Bristol F.2 Fighter
|Bristol F.2 Fighter|
|The Shuttleworth Collection's Bristol F.2B Fighter|
|Role||Biplane fighter aircraft|
|Manufacturer||British and Colonial Aeroplane Company|
|First flight||9 September 1916|
|Primary users||Royal Flying Corps
Polish Air Force
The Bristol F.2 Fighter was a British two-seat biplane fighter and reconnaissance aircraft of the First World War developed by Frank Barnwell at the Bristol Aeroplane Company. It is often simply called the Bristol Fighter, other popular names include the "Brisfit" or "Biff".
Although the type was intended initially as a replacement for the pre-war Royal Aircraft Factory B.E.2c, the newly-available Rolls-Royce Falcon inline engine gave it the performance of a two seat fighter.
Despite a disastrous start to its career, the definitive F.2B version proved to be an agile aircraft that was able to hold its own against opposing single-seat fighters; its robust design ensured that it remained in military service into the 1930s. Many surplus aircraft were registered for civilian use, and dedicated civilian versions proved popular.
- 1 Development
- 2 Operational history
- 3 Operators
- 4 Survivors
- 5 Specifications (F.2B)
- 6 See also
- 7 References
- 8 External links
By Autumn 1915, the Royal Flying Corps (RFC) had identified the need for an effective replacement for the pre-war Royal Aircraft Factory B.E.2c, and had dispatched a specification for a new aerial reconnaissance and artillery spotting aircraft back to the United Kingdom. Among other attributes and performance requirements, emphasis was placed upon the aircraft's ability to defend itself in aerial combat.
Various submissions were made to meet the RCF's specification; the Royal Aircraft Factory responded with its R.E.8 design,  while the Armstrong Whitworth Company produced the design that eventually emerged as the F.K.8. In March 1916, Frank Barnwell of the Bristol Aeroplane Company, commenced work on a new design also intended to serve as a possible replacement for the aging B.E.2. This initially took two forms, the Type 9 R.2A, to be powered by the 120 hp Beardmore engine, and the very similar Type 9A R.2B, powered by the 150 hp Hispano Suiza. Both designs featured the mounting of the fuselage between the wings, with a gap between the lower longerons and the wing, along with a substantial part of the vertical tail surfaces being located beneath the fuselage. These features were intended to optimize the field of fire for the observer; the positioning of the fuselage also resulted in the upper wing obscuring less of the pilot's field of view. The crew positions were deliberately placed as closely together as possible, to optimise communication between the pilot and observer.
Before either the R.2A or R.2B could be constructed, the new 190 hp (142 kW) Rolls-Royce Falcon inline engine became available; Barnwell now drafted a third revision of his design around the new engine, with its decidedly superior power/weight ratio. The anticipated improvement in performance changed the emphasis in its intended operational use; it was now seen as a replacement for the F.E.2d and Sopwith 1½ Strutter two-seat fighters rather than a competitor with the pedestrian reconnaissance designs that were to replace the B.E.2. The resulting Type 12 F.2A, was a two-bay equal-span biplane, closely based on the R.2 and R.2A designs.
In July 1916, work commenced on the construction of a pair of prototypes; on 28 August 1916, an initial contract was awarded for 50 production aircraft. On 9 September 1916, the first prototype performed its maiden flight, powered by the Falcon engine. The first prototype was fitted with B.E.2d wings (Bristol were major contractors for the type) to save time; its lower wings were attached to an open wing-anchorage frame and had end-plates at the wing roots. On 25 October 1916, the second prototype was completed, which was powered by a Hispano-Suiza engine, and otherwise differed from the first prototype by its tail-skid being integrated into the base of the rudder.
Early on, it was found that the radiator arrangement used on the first prototype obscured a portion of the pilot's field of view, and thus the nose was redesigned around a new circular-shaped frontal radiator housed within a cowling. Other changes to the first prototype during flight testing including the elimination of the end-plates from the lower wing roots and a shallow coaming being fitted around the cockpits. Between 16 and 18 October 1916, the first prototype participated in official trials held at the Central Flying School, Upavon; during these tests, the aircraft was fitted with both a four-bladed 9 ft 2 in propeller and a two-bladed 9 ft 8 in propeller. The first prototype was also outfitted with a Scarff ring mounting near the rear cockpit and an Aldis optical sight prior to its arrival at the experimental armament station at Orfordness.
Only 52 F.2A aircraft, which were broadly similar to the configuration of the first prototype, were manufactured prior to production being switched to what would become the definitive model of the Bristol Fighter, the Bristol Type 14 F.2B. On 25 October 1916, the F.2B variant performed its first flight. The first 150 or so aircraft were powered by either the Falcon I or Falcon II engine, however, the remainder were equipped with the 275 hp (205 kW) Falcon III engine and could reach a maximum speed of 123 mph (198 km/h). The F.2B was over 10 mph (16 km/h) faster than the F.2A and was three minutes faster at reaching 10,000 ft (3,000 m).
The Bristol F.2 Fighter was armed in what had by then become the standard weapons configuration for a British two-seater military aircraft: one synchronised fixed, forward-firing .303 in (7.7 mm) Vickers machine gun, along with a single flexible .303 in (7.7 mm) Lewis Gun mounted on a Scarff ring in the observer's rear cockpit.
The F.2B variant often carried a second Lewis gun on the rear cockpit mounting, although observers found the weight of the twin Lewis gun mounting difficult to handle in the high altitudes at which combat increasingly took place in the last year of the war, many preferring to retain a single gun.
A number of attempts were made to add forward firing Lewis guns on a Foster mounting or similar on the upper wing - either instead of, or in addition to the Vickers gun. Among other problems this caused interference with the pilot's compass, which was mounted on the trailing edge of the upper wing. Some F.2Bs were fitted with a Lewis gun offset to starboard to minimise this effect.
Rolls-Royce aero engines of all types were in chronic short supply at this time, and the Falcon was no exception, which was in part a result of indecisive officials and delays encountered. This shortage of engines frustrated plans to increase production and for the Bristol Fighter to become the standard British two-seater, replacing the R.E.8 and F.K.8; there simply were not enough Falcons available for the amount of aircraft sought. Accordingly, efforts were made to find an available alternative powerplant that was both sufficiently powerful and reliable to power the Fighter.
The Type 15 was fitted with a 200 hp (150 kW) Sunbeam Arab piston engine. At one point, the Arab engine was specified to be used on all Fighters produced by sub-contractors under licence, while Bristol-built Fighters would continue to use the Falcon engine. As it had become clear that the Hispano-Suiza engine could not be produced in sufficient quantities either, it was decided to standardise on the Arab engine to power the type. To offset the reduction in performed caused by this engine, it was planned for the majority of Arab-powered Fighters to stick to corps-reconnaissance duties and avoid fighter-reconnaissance operations.
Unfortunately, the Arab engine proved to be problematic, having been found to be suffering from serious weaknesses in the designs of the cylinder and crank-chamber, leading to considerable delays in production. It also suffered from chronic and severe levels of vibration, while the cooling system also required repeated modification as well; as a result, the "Arab Bristol" never managed to become a viable combination, in spite of prolonged development. A few Arab-engined Bristols were at the front late on in the war, but most British reconnaissance squadrons soldiered on with the R.E.8 and F.K.8 until the end of hostilities.
The Type 16 was fitted with a 200 hp (150 kW) Hispano-Suiza engine. This worked better than the Arab, but the Hispano-Suiza's availability was no better than of the Falcon, and those that were available were required for the S.E.5a and Sopwith Dolphin. The 300 hp (220 kW) version of the Hispano-Suiza, suggested for the Type 17, was not available in quantity before the end of the war.
Other engines tried or suggested for the F.2B were the 200 hp (150 kW) RAF 4d, the 180 hp (130 kW) Wolseley Viper and the 230 hp (170 kW) Siddeley Puma. Trials of the Puma engine were carried out in February 1918, which was found to have marginally better performance than the Hispano-Suiza and Arab engines, but proved difficult to install, while suffering some issues as well. In September 1918, trials of a high-compression model of the Puma engine were performed, but were found to have no significant performance benefit and were not pursued.
The Type 22 was a proposed version adapted for a radial or rotary engine; either a 200 hp (150 kW) Salmson radial, a 300 hp (220 kW) ABC Dragonfly radial (Type 22A), or a 230 hp (170 kW) Bentley B.R.2 rotary (Type 22B). The type number was eventually used for the Bristol F.2C Badger, a totally new design.
The "All-Metal Bristol Fighter"
The Bristol M.R.1 is often described as an "all-metal version of the F.2b". In fact it was a totally new design – although it shared the characteristic of having the fuselage positioned between the upper and lower wing. Two prototypes were built, the first flying on 23 October 1917, but the M.R.1 never entered mass production.
Upon America's entry into the First World War, the Aviation Section, U.S. Signal Corps of the United States Army lacked any competitive combat aircraft either in inventory or under construction at that time. On 1 August 1917, General John J. Pershing, the commander of the American Expeditionary Forces on the Western Front, issued his personal recommendation for the Bristol Fighter to be domestically manufactured in the United States, leading to plans being assembled for the development and production of an American version of the Fighter by the United States Army Engineering Division.
Original proposals for the American production had the 200 hp (149 kW) Hispano-Suiza engine. On 5 September 1917, a single F.2B Fighter was delivered to the Smithsonian Institution, Washington, United States. However, efforts to commence production in the United States floundered due to the mistaken decision by Colonel V.E. Clark of the Bolling Commission to redesign the Fighter to be powered with the 400 hp (298 kW) Liberty L-12 engine. The Liberty was a totally unsuitable engine for the Bristol, as it was far too heavy and bulky, and the resulting aircraft had a nose-heavy attitude during flight.
A contract for 1,000 aircraft was placed initially with the Fisher Body Corporation, but this was subsequently cancelled and reallocated to the Curtiss Aeroplane and Motor Company instead. On 7 December 1917, the order was doubled to 2,000 aircraft. On 25 January 1918, the first aircraft, which was given the designation U.S.A 0-1, was completed, despite the warnings and misgivings of Barnwell, who was not satisfied by some of the modifications made, particularly in the use of the Liberty L-12 engine. According to Bruce, misdirections attributed to Major E.J. Hall of the U.S. Signals Corps had led to roughly 1,400 production drawings produced by Curtiss being rendered obsolete. The reputation of the type was also tarnished by three early crashes, although these had been attributed to one count of pilot error and two counts of faulty workmanship.
Efforts to change the powerplant of American-built Bristol Fighters to the more suitable Liberty 8 or the 300 hp (224 kW) Wright-Hisso came up against political as well as technical problems. By July 1918, the only specimen of the American-built Hispano-Suiza engine had been installed into a Fighter; the combination soon gained the favour of the U.S. Air Board, who suggested to Curtiss that all work on the Liberty L-12 version of the aircraft be abandoned in favour of the Hispano-Suiza version. In spite of protests by Curtiss, the contracts for the U.S.A. 0-1 were terminated, leading to only a pair of prototypes and 25 production aircraft out of the planned 2,000 aircraft were constructed.
It was then suggested by W. C. Potter, Assistant Director of Aircraft Production, that the original Bristol Fighter should be produced exactly as per Barnwell's original designs for it, save for the use of either the Liberty 8 or Hispano-Suiza engine. Potter's proposal was overlooked, instead it was decided to produce eight aircraft, four being fitted with the Hispano-Suiza engine, designated as the Engineering Division USB-1A, and four being powered by the Liberty L-8 engine, designated as the Engineering Division USB-1B. However, only one each of each were built.
When fitted with a new plywood semi-monocoque fuselage designed by the Engineering Division of the US Army Air Service and powered by a Wright-Hispano engine, the US-built Bristol Fighter was designated as the XB-1A and XB-1B. The XB-1A was armed with a pair of Marlin machine guns at the pilot's position while the XB-1B was armed with a pair of Browning machine guns instead. These aircraft were reportedly intended for use as night observation aircraft. Three prototypes were built by the Engineering division at McCook Field, with a further 44 aircraft built by the Dayton-Wright Company. According to Bruce, despite substantial efforts to differentiate and modify the aircraft's design, none of the American-built Fighters possessed any improvement in performance over the original Bristol Fighter.
Postwar developments of the F.2B included the Type 14 F.2B Mk II, a two-seat army co-operation biplane, fitted with desert equipment and a tropical cooling system, which first flew in December 1919. 435 were built. The Type 96 Fighter Mk III and Type 96A Fighter Mk VI were structurally strengthened aircraft, of which 50 were built in 1926–1927.
Surplus F.2Bs were modified for civilian use. The Bristol Tourer was an F.2B fitted with a Siddeley Puma engine in place of the Falcon and with the cockpits enclosed by canopies. The Tourer had a maximum speed of 128 mph (206 km/h).
Days prior to the Christmas 1916, the first deliveries of production F.2A Fighters were completed, No. 48 Squadron being the first operational unit of the Royal Flying Corps (RFC) to receive the type. On 8 March 1917, No.48 and its Fighters were deployed to France in preparation for action on the Western Front; Hugh Trenchard, 1st Viscount Trenchard was keen to get the F.2A Fighter and other newly introduced aircraft ready for the upcoming Second Battle of Arras, aiming to surprise German forces with the hitherto unknown type, and this led to restriction on its deployment prior to the battle to avoid alerting the Germans to the presence of the Fighter.
Accordingly, the first offensive action that involved the F.2A Fighter crossing the frontline occurred on 5 April 1917, which had been deliberately timed to coincide with the British offensive at Arras. The very first F.2A patrol of six aircraft from No. 48 Squadron RFC, led by Victoria Cross recipient William Leefe Robinson, ran into five Albatros D.IIIs from Jasta 11 led by Manfred von Richthofen. Four out of the six F.2As were shot down – including Robinson's; he was captured – and a fifth was badly damaged.
Other early experiences with the F.2A Fighter contributed to doubts over its effectiveness. The month in which the type had been introduced to offensive operation became known as Bloody April: casualties were high throughout the RFC, and initially the Bristol fighter proved to be no exception. At this period, contemporary two-seater aircraft were far less nimble than fighter aircraft, and many types lacked the structural strength to carry out the aggressive manoeuvres needed for dogfighting. The first "Brisfit" aircrews were accustomed to the standard doctrine of maintaining formation and using the crossfire of the observers' guns to counter enemy fighter aircraft.
Pilots soon realised that the Bristol Fighter was a strong and agile aircraft, capable of manoeuvring with single-seat fighters, despite some rumours that the type lacked the necessary structural strength to be flown as a fighter. While its fixed forward-firing machine gun could be used as the primary weapon, the observer would be able to use his flexible, rear-mounted gun to provide protection for the aircraft's tail. Flown in this manner, the Bristol Fighter achieved a 'remarkable' level of success and proved to be a formidable opponent for German fighters.
From May 1917 onwards, the definitive F.2B Fighter quickly supplanted and replaced the earlier F.2A model. In July 1917, the War Office decided to adopt the F.2B Fighter as the equipment of all fighter-reconnaissance squadrons, leading to a significant increase in production. Despite the issuing of contracts for further large batches of aircraft, it was apparent that the rate of production could not keep up with demand for the type.
Perhaps one of the best known flying aces to use the type was Canadian Andrew Edward McKeever, and his regular observer L.F. Powell. By the end of 1917, McKeever had accumulated 30 shoot-downs of enemy aircraft, while Powell had achieved eight aerial kills, while operating the Fighter. McKeever later became a flying instructor stationed in England before becoming the commanding officer of No. 1 Squadron of the newly formed Royal Canadian Air Force (RCAF), where he continued to use the Fighter as his personal aircraft, which was later transferred to Canada.
Towards the final months of the conflict, the Bristol Fighter was used in a pioneering new capability in the form of radio communications; No. 11 Squadron was the first such squadron to be equipped. When equipped with this system, only the flight commander's Fighter would be equipped with a transmitter while others were outfitted with receivers, allowing for one-way communication of orders; as the trailing aerials employed needed to be wound in prior to aerial combat, this requirement reduced the usefulness of the system. The Fighter also participated in experiments held by the Royal Aircraft Establishment (RAE) into the use of parachutes, resulting in several aircraft being modified to carry static-line parachutes within the underside of the fuselage; these trials continued following the signing of the Armistice.
In September and October 1917, orders for 1,600 F.2B Fighters were placed; by the end of the First World War, the Royal Air Force (RAF) had a total of 1,583 F.2Bs in squadron service; it was in service with six reconnaissance squadrons stationed in France and five Home Defence squadrons, while further squadrons operating the type were positioned in the Middle East and Italy. A total of 5,329 aircraft were eventually constructed, mostly by Bristol but also by Standard Motors, Armstrong Whitworth and even the Cunard Steamship Company. According to Bruce, by the end of the Armistice of 11 November 1918, which brought an end to the conflict, the "Bristol Fighter ended the war supreme in its class".
Following the end of the First World War, the F.2B Fighter was soon adopted by the RAF as its standard army cooperation. The type continued to operate in army cooperation and light bombing roles throughout the British Empire, in particular the Middle East, India and China. In line with this role, which led to its use under high-temperature conditions, Bristol introduced models of the Fighter equipped with 'tropical' radiators that could better handle operations within higher temperatures and other furnishings for desert equipment. There had also been considerations made into deploying the Fighter as a carrier-based aircraft, which led to an engineless airframe participating in immersion trials in November 1918 and a single aircraft was used in deck landing tests, reportedly held onboard HMS Eagle.
It was not until 1932 that the F.2B was finally withdrawn from RAF service, the last "Brisfit" unit being No. 20 Squadron RAF stationed in India. The type lasted a further three years in New Zealand. Aircraft that were deemed surplus to requirements were allocated to ADC Aircraft, a British company established to act as a reseller for wartime aircraft, who proceeded to sell on large quantities of Fighters to other nations, normally to military operators. Bristol also continued to manufacture the type for some time. During the 1920s, Bristol proceeded to develop and introduce numerous variants and derivatives of the Fighter, typically capable of carrying higher loads, revised tail units, and strengthened undercarriages.
The F.2B Fighter was adopted by the New Zealand Permanent Air Force and the Royal Australian Air Force (RAAF), as well as with the air forces of Belgium, Canada, Ireland, Greece, Mexico, Norway, Peru, Spain and Sweden. According to Bruce, relatively few Fighters entered service with the air force's of the various Commonwealth nations, greater quantities having been sold to other nations. Both new-build and reconditioned aircraft were sold by Bristol, while ADC Aircraft also served as a reseller of the type. Belgium purchased several ADC aircraft, and later arranged to produce the Fighter under licence at Sociétés Anonyme Belge de Constructions Aéronautiques (SABCA).
In 1920, Poland bought 107 Bristol Fighters, thus becoming the second largest user of this type (105 with Hispano-Suiza 300 hp/220 kW engines, two with RR Falcon III). It was the most numerous Polish aircraft type at that time. Forty Fighters were used during the Polish-Soviet war from July 1920, among others in the Battle of Warsaw, performing both reconnaissance and close air support missions. The rest of the order became operational only after the end of hostilities. During the war, a pair were shot down by ground fire, while another was captured by the Soviets and several more were lost in crashes. Survivors of the conflict continued in Polish service in the reconnaissance and training roles up until 1932.
- Afghan Air Force operated three aircraft from 1919 and retired them by 1929.
- Australian Flying Corps operated the Bristol Fighter from 1917 to 1918.
- Irish Air Service
- Irish Air Corps
- New Zealand
- New Zealand Permanent Air Force operated seven Bristol F.2B Fighters from 1919 to 1936. During its 16 years of service with the NZPAF, it was used as an Army Co-operation, aerial-survey and advanced training aircraft.
- Soviet Air Force - Two aircraft.
- Royal Swedish Air Force – One aircraft only
- Royal Yugoslav Air Force – One aircraft only.
- United Kingdom
Airworthy- There are three airworthy Bristol Fighters in 2007, (and several replicas):
- The Shuttleworth Collection contains one airworthy F.2B Fighter, identity D8096, that still flies during the English summer.
- The Canada Aviation and Space Museum, in Rockcliffe, Ontario, owns a second example, D-7889.
- The New Zealand film director Peter Jackson owns D-8084, which flies from the Hood Aerodrome, In Masterton, New Zealand. The Aviation Heritage Centre, In Omaka, N.Z., holds a second, original fuselage.
On static display-
Substantially original aircraft are on static display at the:
- Royal Air Force Museum London, UK
- Imperial War Museum Duxford, UK
- Museo del Aire, Madrid, Spain
- Musée Royal de l'Armée, Brussels, Belgium
- Polish Aviation Museum, Kraków.
- In 2016, Aerospace Bristol, Filton Airfield, Bristol, UK, purchased the example owned by the Ross Walton Family private collection in USA for restoration and display in its new museum.
Engineers at Rolls-Royce, Airbus and GKN Aerospace-Filton have also built a full-scale replica F.2B in celebration of 100 years of aircraft manufacture at Filton Bristol, where the original fighters were designed and built.
Data from Aircraft Profile No. 21: The Bristol Fighter
- Crew: 2 (pilot & observer/gunner)
- Length: 25 ft 10 in (7.87 m)
- Wingspan: 39 ft 3 in (11.96 m)
- Height: 9 ft 9 in (2.97 m)
- Wing area: 405 ft² (37.62 m²)
- Empty weight: 2,145 lb (975 kg)
- Max. takeoff weight: 3,243 lb (1,474 kg)
- Powerplant: 1 × Rolls-Royce Falcon III liquid-cooled V12 engine, 275 hp (205 kW)
- Maximum speed: 123 mph (107 kn, 198 km/h) at 5,000 ft (1,500 m)
- Range: 369 mi (320 nmi, 593 km)
- Service ceiling: 18,000 ft (5,500 m)
- Rate of climb: 889 ft/min (4.5 m/s)
- Bombs: 240 lb (110 kg)
- Related development
- Minus engine, instruments or guns
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- Shuttleworth Collection – Bristol F.2B Retrieved: 26 October 2010.
- Canada Aviation and Space Museum – Bristol F.2B Retrieved: 26 October 2010.
- Rare fighter plane to be shipped "home" to Bristol from US, BBC News, 9 September 2016
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- Cheesman, E. F. (ed). Fighter Aircraft of the 1914–1918 War. Letchworth, Harleyford, UK: Aero Publishers, Inc., 1960.
- Gutman, J. Bristol F2 Fighter Aces of World War 1. London: Osprey Publishing, 2007. ISBN 978-1-84603-201-1.
- Hare, Paul R. Fokker Fodder. United Kingdom: Fonthill, 2012. ISBN 978-1-78155-065-6.
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- Kopański, Tomasz Jan. Samoloty Brytyjskie w Lotnictwie Polskim 1918–1930 (British Aircraft in the Polish Air Force 1918–1930) (in Polish). Bellona, Warsaw: 2001. ISBN 83-11-09315-6.
- Wegg, John. General Dynamics Aircraft and their Predecessors. London: Putnam, 1990. ISBN 0-85177-833-X.
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