The Bristol Orion aero engine was a two-shaft turboprop intended for use in later marks of the Bristol Britannia and Canadair CL-44. Although the engine was built and underwent a development program, the BE.25 Orion project was cancelled in 1958 by the British Ministry of Supply. At that time, interest in turboprop powered aircraft was beginning to wane, because of the successful introduction of the Boeing 707 and Douglas DC-8 jetliners into airline service.
A single stage HP turbine drove a five stage all-axial HP compressor, whilst a three stage LP turbine drove both the seven stage LP compressor and the propeller, via a reduction gearbox. Thus the Orion used a shared load LP turbine (like the Rolls-Royce Tyne), whereas its predecessor, the Bristol Proteus, had a free-power turbine. The combustor used separate flame cans.
One novel feature of the Orion was a derate from a thermodynamic rating of 9,000 shp at sea level, to enable a constant 5,150 ehp power level to be maintained all the way up to 15,000 ft altitude. The Orion project was cancelled in January 1958, at a reported total cost of £ 4.75 million.
Applications: Bristol Britannia
Specifications:
Orion Type: Twin-spool turboprop Length: 112.3 in (2,852 mm) Diameter: 41 in (1,041 mm) Dry weight: 3,150 lb (1,429 kg) Compressor: 7 stage low pressure, 5 stage high pressure Combustors: Annular combustor with 10 flame tubes Turbine: Single stage high pressure, 3 stage low pressure Fuel type: Kerosene Maximum power output: 5,150 eshp (3,840 kW) (maximum takeoff) Overall pressure ratio: 10:1 Specific fuel consumption: 0.64 lb/eshp/hr Thrust-to-weight ratio: 1.63 eshp/lb (2.68 kW/kg)
Design work on the Proteus started in September 1944, during the course of development the gas generator section was built as a small turbojet which became known as the Bristol Phoebus. This engine was test flown in May 1946 fitted to the bomb bay of an Avro Lincoln, performance was poor due to airflow problems. The centrifugal compressor was redesigned but similar problems were encountered when the Proteus started ground testing on 25 January 1947.
The original Proteus Mk.600 delivered 3,780 hp (2,820 kW), and was going to be used on the early versions of the Britannia and the Saunders-Roe Princess flying-boat. The versions on the Princess were mounted in a large frame driving a single propeller through a gearbox, and were known as the Coupled Proteus. The Coupled Proteus was also intended to be used on the Mk.II versions of the Bristol Brabazon, but this project was cancelled. Only three Princesses were built, only one of which flew, and by the time the Britannia was ready for testing the manufacturer had decided to equip it with the later Mk.700 Proteus instead.
1949 – 3200 shp Proteus in a Filton test hanger
The Proteus was a two spool, reverse-flow gas turbine, similar to the original Whittle engine designs with an extra turbine stage. Because the turbine stages of the inner spool drove no compressor stages, but only the propeller, this engine is sometimes classified as a free turbine.
May 1957
During development, there were severe problems with compressor blades, turbine blades and bearings failing at even low power output levels. This led to the famous quote of Proteus Chief Engineer Frank Owner to Chief Engineer of the Engine Division Stanley Hooker: “You know, Stanley, when we designed the Proteus I decided we should make the engine with the lowest fuel consumption in the world, regardless of its weight and bulk. So far, we have achieved the weight and bulk!”
At this point the Proteus proved to have troubling icing problems, causing the engine and aircraft projects to be delayed while solutions were found. The Mk.705 of 3,900 hp (2,900 kW) was the first version to see widespread production on the Bristol Britannia 100 and some 300 series. The Mk.755 of 4,120 hp (3,070 kW) was used on the 200 series (not built) and other 300’s, and the Mk.765 of 4,445 hp (3,315 kW) was used on the RAF’s Series 250 aircraft.
Part of the Bristol Proteus flight development was a Lincoln with a Phœbus jet engine in the bomb bay. The Phœbus is a pure jet version of the Proteus and air was drawn in through elephant ears.
Lincoln Phœbus mounting
Variants: As with most gas turbine engines of the 1940s, 50s, and 60s the Ministry of Supply allocated the Proteus a designation which was apparently little used. Officially the Proteus was named Bristol BPr.n Proteus
Proteus series 1 (BPr.1)Prototype and early production engines used for development and testing.
Proteus series 2 Initial production versions, renamed as Proteus 600 series engines.
Proteus series 3 The fully developed initial version, re-named as the Proteus 700 series.
Proteus 600 Initial production engines re-named from Proteus series 2.
Proteus 610 The engines used in the Coupled-Proteus installations for the Saunders-Roe Princess airliner.
Proteus 625
Proteus 700
Proteus 705
Proteus 710 The engines slated for use in the Coupled-Proteus installations of the Bristol Brabazon I Mk.II.
Proteus 750
Proteus 755
Proteus 756
Proteus 757
Proteus 758
Proteus 760
Proteus 761
Proteus 762
Proteus 765
Proteus Mk.255 Military engines similar to the Proteus 765, to power the Bristol 253 Britannia C.Mk.1.
Coupled-Proteus 610 Twin Proteus 600 series engines driving contra-rotating propellers through a combining gearbox, developed specifically for the Saunders-Roe SR.45 Princess. Coupled-Proteus 710 Twin Proteus 710 engines driving contra-rotating propellers for the Bristol Brabazon I Mk.II.
Bluebird Proteus A specially modified Proteus 705 with drive shafts at front and rear of the engine to drive front and rear differential gearboxes on Donald Campbell’s Bluebird-Proteus CN7.
Applications: Bristol Britannia Bristol Type 167 Brabazon I Mk.II Saunders-Roe Princess
Specifications:
Proteus Mk.705 Type: Turboprop Length: 113 in (2,870 mm) Diameter: 39.5 in (1,003 mm) Dry weight: 2,850 lb (1293 kg) Compressor: Two-spool 12-stage axial, followed by a single centrifugal stage Combustors: Reverse-flow Turbine: Two-stage power (free turbine), two-stage driving compressor Fuel type: Aviation kerosene Maximum power output: 3,320 shp (2,475 kW) + 1,200 lb (5.33 kN) residual thrust giving 3,780 eshp Overall pressure ratio: 7.2:1 Fuel consumption: 273 Imp gal (1,241 L) /hour Specific fuel consumption: 0.495 lb/h/eshp Power-to-weight ratio: 1.32 eshp/lb
Michel Wibault, the French aircraft designer, had the idea to use vectored thrust for vertical take-off aircraft. This thrust came from four centrifugal compressors driven by a Bristol Orion turboprop, the exhaust from each could be directed by rotating the outlets. Gordon Lewis initially planned an engine with two thrust vectors, driven by the compressor, with forward thrust from a conventional rear exhaust in his initial BE.52 design. The BE.52 design was built around a Bristol Siddeley Orpheus which through a shaft drove the first three stages of a Bristol Olympus engine which had inlet and outlets separate of those of the Orpheus. Work was overseen by Bristol Siddeley’s Technical Director Stanley Hooker.
The Bristol Engine Company began work on the BE.53 Pegasus in 1957. While the BE.52 was a self-contained powerplant and lighter compared to Wibault’s concept, the BE.52 was still complicated and heavy. In the BE.53 the Olympus stages were fitted close to the Orpheus stage; this simplified the inlet ducting and the Olympus stages now supercharged the Orpheus improving the compression ratio.
The engine was designed in isolation for a year, then it was helped greatly by understanding what type of aircraft it was designed for. The team received a supportive letter from Sydney Camm of Hawker in May 1957. Hawker were looking for a Hawker Hunter replacement. The aircraft designer, Ralph Hooper, suggested having the four thrust vectors (originally suggested by Lewis), with hot gases from the rear two. Two thrust vectors did not provide enough lift. The 1957 Defence White Paper, which focused on missiles, and not aircraft, also was not good news.
The further development of the engine then proceeded in tandem with the airframe the Hawker P.1127, which first flew in 1960. The next stage of design and development was then flown in the Kestrel, of which nine were built. This was then developed into the Harrier combat aircraft. The engine was partially supported financially from the Mutual Weapons Development Programme.
The flight testing and engine development received no government funding; the plane’s funding came entirely from Hawker. There was only enough thrust in the first engines to barely lift the plane off the ground because of weight growth problems. Flight tests were conducted when the aircraft was tethered. The first free hover was achieved on 19 November 1960. The first, and difficult, transition from static hover to conventional flight was achieved on 8 September 1961. The RAF was not much of a convert to the VTOL idea, and described the whole project as a toy and a crowd pleaser. The first prototype P1127 made a very heavy landing at the Paris Air Show in 1963.
Series Manufacture and Design and Development improvement to ever higher thrusts of the Pegasus was continued by Bristol engines beyond 1966, which was when Rolls-Royce Ltd bought the Company. A related engine design, the 39,500 lbf (with reheat) Bristol Siddeley BS100 for a supersonic VTOL fighter (the Hawker Siddeley P.1154) was not developed to production as the aircraft project was cancelled in 1965.
The Pegasus vectored-thrust turbofan is a two-shaft design featuring three low pressure (LP) and eight high pressure (HP) compressor stages driven by two LP and two HP turbine stages respectively. Unusually the LP and HP spools rotate in opposite directions to greatly reduce the gyroscopic effects which would otherwise hamper low speed handling. The engine employs a simple thrust vectoring system that uses four swiveling nozzles, giving the Harrier thrust both for lift and forward propulsion, allowing for STOVL flight. This unique design highly contributes to the sustainability and success of its carrier, the Hawker Harrier. Many other designs faced flaws as the lift and forward propulsion functions were split using separate engines. In such a concept once the transition from lift to forward or vice versa is completed, any such engine is reduced to dead weight. I.e. in forward flight lift engines do not need to provide thrust anymore, but still need to be carried by the airframe, consuming valuable fuel, increasing weight, decreasing range and occupying costly space that cannot be used for other purposes anymore. Like fuel, avionics or additional ordnance.
The front two nozzles are fed with air from the LP compressor, the rear with hot (650 °C) jet exhaust. The airflow split is about 60/40 front back. It was critical that the nozzles rotate together. This was achieved by using a pair of air motors fed from the HP (high pressure) compressor, in a fail over configuration, pairs of nozzles connected with, surprisingly, motor-cycle chains.
The Pegasus was also the first turbofan engine to have the initial compressor fan, the zero stage, ahead of the front bearing. This eliminated radial struts and the icing hazard they represent.
The engine is mounted in the centre of the Harrier and as such it is necessary to remove the wing to change the powerplant having already sat the fuselage on trestles; the whole change took a minimum of eight hours.
The maximum take-off thrust available from the Pegasus engine is limited, particularly at the higher ambient temperatures, by the turbine blade temperature. As this temperature cannot reliably be measured, the operating limits are determined by jet pipe temperature. To enable the engine speed and hence thrust to be increased for take-off, water is sprayed into the combustion chamber and turbine to keep the blade temperature down to an acceptable level.
Water for the injection system is contained in a tank located between the bifurcated section of the rear (hot) exhaust duct. The tank contains up to 500 lb (227 kg, 50 imperial gallons) of distilled water. Water flow rate for the required turbine temperature reduction is approximately 35gpm (imperial gallons per minute) for a maximum duration of approximately 90 seconds. The quantity of water carried is sufficient for and appropriate to the particular operational role of the aircraft.
Selection of water injection engine ratings (Lift Wet/Short Lift Wet) results in an increase in the engine speed and jet pipe temperature limits beyond the respective dry (non-injected) ratings (Lift Dry/Short Lift Dry). Upon exhausting the available water supply in the tank, the limits are reset to the ‘dry’ levels. A warning light in the cockpit provides advance warning of water depletion to the pilot.
Over 1,347 engines have been produced and two million operating hours have been logged with the Harriers of the Royal Air Force (RAF), Royal Navy, U.S. Marine Corps and the navies of India, Italy, Spain and Thailand.
The unique Pegasus engine powers all versions of the Harrier family of multi-role military aircraft. In US service, the engine is designated F402. Rolls-Royce licensed Pratt & Whitney to build the Pegasus for US built versions. However Pratt & Whitney never completed any engines, with all new build being manufactured by Rolls-Royce in Bristol, England. The Pegasus was also the planned engine for a number of aircraft projects, among which were the prototypes of the German Dornier Do 31 VSTOL military transport project.
Pegasus 2 Otherwise known as the BE53-3, used in the P.1127, 11,500 lbf (51 kN)
Pegasus 3 Used on the P.1127 prototypes, 13,500 lbf (60 kN)
Pegasus 5 Or BS.53-5 (Bristol-Siddeley 53-3). Used for the Hawker Siddeley Kestrel evaluation aircraft. 15,000 lbf (67 kN)
Pegasus 6 (Mark 101) For first Harriers. 19,000 lbf (85 kN), first flown in 1966 and entered service 1969
Pegasus 10 (Mark 102) For updating first Harriers with more power and used for the AV-8A, 20,500 lbf (91 kN), entering service in 1971.
Pegasus 11 (Mark 103) The Pegasus 11 powered the first generation Harriers, the RAF’s Hawker Siddeley Harrier GR.3, the USMC AV-8A and later the Royal Navy’s Sea Harrier. The Pegasus 11 produced 21,000 lbf (93 kN) and entered service in 1974.
Pegasus 14 (Mark 104) Navalised version of the Pegasus 11 for the Sea Harrier, same as the 11 but some engine components and castings made from corrosion-resistant materials.
Pegasus 11-21/Mk.105/Mk.106 The 11-21 was developed for the second generation Harriers, the USMC AV-8B Harrier II and the BAE Harrier IIs. The original model provided an extra 450 lbf (2.0 kN). The RAF Harriers entered service with the 11-21 Mk.105, the AV-8Bs with F402-RR-406. Depending on time constraints and water injection, between 14,450 lbf (64.3 kN) (max. continuous at 91% RPM) and 21,550 lbf (95.9 kN) (15 s wet at 107% RPM) of lift is available at sea level (including splay loss at 90°). The Mk.106 development was produced for the Sea Harrier FA2 upgrade and generates 21,750 lbf (96.7 kN).
Pegasus 11-61/Mk.107 The 11-61 (aka -408) provides 23,800 lbf (106 kN). This equates to up to 15 percent more thrust at high ambient temperatures, allowing upgraded Harriers to return to an aircraft carrier without having to dump any unused weapons which along with the reduced maintenance reduces total cost of engine use. The RAF/RN upgraded its GR7 fleet to GR9 standard, and part of this process is the upgrade of the Mk.105 engines to Mk.107 standard.
Applications: AV-8B Harrier II BAE Sea Harrier BAE Harrier II Dornier Do 31 Hawker Siddeley Harrier Hawker Siddeley P.1127 Intended application – Armstrong Whitworth AW.681
Specifications:
Pegasus 11-61 Type: Twin-spool turbofan Length: 137 in (3.480 m) Diameter: 48 in (1.219 m) Dry weight: 3,960 lb (1,796 kg) Compressor: 3-stage low pressure, 8-stage high pressure axial flow Combustors: Annular Turbine: 2-stage high pressure, 2-stage low pressure Maximum thrust: 23,800 lbf (106 kN) Overall pressure ratio: 16.3:1 Specific fuel consumption: 0.76 lb/lbf-hr Thrust-to-weight ratio: 6:1
At the end of World War II, the Bristol Engine Company’s major effort was the development of the Hercules and Centaurus radial piston engines. By the end of 1946, the company had only 10 hours of turbojet experience with a small experimental engine called the Phoebus which was the gas generator or core of the Proteus turboprop then in development. In early 1947, the parent Bristol Aeroplane Company submitted a proposal for a medium-range bomber to the same specification B.35/46 which led to the Avro Vulcan and Handley Page Victor. The Bristol design was the Type 172 and was to be powered by four or six Bristol engines of 9,000 lbf (40 kN) thrust.
The thrust required of the new engine, then designated B.E.10 (later Olympus), would initially be 9,000 lbf (40 kN) with growth potential to 12,000 lbf (53 kN). The pressure ratio would be an unheard of 9:1. To achieve this, the initial design used a low pressure (LP) axial compressor and a high pressure (HP) centrifugal compressor, each being driven by its own single-stage turbine. This two-spool design made the compression more manageable, enabled faster engine acceleration (“spool up”), and reduced surge. The design was progressively modified and the centrifugal HP compressor was replaced by an axial HP compressor. This reduced the diameter of the new engine to the design specification of 40 in (100 cm). The Bristol Type 172 was cancelled though development continued for the Avro Vulcan and other projects.
Gas-flow diagram of Olympus Mk 101.The first engine, its development designation being BOl.1 (Bristol Olympus 1), had six LP compressor stages and eight HP stages, each driven by a single-stage turbine. The combustion system was novel in that ten connected flame tubes were housed within a cannular system: a hybrid of separate flame cans and a true annular system. Separate combustion cans would have exceeded the diameter beyond the design limit and a true annular system was considered too advanced.
In 1950, Dr (later Sir) Stanley Hooker was appointed as Chief Engineer of Bristol Aero Engines.
The BOl.1 first ran in May 1950 and produced 9,140 lbf (40.7 kN) thrust. The next development was the BOl.1/2 which produced 9,500 lbf (42 kN) thrust in December 1950. Examples of the similar BOl.1/2A were constructed for US manufacturer Curtiss-Wright which had bought a licence for developing the engine as the TJ-32 or J67. The somewhat revised BOl.1/2B, ran in December 1951 producing 9,750 lbf (43.4 kN) thrust. The engine was by now ready for air testing and the first flight engines, designated Olympus Mk 99, were fitted into a Canberra WD952 which first flew with these engines derated to 8,000 lbf (36 kN) thrust in August 1952. In May 1953, this aircraft reached a world record altitude of 63,668 ft (19,406 m). (Fitted with more powerful Mk 102 engines, the Canberra increased the record to 65,876 ft (20,079 m) in August 1955.)
The Olympus 551 ‘Zephyr’ was a derated and lightened version of the BOl.6 and rated at 13,500 lbf (60 kN) thrust. The engine was the subject of a licence agreement between Bristol Aero Engines and the Curtiss-Wright Corporation – the engine being marketed in the USA as the Curtiss-Wright TJ-38 Zephyr. There were hopes to fit the Olympus 551 to the Avro Type 740 and Bristol Type 200 trijet airliners which did not progress beyond the project stage. Curtiss-Wright also failed to market the engine.
Bristol Aero Engines (formerly Bristol Engine Company) merged with Armstrong Siddeley Motors in 1959 to form Bristol Siddeley Engines Limited (BSEL) which in turn was taken over by Rolls-Royce in 1966.
The performance specification for TSR2 was issued in 1962. It was to be powered by two BSEL Olympus Mk 320 (BOl.22R) engines rated at 30,610 lbf (136.2 kN) with reheat at take-off. The engine was a cutting edge derivative of the Olympus Mk 301 with a Solar-type afterburner.[32] The engine first ran in March 1961 and was test flown in February 1962 underslung Vulcan B1 XA894 and was demonstrated at the Farnborough Air Show in September. In December 1962 during a full power ground run at Filton, the engine blew up after an LP turbine failure, completely destroying its host Vulcan in the subsequent fire.
On its first flight in September 1964 the engines of the TSR-2 were scarcely flightworthy being derated and cleared for one flight. Nevertheless, the risk was deemed acceptable in the political climate of the time. With new engines, the TSR-2 XR219 flew another 23 times before the project was cancelled in 1965.
Plans to civilianise the Olympus go back as far as 1953 with the unveiling of the Avro Atlantic airliner based upon the Vulcan. However, most of the civilian derivatives, except for supersonic airliners, were developed from the BOl.6.
One project that got beyond the drawing board was a supersonic development of the Gloster Javelin, the P370, powered by two BOl.6, 7, or 7SR engines. The design evolved into the P376 with two BOl.21R engines rated at 28,500 lbf (127 kN) with reheat. Eighteen aircraft were ordered in 1955. The project was abandoned the following year.
As early as 1952, Bristols had considered the use of reheat, or afterburning, to augment the thrust of the Olympus. Initially, a system called Bristol Simplifed Reheat was devised which was tested on a Rolls-Royce Derwent V mounted in an Avro Lincoln. Later it was tested on an Orenda engine in Canada and on an Olympus Mk 100 in the Avro Ashton test bed. Fully variable reheat became possible after an agreement with the Solar Aircraft Company of San Diego which manufactured bench units for the Olympus Mks 101 and 102.
As of 2012, the Olympus remains in service as both a marine and industrial gas turbine. It also powered a restored Avro Vulcan XH558.
Variants:
BOl.1/2A
BOl.1/2B
BOl.1/2C
BOl.2
BOl.3 Of all the early initial developments, BOl.2 to BOl.5 (the BOl.5 was never built), perhaps the most significant was the BOl.3. Even before the Vulcan first flew, the Olympus 3 was being suggested as the definitive powerplant for the aircraft. In the event, the ‘original’ Olympus was continuously developed for the Vulcan B1. The BOl.3 was described in 1957 as “a high-ended product intermediate between the Olympus 100 and 200 series.”
BOl.4
BOl.5 not built
BOl.6 (Mk.200)
BOl.7 (Mk.201)
BOl.7SR
BOl.11 (Mk.102)
BOl.12 (Mk.104)
BOl.21 (Mk.301)
BOl.21R
BOl.22R (Mk.320)
Olympus Mk 100 (BOl.1/2B) Similar to Olympus Mk 99 rated at 9,250 lbf (41.1 kN) thrust for second Vulcan prototype VX777. First flew September 1953.
Olympus Mk 101 (BOl.1/2C) Larger turbine, 11,000 lbf (49 kN) thrust for initial production Vulcan B1 aircraft. First flew (XA889) February 1955.
Olympus Mk 102 (BOl.11) Additional zero stage on LP compressor, 12,000 lbf (53 kN) thrust for later production Vulcan B1 aircraft.
Olympus Mk 104 (BOl.12) Designation for Olympus Mk 102 modified on overhaul with new turbine and burners, 13,000 lbf (58 kN) thrust initially, 13,500 lbf (60 kN) thrust on uprating, standard on Vulcan B1A.
‘Olympus 106’ Used to describe the development engine for the Olympus 200 (BOl.6). Possibly a corruption of BOl.6 (Olympus 6).
The initial design of the second generation ‘Olympus 6’ began in 1952. This was a major redesign with five LP and seven HP compressor stages and a canullar combustor with eight interconected flame tubes. In spite of a much greater mass flow, the size and weight of the BOl.6 was little different to earlier models.
Rival manufacturers Rolls-Royce lobbied very hard to have its Conway engine installed in the Vulcan B2 to achieve commonality with the Victor B2. As a consequence, Bristols undertook to complete development using company funds and peg the price to that of its fully government-funded rival.
Olympus Mk 97 This early engine tested an early annular combustion chamber. It was test flown on Bristol’s Avro Ashton test bed WB493.
Olympus Mk 202 Disputed. Either Olympus Mk 201 modified with rapid air starter, or Olympus Mk 201 with redesigned oil separator breathing system. This was the definitive ‘200 series’ engine fitted to Vulcans not fitted with the Mk 301. The restored Vulcan XH558 is fitted with Olympus Mk 202 engines.
‘Olympus Mk 203’ Very occasional reference to this elusive mark of engine can be found in some official Air Publications relating to the Vulcan B2. It is also noted in a manufacturer’s archived document dated circa 1960.
Olympus Mk 301 (BOl.21) Additional zero stage on LP compressor. 20,000 lbf (89 kN) thrust. Later Vulcan B2 aircraft plus nine earlier aircraft retrofitted. Later derated to 18,000 lbf (80 kN) thrust. Restored to original rating for Operation Black Buck.
Olympus 510 series With a thrust in the region of 15,000 lbf (67 kN) to 19,000 lbf (85 kN), the 510 series were civilianised versions of the BOl.6. A team was sent to Boeing at Seattle to promote the engine in 1956 but without success.
Olympus 551
Specifications:
Olympus 101 Type: Axial flow two-spool turbojet Length: 152.2 in (387 cm) Diameter: 40 in (100 cm) Dry weight: 3,615 lb (1,640 kg) Compressor: Axial 6 LP pressure stages, 8 HP stages Combustors: Cannular 10 flame tubes Turbine: HP single stage, LP single stage Fuel type: AVTUR or AVTAG Maximum thrust: 11,000 lbf (49 kN) Specific fuel consumption: .817 Power-to-weight ratio: 3.04:1
The last of the ‘Bristol’ aircraft was the purely research aeroplane, the Type 221. With the B.188, they furnished valuable information on the structural and aerodynamic problems associated with supersonic flight. The Type 221, first flown was on May 1, 1964, was a modified version of the record breaking Fairey Delta 2 and used to investigate the handling and control characteristics of the slender ogival wing, which was again to feature in the Concorde.
Engine: 1 x 5000kg Wingspan: 7.62 m / 25 ft 0 in Length: 17.55 m / 57 ft 7 in Height: 3.96 m / 12 ft 12 in Wing area: 46.82 sq.m / 503.97 sq ft Max. speed: 1707 km/h / 1061 mph Crew: 1
In the mid 1950s Bristol Aircraft Ltd began work on a turbine-powered helicopter using a B.171 Syvamore Mk 3 with an increased fin area. Under the name Bristol 203 it was to be an 11-seat machine and parts from the incomplete 179th and 180th Sycamore airframes were used in the prototype machine. This project was abandoned when the company was taken over by Westland, although some of its finer points were later incorporated in the Lynx.
In the late 1950s the Bristol aircraft design team, under the leadership of Dr Archibald E. Russell, was awarded important MoS contracts for design and feasibility studies in the development of a supersonic transport. After an outline design for a thin delta wing with pencil fuselage had been accepted, the Bristol Type 198 was projected. This would have been a trans Atlantic range delta aircraft powered by six Bristol Olympus engines. The government decided that this 380,000 lb machine was too heavy and asked for a smaller design, capable of carrying 100 passengers across the Atlantic, with a maximum weight of 250,0001b. This resulted in the Type 223 which formed the basis for the British contribution to the collaborative venture with France which was agreed in November 1962 and resulted in Concorde. Concorde 002, G BSST, made its inaugural flight from Filton on 9 April 1969
Undertaken by Bristol in response to Royal Navy and Canadian naval specifications were the models 191 and 193.
The Bristol 191 was a ship-based development of Type 173 with modified fuselage, u/c etc.
The Bristol 192 was the production version of Model 191 for RAF use with two cabin windows only, starboard cargo hatch, cargo hoist beneath fuselage, large anhedralled tailplane and powered by two 1465shp Napier Gazelle 2 turboshafts, derated to 920shp. In the initial configuration, the 192 had a purely manual system of control and wooden rotor blades but power controls and metal blades were standardized on the fifth prototype built in 1960. The prototype Type 192 (XG447) first flying on 5 July 1958 at Westonsuper-Mare, was demonstrated at the Farnborough air show in September 1952. That year, three pre-production aircraft were assigned to the RAF for a series of trials for which they were based at Odiham.
As the Westland Belvedere this entered service with the Royal Air Force, though this was only after the 191 and 193 had been cancelled by the RAF and Royal Canadian Air Force respectively.
Twenty-six of these helicopters were ordered and used for some years for military transport, not only in the United Kingdom, but also in the Middle and Far East. The Belvedere was withdrawn from service in March 1969.
The production Bristol 192s had an all-metal, skinned fuselage and an anhedral tailplane, compared with the dihedral one of the Type 173. The two rotors had four metal blades and the front wheels of the fixed quadricycle landing gear were self-castoring. The helicopter’s maximum capacity was 30 seats or 2700kg internal payload. The instrumentation also permitted night flying.
As the 192C it was tested by BEA and offered its 24 passengers a unique high-speed service between London and Paris. British European Airways leased a Belvedere briefly but never used it in commercial service.
On May 30, 1961, C T D Hosegood flew from London to Paris in 1 hour 41 min 28 sec and on June 2, 1961, from Paris to London in 1 hour 40 mm 55 sec. This is the equivalent of 202.32km/h outwards and 203.51 km/h on the return flight.
Bristol B 192 Belvedere HC Mk I Engines: 2 x Napier Gazelle 2, 1627 shp, 1092kW Fuselage length: 54.134 ft / 16.5 m Length with rotors turning: 27.36m Height: 17.388 ft / 5.3 m Rotor diameter: 48.885 ft / 14.91 m Max take off weight: 18522.0 lbs / 8400.0 kg Empty weight: 5277kg Max. speed: 119 kts / 220 km/h Service ceiling: 13123 ft / 4000 m Range: 378 nm / 700 km Crew: 2 + 25 PAX / 2700kg
The Bristol 188 was designed to research structures for sustained supersonic flight, particularly in support of the Avro 730 reconnaissance aircraft. This required the aircraft to ‘soak’ at Mach 2.6 for at least 30 minutes. The Bristol Type 188 research aircraft XF962 was built for high speed research. Two examples were built, constructed mainly of stainless steel and highly polished natural metal finish. Powered by two de Havilland Gyron Junior turbojets, the type first flew on 29 April 1963 and subsequently attained Mach 1.88 at 36,000 ft. However, the 188 had an extremely high fuel consumption and was only able to remain airborne for about 25 minutes.
Take-off speed was nearly 483km/h, but in all other respects the 188’s speed was slower than desired, being able to achieve Mach 2.0 for only a couple of minutes. The whole project cost a huge GBP20 million and failed to achieve its objectives. It was wound down rather than develop the engines further. Test pilot Godfrey Auty was voted the ‘man most likely to eject in the coming year’ by his peers but never had to.
In 1964 the B.188 was indefinitely grounded, less than two-years after the first of two flew. A third never reached flight. The most expensive research aircraft built in Britain, the B.188 which a list of projects up to Mach 3 was to be flying for 12 to 15 years. For some time, one plane was cannibalised to support another.
B.188 Engines: 2 x de Havilland Gyron Junior DGJ.10R turbojets, 6350kg Wingspan: 10.69 m / 35 ft 1 in Length: 21.64 m / 70 ft 12 in Height: 4.06 m / 13 ft 4 in Wing area: 36.79 sq.m / 396.00 sq ft Max. speed: 1932 km/h / 1201 mph Crew: 1
The Type 175 began as a Medium Range Empire (MRE) design to meet BOAC requirements set down in MoS Specifica¬tion 2/47. Designed to carry 32-36 passengers and be powered by four Bristol Centaurus 662 sleeve-valve engines, the aircraft’s size was soon increased and consideration given to the installation of Bristol Proteus turbines or Napier Nomad compound engines. After some delay, in June 1948 the Ministry of Supply ordered three Centaurus-powered prototypes but stipulated that the second and third should be capable of conversion to Proteus-engined aircraft. When the first prototype emerged in 1952 it was a much bigger aeroplane with accommodation for more than 80 passengers and powered by Proteus 625 engines. Prototypes were ordered in February 1948 and the first of these was airborne at Filton on 16 August 1952, powered by Bristol’s new Proteus turboprop.
The second prototype was lost after only 51hr flying and a major engine fault delayed entry into service with BOAC until February 1957. On 1 February 1957 BOAC began operating Britannia 102 with 2,906kW Proteus 705 and up to 90 seats on its London-Johannesburg services.
A number of versions were developed from the Series 100 aircraft and on 19 December 1957, BOAC began the first turbine-powered North Atlantic service when it put Britannia 312 on the London-New York route. These were 3.12m longer, had accommodation for up to 139 passengers, were powered by 3,070kW Proteus 755 and had a 13,608kg increase in max weight. On the day that BOAC introduced Britannias on the North Atlantic, El Al flew a Britannia 10,328km non-stop from New York to Tel Aviv.
The Bristol Britannia entered RAF Transport Command service with No.99 Squadron, at Lyneham, Wiltshire, in mid-1959. As Britannia C.1, twenty Britannia 250 were operated with strengthened floor and large freight loading doors. Three Britannia C.2s were purchased by the Ministry of Supply for use on trooping flights.
The Britannia 310 was ordered by BOAC, El Al, Hunting Clan, Canadian Pacific Airlines and Cubana.
Britannia 310
Only 85 Britannias were built at Filton and by Shorts at Belfast.
Canadair developed the Britannia design into the military CL-28 Argus and CL-44 Yukon and the CL-44 series of passenger and cargo aircraft.
100 Series 90 passenger airliner All built at Filton Engines: four Bristol Proteus 705, 4,400 h.p. Length: 114 feet Height: 36 feet 8 inches Wing Span: 142 feet 3 inches Weight (empty): 88,000lbs Weight (all-up): 155,000lbs Range: 3,450 miles
101 – Two prototypes, initially powered by Proteus 625, later 705 102 – 25 ordered by BOAC. The last ten were cancelled in favour of the 300 series.
200 Series All-cargo stretched version of the 100 series, with an extra 10 ft in length. Five options from BOAC, but cancelled in favour of the 310. None built.
250 Series As 200 series, but mixed passenger and freight Length: 124 feet 3 inches Height: 37 feet 6 inches Wing Span: 142 feet 3 inches Weight (empty): 90,500lbs (90,600lbs for 253) Weight (all-up): 185,000lbs Range: 2,268 miles
252 – Three ordered by Royal Air Force and given the designation C Mark 2. All built at Belfast. 253 – 22 ordered by Royal Air Force, with designation C Mark 1. All but the last five were built at Belfast, the remainder were built at Filton
300 Series As 200 series, by passenger only. Capable of carrying up to 139 passengers. Engines: 4 x 4,400 h.p. Bristol Siddeley Proteus 705 turboprop Length: 124 feet 3 inches (37.89 m.) Height: 37 feet 6 inches Wing Span: 142 feet 3 inches (43.38 m) Weight (empty): 92,500lbs Weight (all-up): 185,000lbs Econ cruise: 355 m.p.h. (570 kph) Range: 3,496 miles Range 4,268 miles (6,869 km.) with max. payload of 28,000 lb (12,700 kg) Crew: 9 Pax cap: 133
301 – one prototype, built at Filton 302 – Ten ordered by BOAC. Order cancelled in favour of 305 Series, later 310 series. Two were completed, but not delivered. Both were built at Belfast.
305 Series As 300, but with increased fuel capacity Length: 124 feet 3 inches Height: 37 feet 6 inches Wing Span: 142 feet 3 inches Weight (empty): 90,000lbs Weight (all-up): 185,000lbs Range: 4,268 miles
306 – 1 built, leased to El Al. built at Belfast 307 – 2 ordered by Air Charter. One was a conversion of the sole 306, the other was built at Belfast. 307F – 1960’s conversion of 307 to freighter (both Series 307 aircraft converted) 308 – 2 ordered by Transcontinental, built at Belfast. 308F – 1960’s conversion of 308 to freighter (both Series 308 aircraft were converted) 309 – 1 ordered by Ghana Airways, built at Belfast.
310 Series Initially known as 300LR. As 305 series, but with strengthened fuselage skin and undercarriage. Engines: 4 x Bristol Proteus, 4120 shp Length: 124 feet 3 inches (37.89 m) Height: 37 feet 6 inches Wing Span: 142 feet 3 inches (43.38 m) Weight (empty): 82,500lbs Weight (all-up): 185,000lbs Range: 4,268 miles Max level speed: 385 mph (616 kph)
311 – one prototype, built at Filton. 312 – 19 ordered by BOAC, all built at Filton. Engine : 4 x Proteus 755, 4064 shp Length: 124.245 ft / 37.87 m Height: 37.5 ft / 11.43 m Wingspan : 142.224 ft / 43.35 m Max take off weight : 185030.4 lb / 83914.0 kg Max. speed : 345 kts / 639 km/h Service ceiling : 26247 ft / 8000 m Range : 5004 nm / 9268 km Crew : 5 + 133 PAX
312F – 1960’s conversion of 312 to freighter (five converted) 313 – Four ordered by El Al, all built at Filton. 314 – Six ordered by Canadian Pacific, all bar one built at Belfast. 317 – Two ordered by Hunting-Clan Air Transport, all built at Filton. 318 – Four ordered by Cubana, all built at Filton. 320 Series – as Series 310, with a few modifications, giving increased maximum range. Length: 124 feet 3 inches Height: 37 feet 6 inches Wing Span: 142 feet 3 inches Weight (empty): 86,400lbs Weight (all-up): 185,000lbs Range: 4,268 miles
