Bristol Type 146
Encyclopedia
The Bristol Type 146 was a British single-seat, eight-gun fighter
monoplane
prototype built to a mid-1930s Air Ministry
contract. Powered by a radial engine, it was outclassed by Merlin
-engined fighters and only one was built.
to an Air Ministry order for a prototype single-seat eight-gun fighter meeting Air Ministry specification F.5/34 issued in 1934. The specification further called for an air-cooled engine for overseas use. The Type 146 incorporated the experience of metal-skinned monoplanes that Bristol had gained with the earlier Type 133, but was quite different in detail.
The Type 146 embodied a low-wing cantilever monoplane with tapering wings that carried moderate dihedral on the outer sections. The wings were stress skinned with aluminium
with only the aileron
s and tail control surfaces fabric-covered. The two pairs of four 0.303 in (7.7 mm) Browning machine gun
s were housed in the outer wing sections. The undercarriage
was mounted about half way along the centre section and retracted cleanly inwards into the wing root; the tail wheel was also fully retractable. In contrast to the Type 133, the entire fuselage
was a monocoque
structure. The cockpit was enclosed with a one-piece sliding canopy.
The Type 146 was designed to be powered by a supercharged
Bristol Perseus
sleeve valve
d radial engine, but this was not ready and Bristol's older design the Bristol Mercury
IX radial was used instead.
at RAF Martlesham Heath
in April 1938. Its competitors there were the Gloster F.5/34
, the Martin-Baker MB2 and the Vickers Venom
.
Though the Type 146 met the specification neither it nor any of the other competing designs was taken into production. The RAF believed that the future of British fighter design was with the emerging Rolls-Royce Merlin
-engined aircraft (Specification F.36/34) which had more power and cleaner aerodynamics. The second Type 146 prototype was cancelled, while K5119 continued to fly.
On 28 May 1938, following an Empire Air Day
display at Filton Aerodrome
, the sole Type 146 while taxying, struck a "set-piece" display and was damaged beyond economic repair. It was the last single-engined fighter to be built by Bristol.
Fighter aircraft
A fighter aircraft is a military aircraft designed primarily for air-to-air combat with other aircraft, as opposed to a bomber, which is designed primarily to attack ground targets...
monoplane
Monoplane
A monoplane is a fixed-wing aircraft with one main set of wing surfaces, in contrast to a biplane or triplane. Since the late 1930s it has been the most common form for a fixed wing aircraft.-Types of monoplane:...
prototype built to a mid-1930s Air Ministry
Air Ministry
The Air Ministry was a department of the British Government with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964...
contract. Powered by a radial engine, it was outclassed by Merlin
Rolls-Royce Merlin
The Rolls-Royce Merlin is a British liquid-cooled, V-12, piston aero engine, of 27-litre capacity. Rolls-Royce Limited designed and built the engine which was initially known as the PV-12: the PV-12 became known as the Merlin following the company convention of naming its piston aero engines after...
-engined fighters and only one was built.
Design and development
The Bristol 146 was built by BristolBristol
Bristol is a city, unitary authority area and ceremonial county in South West England, with an estimated population of 433,100 for the unitary authority in 2009, and a surrounding Larger Urban Zone with an estimated 1,070,000 residents in 2007...
to an Air Ministry order for a prototype single-seat eight-gun fighter meeting Air Ministry specification F.5/34 issued in 1934. The specification further called for an air-cooled engine for overseas use. The Type 146 incorporated the experience of metal-skinned monoplanes that Bristol had gained with the earlier Type 133, but was quite different in detail.
The Type 146 embodied a low-wing cantilever monoplane with tapering wings that carried moderate dihedral on the outer sections. The wings were stress skinned with aluminium
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
with only the aileron
Aileron
Ailerons are hinged flight control surfaces attached to the trailing edge of the wing of a fixed-wing aircraft. The ailerons are used to control the aircraft in roll, which results in a change in heading due to the tilting of the lift vector...
s and tail control surfaces fabric-covered. The two pairs of four 0.303 in (7.7 mm) Browning machine gun
M1919 Browning machine gun
The M1919 Browning is a .30 caliber medium machine gun that was widely used during the 20th century. It was used as a light infantry, coaxial, mounted, aircraft, and anti-aircraft machine gun by the U.S. and many other countries, especially during World War II, the Korean War, and the Vietnam War...
s were housed in the outer wing sections. The undercarriage
Undercarriage
The undercarriage or landing gear in aviation, is the structure that supports an aircraft on the ground and allows it to taxi, takeoff and land...
was mounted about half way along the centre section and retracted cleanly inwards into the wing root; the tail wheel was also fully retractable. In contrast to the Type 133, the entire fuselage
Fuselage
The fuselage is an aircraft's main body section that holds crew and passengers or cargo. In single-engine aircraft it will usually contain an engine, although in some amphibious aircraft the single engine is mounted on a pylon attached to the fuselage which in turn is used as a floating hull...
was a monocoque
Monocoque
Monocoque is a construction technique that supports structural load by using an object's external skin, as opposed to using an internal frame or truss that is then covered with a non-load-bearing skin or coachwork...
structure. The cockpit was enclosed with a one-piece sliding canopy.
The Type 146 was designed to be powered by a supercharged
Supercharger
A supercharger is an air compressor used for forced induction of an internal combustion engine.The greater mass flow-rate provides more oxygen to support combustion than would be available in a naturally aspirated engine, which allows more fuel to be burned and more work to be done per cycle,...
Bristol Perseus
Bristol Perseus
|-See also:-Bibliography:* Bridgman, L, Jane's Fighting Aircraft of World War II. Crescent . ISBN 0-517-67964-7* Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9...
sleeve valve
Sleeve valve
The sleeve valve is a type of valve mechanism for piston engines, distinct from the usual poppet valve. Sleeve-valve engines saw use in a number of pre-World War II luxury cars and in USA in the Willys-Knight car and light truck...
d radial engine, but this was not ready and Bristol's older design the Bristol Mercury
Bristol Mercury
|-See also:-Bibliography:* Bridgman, L, Jane's fighting aircraft of World War II. Crescent. ISBN 0-517-67964-7* Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9...
IX radial was used instead.
Testing
The Type 146 flew for the first time on 11 February 1938 in the hands of Cyril Uwins and was flight tested satisfactorily before going on to be assessed against the F.5/34 specification by the Aeroplane and Armament Experimental EstablishmentAeroplane and Armament Experimental Establishment
The Aeroplane and Armament Experimental Establishment was a research facility for British military aviation from 1918 to 1992.-History:...
at RAF Martlesham Heath
RAF Martlesham Heath
RAF Martlesham Heath is a former Royal Air Force airfield in England. The field is located 1½ miles SW of Woodbridge, Suffolk.- RFC/RAF prewar use:Martlesham Heath was first used as a Royal Flying Corps airfield during World War I...
in April 1938. Its competitors there were the Gloster F.5/34
Gloster F.5/34
|-See also:-Bibliography:* Bowyer, Michael J.F. Interceptor Fighters for the Royal Air Force, 1935-45. Wellingborough, UK: Patrick Stephens Ltd., 1984. ISBN 0-85059-726-9....
, the Martin-Baker MB2 and the Vickers Venom
Vickers Venom
-References:NotesBibliography* Andrews, C.F. and E.B. Morgan. Vickers Aircraft since 1908, 2nd ed. London: Putnam, 1988. ISBN 0-85177-815-1. * Goulding, James. Interceptor. London: Ian Allen, 1986. ISBN 0-7110-1583-X....
.
Though the Type 146 met the specification neither it nor any of the other competing designs was taken into production. The RAF believed that the future of British fighter design was with the emerging Rolls-Royce Merlin
Rolls-Royce Merlin
The Rolls-Royce Merlin is a British liquid-cooled, V-12, piston aero engine, of 27-litre capacity. Rolls-Royce Limited designed and built the engine which was initially known as the PV-12: the PV-12 became known as the Merlin following the company convention of naming its piston aero engines after...
-engined aircraft (Specification F.36/34) which had more power and cleaner aerodynamics. The second Type 146 prototype was cancelled, while K5119 continued to fly.
On 28 May 1938, following an Empire Air Day
Commonwealth Day
Commonwealth Day is the annual celebration of the Commonwealth of Nations held on the second Monday in March, and marked by a multi-faith service in Westminster Abbey, normally attended by HM Elizabeth II, Head of the Commonwealth, with the Commonwealth Secretary-General and Commonwealth High...
display at Filton Aerodrome
Filton Aerodrome
Bristol Filton Airport or Filton Aerodrome lies on the border between Filton and Patchway, within South Gloucestershire, north of Bristol, England. The airfield is bounded by the A38 trunk road to the east, the former London to Avonmouth railway line to the south and the Old Filton Bypass road to...
, the sole Type 146 while taxying, struck a "set-piece" display and was damaged beyond economic repair. It was the last single-engined fighter to be built by Bristol.