The Bristol Type 123 was a single-seat, single-engine

biplane A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...

fighter built to a United Kingdom

Air Ministry The Air Ministry was a department of the Government of the United Kingdom with the responsibility of managing the affairs of the Royal Air Force and civil aviation that existed from 1918 to 1964. It was under the political authority of the ...

specification for a four-gun fighter in the early 1930s. Only one was built.

Development

In late 1931 the

released Air Ministry specification F.7/30. This was for a four-gun fighter with better high-altitude performance and endurance than current fighters, outstanding climb rate, manoeuvrability and all-round vision combined with a low landing speed. It was made clear that the evaporatively-cooled

Rolls-Royce Goshawk The Rolls-Royce Goshawk was a development of the Rolls-Royce Kestrel that used evaporative or steam cooling. In line with Rolls-Royce convention of naming piston engines after birds of prey, it was named after the goshawk. The engine first ...

was the preferred engine. The best-known outcome of this specification was the crank-winged

Supermarine Type 224 The Supermarine Type 224 was a British gull-wing monoplane fighter aircraft designed by R.J. Mitchell at Supermarine in response to Air Ministry Specification F.7/30, which sought to introduce a new fighter to succeed the Gloster Gauntlet. T ...

monoplane A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple wings. A monoplane has inherently the highest efficiency and lowest drag of any wing con ...

with an open cockpit and fixed

undercarriage Undercarriage is the part of a moving vehicle that is underneath the main body of the vehicle. The term originally applied to this part of a horse-drawn carriage, and usage has since broadened to include: *The landing gear of an aircraft. *The ch ...

designed by R.J. Mitchell. Bristol submitted several biplane designs, none of which brought an order for a prototype, but they were invited to offer a private-venture aircraft. The Bristol Type 123 was the result. Bristol's last biplane, it was of compact, striking appearance and had innovative control features. It was a single-bay biplane with wings of constant chord almost to the tips and heavy stagger. The upper wings were swept and without dihedral, the

cantilever A cantilever is a rigid structural element that extends horizontally and is unsupported at one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a cantilev ...

lower wings unswept with 6° of dihedral. Both wings carried full-span

aileron An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement aroun ...

s. The upper wing also carried full-span slots on the leading edge, arranged in inner and outer groups. The ailerons were linked to

interceptors An interceptor aircraft, or simply interceptor, is a type of fighter aircraft designed specifically for the defensive interception role against an attacking enemy aircraft, particularly bombers and reconnaissance aircraft. Aircraft that are cap ...

behind the outer slots which rose when the inner slots opened at high angles of attack. As this happened, the ailerons drooped symmetrically. The slot-plus-interceptor combination was intended to prevent a stall turning into a spin and had been tested by

Handley Page Handley Page Limited was a British aerospace manufacturer. Founded by Frederick Handley Page (later Sir Frederick) in 1909, it was the United Kingdom's first publicly traded aircraft manufacturing company. It went into voluntary liquidation a ...

on a

de Havilland Moth The de Havilland Moths were a series of light aircraft, sports planes, and military trainers designed by Geoffrey de Havilland. In the late 1920s and 1930s, they were the most common civilian aircraft flying in Britain, and during that time eve ...

and later by Bristol on a

Bulldog The Bulldog is a British breed of dog of mastiff type. It may also be known as the English Bulldog or British Bulldog. It is a stocky, muscular dog of medium size, with a large head, thick folds of skin around the face and shoulders and a rel ...

Rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, airship, or other vehicle that moves through a fluid medium (usually air or water). On an airplane, the rudder is used primarily to counter adverse yaw ...

and

elevator An elevator (American English) or lift (Commonwealth English) is a machine that vertically transports people or freight between levels. They are typically powered by electric motors that drive traction cables and counterweight systems suc ...

s were horn balanced, the latter carrying

trim tab Trim tabs are small surfaces connected to the trailing edge of a larger Flight control surfaces, control surface on a boat or aircraft, used to control the trim of the controls, i.e. to counteract hydro- or aerodynamic forces and stabilise the ...

s. The wings,

empennage The empennage ( or ), also known as the tail or tail assembly, is a structure at the rear of an aircraft that provides stability during flight, in a way similar to the feathers on an arrow.Crane, Dale: ''Dictionary of Aeronautical Terms, third ed ...

and

fuselage The fuselage (; from the French language, French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds Aircrew, crew, passengers, or cargo. In single-engine aircraft, it will usually contain an Aircraft engine, engine as wel ...

behind the cockpit were all fabric covered over a metal structure. The combination of heavy stagger and a slender nose gave the Type 123 a slightly humpbacked appearance, with the pilot's open cockpit at the top above the centre of the lower wing and well behind the trailing edge of the upper wing. There were pairs of machine guns on either side of the engine. The

was fixed and almost completely enclosed in forward-thrusting fairings with a cross-axle between the wheels. The aircraft was powered by a Goshawk III loaned by the

, which used condensers in the lower wing leading edge for cooling, coupled to a forward-mounted ventral condenser. Engine cooling problems delayed the first flight, made by

Cyril Uwins Cyril Frank Uwins OBE, AFC, FRAeS (1896–1972) was a British test pilot who worked for Bristol Aeroplane Company, where he made the first flight of 58 types of aircraft. On 16 September 1932 he broke the world aeroplane height record by climbin ...

on 12 June 1934. Testing revealed serious lateral instability that a series of modifications to fin, rudder and the inner slots failed to cure, and which may have been structural. Development was therefore abandoned.

Specifications

References

Notes

Bibliography

* * * * {{Bristol aircraft 1930s British fighter aircraft Type 123 Cancelled military aircraft projects of the United Kingdom Single-engined tractor aircraft Biplanes