The Westland Interceptor was a
fighter developed by the
British
British may refer to:
Peoples, culture, and language
* British people, nationals or natives of the United Kingdom, British Overseas Territories, and Crown Dependencies.
** Britishness, the British identity and common culture
* British English, ...
company
Westland Aircraft
Westland Aircraft was a British aircraft manufacturer located in Yeovil, Somerset. Formed as a separate company by separation from Petters Limited just before the start of the Second World War, Westland had been building aircraft since 1915. D ...
to
Air Ministry Specification
This is a partial list of the British Air Ministry (AM) specifications for aircraft. A specification stemmed from an Operational Requirement, abbreviated "OR", describing what the aircraft would be used for. This in turn led to the specification ...
''F.20/27''.
When tested in 1929 and 1930, it showed unsatisfactory handling characteristics and was rejected by the RAF in favour of the
Hawker Fury
The Hawker Fury is a British biplane fighter aircraft used by the Royal Air Force in the 1930s. It was a fast, agile aircraft, and the first interceptor in RAF service capable of speed higher than 200 mph (321 kmh). It was the fighter co ...
biplane fighter.
Development
Specification F.20/27 was for a fighter operating in the daylight interception role. The main requirement was that the F.20/27 fighter would be able to overtake, in the shortest possible time, an enemy aircraft passing overhead at at an altitude of .
[Colin Sinnott, ''The Royal Air Force and Aircraft Design 1923-1939'', Frank Cass publishing, UK 2001.] This put the emphasis on high speed and rate of climb.
Design work on the Interceptor started in late 1927, and it made its first flight in early 1929, with Lieutnant L. G. Paget at the controls.
[James Goulding, ''Interceptor'', Ian Allan Ltd., UK 1986.] The Interceptor was a low-wing monoplane with an all-metal structure and wire-braced wings, covered mostly in fabric with the exception of the front fuselage. It had a fixed undercarriage. The single
prototype was powered by an uncowled
Bristol Mercury IIA
The Bristol Mercury is a British nine-cylinder, air-cooled, single-row, piston radial engine. Designed by Roy Fedden of the Bristol Aeroplane Company it was used to power both civil and military aircraft of the 1930s and 1940s. Developed from ...
, later replaced by a Mercury III. It was armed with two .303-inch (7.7-mm)
Vickers Mk.II machine guns, installed in the sides of the fuselage with the breeches within reach of the pilot. The guns were
synchronized to fire through the propeller, and heated to improve their operation at high altitude. The RAF had intended to call for four-gun armament in Specification F.20/27, but after an administrative mix-up it was sent out to manufacturers calling for only two guns.
The handling characteristics of the Interceptor have been described as "alarming."
[Tim Mason, ''British Flight Testing: Martlesham Heath 1920-1939'', Putnam, UK 1993] In steep turns the elevator became ineffective, and the aircraft was prone to enter a spiral dive or a
spin from such flight attitudes. The Mercury II engine suffered from persistent high oil temperatures. Test pilots gave a negative assessment of the Interceptor, causing it to be withdrawn from the F.20/27 competition.
The aircraft continued to fly until 1935, but no orders were placed. Significant aerodynamic modifications were made to improve the handling characteristics, including a considerable increase in the height of the fin and rudder, to improve spin recovery.
The troublesome Mercury engine was exchanged for a
Bristol Jupiter VII, and later fitted with a
Townend ring
A Townend ring is a narrow- chord cowling ring fitted around the cylinders of an aircraft radial engine to reduce drag and improve cooling.
Development
The Townend ring was the invention of Dr. Hubert Townend of the British National Physica ...
to reduce drag.
The Interceptor and two of the competing F.20/27 designs, the
Vickers Jockey and
de Havilland DH.77, were historically important because they were
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 planes.
A monoplane has inherently the highest efficiency and lowest drag of any wing con ...
fighter prototypes, after a long period during which the standard fighter design was a
biplane. However, all three were found lacking in overall performance and handling during the test flights, showing that the
aircraft designers
An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines. ...
had failed to reach the project goal.
The F.20/27 competition was won by the
Hornet
Hornets (insects in the genus ''Vespa'') are the largest of the eusocial wasps, and are similar in appearance to their close relatives yellowjackets. Some species can reach up to in length. They are distinguished from other vespine wasps by th ...
, which entered service under the name
Hawker Fury
The Hawker Fury is a British biplane fighter aircraft used by the Royal Air Force in the 1930s. It was a fast, agile aircraft, and the first interceptor in RAF service capable of speed higher than 200 mph (321 kmh). It was the fighter co ...
.
Specifications
See also
References
Derek N James: "Westland Aircraft Since 1915"
{{Westland aircraft
Interceptor
Interceptor may refer to:
Vehicles
* Interceptor aircraft (or simply "interceptor"), a type of point defense fighter aircraft designed specifically to intercept and destroy enemy aircraft
* Ford Crown Victoria Police Interceptor, a police car
* ...
1920s British fighter aircraft
Single-engined tractor aircraft
Low-wing aircraft
Aircraft first flown in 1929