with Whittle, and laid out

4233-447: The engine itself, when he saw it running he was convinced that it could develop into a suitable powerplant given what they had managed to achieve in the somewhat primitive conditions at Lutterworth . The Gloster E.28/39 was designed primarily to prove the concept of turbojet powered flight, the Air Ministry however insisted that the design include provision for four guns and 2,000 rounds of ammunition even if these were not fitted in

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4316-434: The era. It had a retractable undercarriage which was actuated by a hydraulic accumulator, with a manually-operated hand-pump to serve as a backup. Emergency actuation used compressed air. The flaps were also hydraulically actuated, using the hand-pump. Unusually, the nose wheel was steerable, using the rudder control, which aided in ground manoeuvring. The E.28/39 was powered by a Power Jets W.1 turbojet engine behind

4399-404: The first production jet-propelled aircraft to enter service with the Allies . The E.28/39 was a low-wing monoplane designed around the new jet engine. It was described as possessing a slightly tubby appearance as a result of a round fuselage. Due to the elimination of any risk that would have been posed by propeller tips striking the ground, the E.28/39 had an unusually short undercarriage for

4482-426: The flight test programme. Following initial satisfactory reports, these aircraft continued to be flown to test increasingly refined engine designs and new aerodynamic features. Despite the loss of the second prototype, due to improper maintenance causing a critical aileron failure, the E.28/39 was considered to be a success. The E.28/39 contributed valuable initial experience with the new type of propulsion and led to

4565-430: The fuel system had simply one low-pressure valve between the tank and the engine pump, and one high-pressure valve between the pump and the engine. There was no electric booster pump. Secondly the absence of vibration or the sensation of effort being transmitted to the pilot's seat was outstanding." and "The very favourable impressions of jet propulsion obtained ... have all been endorsed by subsequent flights ... The E.28

4648-475: The high-temperature materials used in their turbosuperchargers during World War II. Water injection was a common method used to increase thrust, usually during takeoff, in early turbojets that were thrust-limited by their allowable turbine entry temperature. The water increased thrust at the temperature limit, but prevented complete combustion, often leaving a very visible smoke trail. Allowable turbine entry temperatures have increased steadily over time both with

4731-441: The introduction of superior alloys and coatings, and with the introduction and progressive effectiveness of blade cooling designs. On early engines, the turbine temperature limit had to be monitored, and avoided, by the pilot, typically during starting and at maximum thrust settings. Automatic temperature limiting was introduced to reduce pilot workload and reduce the likelihood of turbine damage due to over-temperature. A nose bullet

4814-401: The jet V j {\displaystyle V_{j}\;} must exceed the true airspeed of the aircraft V {\displaystyle V\;} if there is to be a net forward thrust on the airframe. The speed V j {\displaystyle V_{j}\;} can be calculated thermodynamically based on adiabatic expansion . The operation of a turbojet

4897-488: The lack of a generator and limited battery capacity, the latter being devoted to the automated sensors and recording devices that captured the results of each flight, meant this was not possible; pilots had to endure the cold cockpit. John Grierson said: "The main impressions of my first jet-propelled flight were first of the simplicity of operation. The throttle was the only engine control; there were no mixture or propeller levers, supercharger or cooling-gill controls and

4980-503: The limits of engineering capability. Securing funding was a persistently worrying issue throughout the early development of the engine. The first Whittle prototype jet engine, the Power Jets WU , began running trials in early 1937; shortly afterwards, both Sir Henry Tizard , chairman of the Aeronautical Research Committee , and the Air Ministry gave the project their support. On 28 April 1939, Whittle made

5063-462: The maximum speed of the aircraft. Due to the unknown effects of the jet efflux on the boom-mounted tailplane, the long fuselage was selected. On 3 February 1940, a contract for two prototypes was signed by the Air Ministry. Manufacture of the E.28/39 commenced at Brockworth near Gloucester and then moved to Regent Motors in Regent Street, Cheltenham (now the site of Regent Arcade), which

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5146-451: The operational philosophy was that, once the prototypes had proved the capabilities of the design, a more substantial programme would begin: even before the first flight of the E.28/39, this aircraft had been envisaged as being a considerably more elaborate twin-engined design, with all of the equipment required in a fighter aircraft. This aircraft, also produced by Gloster, became the Meteor ,

5229-402: The opposite way to energy transfer in the compressor. The power developed by the turbine drives the compressor and accessories, like fuel, oil, and hydraulic pumps that are driven by the accessory gearbox. After the turbine, the gases expand through the exhaust nozzle producing a high velocity jet. In a convergent nozzle, the ducting narrows progressively to a throat. The nozzle pressure ratio on

5312-410: The pilot and the fuel tank. The engine exhaust was directed through the centre of the fuselage, the jetpipe terminating about two feet behind the rudder . A nose air-intake led the air through bifurcated ducts around the cockpit. A fuel tank, containing up to 82 Imp gal (372.8 litres), was behind the cockpit, supposed to have been adopted as a countermeasure against the impact of negative g , which posed

5395-599: The risk of causing the engine to flame out, which was hard to re-light during flight. The E.28/39 lacked features that would be expected for a fighter, such as a radio . The original engine was started using an Austin Seven car engine, connected by a flexible drive; it was replaced on the flight engine with an electric starter that used a ground-cart battery. The cockpit, which had a sliding canopy, had no pressurisation or any form of climate control, such as heating. Pilots were intended to wear electrically-heated flight suits but

5478-416: The stamps was unique and revolutionary in its own way. The Architects of the Air were the trail blazers for today's modern aircraft designs. " George Carter's face dramatically forms the clouds overlooking a flight of a Meteor Mk T7 on the 1997 43p stamp. In March 2022, Gloucester City Homes dedicated to Carter a newly built residential building near the old Gloster aircraft factory. (Wilfred) George Carter

5561-468: The supersonic airliner, in terms of miles per gallon, compared to subsonic airliners at Mach 0.85 (Boeing 707, DC-8) was relatively small. This is because the large increase in drag is largely compensated by an increase in powerplant efficiency (the engine efficiency is increased by the ram pressure rise which adds to the compressor pressure rise, the higher aircraft speed approaches the exhaust jet speed increasing propulsive efficiency). Turbojet engines had

5644-446: The temperature of the combustion products to a level which the turbine can accept. Less than 25% of the air is typically used for combustion, as an overall lean mixture is required to keep within the turbine temperature limits. Hot gases leaving the combustor expand through the turbine. Typical materials for turbines include inconel and Nimonic . The hottest turbine vanes and blades in an engine have internal cooling passages. Air from

5727-493: The thrust from a turbojet engine. It was flown by test pilot Erich Warsitz . The Gloster E.28/39 , (also referred to as the "Gloster Whittle", "Gloster Pioneer", or "Gloster G.40") made the first British jet-engined flight in 1941. It was designed to test the Whittle jet engine in flight, and led to the development of the Gloster Meteor. The first two operational turbojet aircraft, the Messerschmitt Me 262 and then

5810-412: The turbines would overheat, the lubricating oil would leak from the bearing cavities, the rotor thrust bearings would skid or be overloaded, and ice would form on the nose cone. The air from the compressor, called secondary air, is used for turbine cooling, bearing cavity sealing, anti-icing, and ensuring that the rotor axial load on its thrust bearing will not wear it out prematurely. Supplying bleed air to

5893-471: The turbines. British engines such as the Rolls-Royce Welland used better materials giving improved durability. The Welland was type-certified for 80 hours initially, later extended to 150 hours between overhauls, as a result of an extended 500-hour run being achieved in tests. General Electric in the United States was in a good position to enter the jet engine business due to its experience with

5976-442: The way down. The first prototype was fitted with the 1,700 lbf (7.6 kN) thrust W2/500 and was flown to 42,000 ft (13,000 m), but level speed at altitude was not attempted, due to fuel shortage. The pilot commented in his report on a need for cockpit heating and a larger fuel tank. The aircraft continued flight tests until 1944. By that time, more advanced turbojet-powered aircraft were available. The Gloster E.28/39

6059-490: Was Chief Designer from 1936 to 1948. In 1934 Gloster had been taken over by Hawker, causing the chief designer, Henry Folland , to leave, making way for his successor. It was during a visit by Frank Whittle to Gloster that Carter became involved in the development of jet aircraft . At the time Gloster were working on a twin-boom fighter, for specification F.18/37 - also used for the Hawker Typhoon , to be powered by

6142-514: Was appointed Technical Director of Gloster Aircraft in 1948 remaining on the board of directors until 1954. He continued to serve Glosters for a number of years after his retirement in a consultancy role until 1958. He designed the first British jet aircraft. Carter had his apprenticeship with W. H. Allen Sons and Co. Ltd of Bedford from 1906 to 1912. From 1916 to 1920 he was Chief Draughtsman of Sopwith Aviation Company , then Chief Designer from 1920 to 1924 of Hawker Engineering Co. Ltd , working on

6225-471: Was considered safer from bombing. Whittle was dissatisfied with the slowness of production, probably caused by the Battle of Britain as the area around nearby Coventry was subject to high levels of German bomber activity. In April 1941, the first of the E.28/39 prototypes was completed but a flight-worthy W.1A engine was not available and a ground-use only W.1X unit was assembled and installed for taxiing tests only. While only two prototypes had been ordered,

6308-416: Was later able to achieve high speeds, the highest being 505 mph (813 km/h) at 30,000 ft (9,100 m) with a W.2/700 engine and it proved to be a useful experimental aircraft with a "good climb rate and ceiling". Experience with the E.28/39 paved the way for Britain's first operational jet fighter aircraft , the Gloster Meteor . The Meteor was powered by two Rolls-Royce Welland engines, which

6391-424: Was liquid-fuelled. Whittle's team experienced near-panic during the first start attempts when the engine accelerated out of control to a relatively high speed despite the fuel supply being cut off. It was subsequently found that fuel had leaked into the combustion chamber during pre-start motoring checks and accumulated in pools, so the engine would not stop accelerating until all the leaked fuel had burned off. Whittle

6474-404: Was not suitable because it was unlikely that an engine of at least 2,000 lbf (8.9 kN) thrust would be available in the near future. Carter therefore decided that the design would require two engines. The result was designated the F.9/40 which first flew on 5 March 1943 and would find worldwide fame as the Gloster Meteor . His later designs included the E.1/44 . He supervised the design of

6557-586: Was tested on the Power Jets W.1 in 1941 initially using ammonia before changing to water and then water-methanol. A system to trial the technique in the Gloster E.28/39 was devised but never fitted. An afterburner or "reheat jetpipe" is a combustion chamber added to reheat the turbine exhaust gases. The fuel consumption is very high, typically four times that of the main engine. Afterburners are used almost exclusively on supersonic aircraft , most being military aircraft. Two supersonic airliners, Concorde and

6640-586: Was the next stage in development from the Power Jets W.1. In 1946, the first prototype ( W4041 ) was placed in the Science Museum in Central London, where it is exhibited today in the Flight Gallery. A full-size replica has been placed on an obelisk on a roundabout near the northern perimeter of Farnborough Airfield in Hampshire , as a memorial to Sir Frank Whittle. A similar full-size model

6723-637: Was the product of a collaboration between the Gloster Aircraft Company and Sir Frank Whittle 's firm, Power Jets Ltd. Whittle formed Power Jets Ltd in March 1936 to develop his ideas of jet propulsion, Whittle himself serving as the company's chief engineer. For several years, attracting financial backers and aviation firms prepared to take on Whittle's radical ideas was difficult; in 1931, Armstrong-Siddeley had evaluated and rejected Whittle's proposal, finding it to be technically sound but at

6806-520: Was to increase the fin area due to the problem of rudder blanking in a side-slip. On 21 October 1942, Sayer disappeared during a flight in a Hawker Typhoon , presumed killed in a collision and his assistant, Michael Daunt , took over testing of the E.28/39. The oil system had been changed before he flew: after it was proven, the aircraft then being handed over to the RAE for testing by service pilots. The second prototype E.28/39 ( W4046 ) – initially powered by

6889-485: Was unable to interest the government in his invention, and development continued at a slow pace. In Germany, Hans von Ohain patented a similar engine in 1935. His design, an axial-flow engine, as opposed to Whittle's centrifugal flow engine, was eventually adopted by most manufacturers by the 1950s. On 27 August 1939 the Heinkel He 178 , powered by von Ohain's design, became the world's first aircraft to fly using

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