The little known Hawker Hoopoe was a Prototype Naval Fighter designed and built in 1927 as a private venture project.
Air Ministry Specification N.21/26 was issued in 1926 as a result of developments and improvements in the operating techniques of naval fighters, and the Air Staff started looking for a single-seat deck-landing fighter of modern construction and performance. The Specification demanded an all-metal structure and the fitting of a 450 hp Bristol Mercury nine-cylinder air-cooled radial engine, then still a relatively new powerplant.
Initially started in the first half of 1927, the Hoopoe biplane (named after the Afro-Eurasian bird) sported two-bay wings and an uncowled Bristol Mercury II engine. The type was submitted for consideration as a candidate to fulfil N.21/26 after the prototype (Royal Navy serial N237) had made its first flight in October 1928.
In early 1929, the Hoopoe was sent to the Aeroplane & Armament Experimental Establishment (A & AEE) at Martlesham Heath, where its performance impressed the unit’s pilots.
However, on its return to Hawker from the A & AEE, the Hoopoe was fitted with twin floats and sent to the Marine Aeroplane Experimental Establishment at Felixstowe where its performance with the ungainly floats revealing that the aircraft was in fact significantly underpowered. Accordingly an uprated 520 hp Mercury VI engine was fitted and the floats were replaced with the original wheeled undercarriage.
After another stint at the A & AEE in 1929, the Hoopoe was again returned to the Hawker factory at Kingston to be fitted with a 400 hp Armstrong Siddeley Jaguar 14-cylinder radial engine with a Townend ring, and significantly, single-bay wings. These modifications improved the aircraft’s performance to some degree, although the Hoopoe was still found wanting in terms of horsepower.
To that end, the Hoopoe was fitted in early 1930 with a 560 hp Armstrong Siddeley Panther III radial engine with two concentric Townend rings of unequal diameter. Aerodynamic wheel fairings or 'spats' were also added and the airframe 'cleaned up'.
The Panther was a better match for the Hoopoe and was uprated yet again to provide the fighter with an excellent top speed with pilots at the A & AEE squeezing nearly 200 mph out of the machine during trials at Martlesham Heath - an extremely impressive performance for a heavily-equipped radial-engine naval fighter.
In July 1932, the sole Hoopoe was sent for Service Trials with No 402 Flight and over the following few months completed deck-landing trials aboard HMS Courageous.
By this time, however, another Hawker product (the Norn which was later to become the Nimrod) was showing a great deal of promise with the Rolls-Royce Kestrel engine.
Thereafter, no further development of the Hoopoe took place.
After use by Armstrong Siddeley and the Royal Aircraft Establishment, the Hoopoe was withdrawn from flying in September 1932 and was scrapped later the same year.
Variants & Numbers
One aircraft onle, N237, flown in different configurations and different engines.
|Powerplant||One 450 hp Bristol Mercury II nine-cylinder air-cooled radial engine. Later one 520 hp Bristol Mercury VI; one 400 hp Armstrong Siddeley Jaguar 14-cylinder air-cooled radial engine; one 560 hp Armstrong Siddeley Panther III 14-cylinder air-cooled radial engine|
|Span||Two-bay wings: 34ft 6in; Single-bay wings: 33ft 2in|
|Maximum weight||Mercury II engine: 3,550lb; Jaguar engine: 3,600lb; Panther engine: 3,910lb|
|Capacity and Armament||Single pilot; Two fixed forward-firing Vickers machine-guns with 530 rounds each; provision for four 20lb bombs on underwing racks|
|Maximum speed||196·5 mph at 12,500ft|
The sole Hawker Hoopoe was scrapped in 1932.