Armstrong Whitworth AW.16
The Specification 21/26, issued by the Air Ministry's Directorate of Technical. Development (DTD) on September 30, 1926, called for a "Single Seater Fighter Ship-plane for use from HM ships," fitted with a land undercarriage which could be replaced by floats, and vice versa, within half an hour. The aircraft, which was to have an all-metal structure but could be fabric covered, was to be suitable for launch from a catapult and for taking-off from and alighting on the deck of an aircraft carrier.
Engines specified were the air-cooled Bristol Mercury radial giving 550hp at 2,000rpm or the water-cooled Rolls-Royce Falcon X giving 480hp at 2,300rpm. A metal propeller was specified.
There was to be tankage for 74 gallons of fuel, plus an easily removed 20 gallon auxiliary tank and a gravity tank of sufficient capacity to allow half an hour's flight at full power at ground level. An 11 gallon oil tank was to be provided if the Mercury engine was used, or an 8.5 gallon oil tank and a 2.5 gallon reserve water tank for the Falcon.
Alternative exhaust systems for day or night flying were required, and were to be easily changed.
Additional equipment to be carried during the acceptance flights weighed 5581b and included a Vickers 0.5in gun and 300 rounds, a Vickers 0.303in gun and 600 rounds, a rocket launching (R/L) tube and six bombs, and flotation gear. A second 0.303in gun with 600 rounds was to be provided for if the 0.5in gun was not available in time.
Minimum performance requirements with this load, using the Mercury, called for a horizontal speed of 132kt (152mph) at 10,000ft and a service ceiling of 23,000ft. With the Falcon X the figures were 127kt (146mph) at 10,000ft and 22,000ft. The length of run to take-off was not to exceed 47ft in a relative wind of 28kt (32mph), and the aircraft was to become airborne at a speed of 55mph when catapulted in still air. The suitability for launching from a catapult or alighting on the deck of an aircraft carrier was "of first importance", and the aircraft had to be capable of taking-off from a turret or cruiser platform.
Despite the emphasis placed on the machine's naval use, it was stressed that: "The aircraft is to be designed primarily as a landplane fighter and qualities required for this work are not to be sacrificed in order to improve its characteristics when equipped with the float alighting gear".
A limit of 35ft was put on the wing span, the overall length was restricted to 23ft, the height was not to exceed 14ft 9in. Quick and easy removal and erection of the wings was specified, with the ability to remove the wing structure completely in ten minutes and replace it in fifteen minutes.
Tendering for this demanding specification were Armstrong Whitworth, which offered the AW XVI; Fairey, with the Flycatcher II; Gloster, which tendered the Gnatsnapper; Hawker, which offered the Hoopoe; Vickers, with a modified version of its Type 141 Scout; and George Pamall & Co.
Developed as a private venture to meet the requirements of both N.21/26 and F.9/26, the A.W.16 appeared in 1931. Two prototypes were flown. The first conforming to N.21/26 and the second to F.9/26, both being initially powered by the geared and supercharged Panther IIIA of 540hp. The second prototype was re-engined with a 565hp Panther VII during the course of trials at the A & AEE in 1933. Eighteen production examples of the A.W.16 were produced late in 1931, 17 of these for delivery to the Chinese Kwangsi Air Force and one being used as an engine test bed before being passed to the Alan Cobham circus. Armament comprised two 7.7mm Vickers machine guns.
Engine: Panther IIIA, 540hp
Take-off weight: 1597 kg / 3521 lb
Wingspan: 10.06 m / 33 ft 0 in
Length: 7.62 m / 25 ft 0 in
Height: 3.50 m / 11 ft 6 in
Wing area: 24.24 sq.m / 260.92 sq ft
Max. speed: 322 km/h / 200 mph