During the 1920s, the British Royal Air Force (RAF) was in need of modernization and looked to succeed a fleet of aging combat aircraft with all-modern solutions. One requirement, drawn up as Specification F9/16, appeared in 1926 calling for a day / night fighter for "zone defense". Various designs were entered for consideration including several from aeroplane maker Armstrong Whitworth. One of their attempts became the "AW.16".
The AW.16 continued the tried-and-true construction methods and aircraft arrangement used since The Great War (1914-1918). It was a single-seat, single-engine type with biplane wing configuration and sat its pilot in an open-air cockpit. The undercarriage, fixed during flight, relied on a wheeled, twin-leg (under center mass) and tailskid configuration for ground-running. The engine was set in the nose in the usual way and was used to drive a two-bladed propeller unit in tractor fashion.
The wing mainplane members were of unequal span (the upper member being wider than the lower) and "N-style" struts were used. A single bay was formed between the fuselage and the N-strut works while bracing was also reinforced by cabling. The wings were positioned ahead of midships with the upper member moved noticeably ahead of the lower (known as "staggered"). This, of course, reduced pilot visibility out-of-the-cockpit at the forward and down views - his placement was close to midships which set him well-aft of the nose.
The undercarriage was strutted by way of thick supports and the wheels partially faired over for inherent aerodynamic efficiency at these components. The tail unit was conventional with a single vertical fin (rounded in its general shape)in play and fuselage-mounted horizontal tailplanes. All told, the aircraft was very traditional and borrowed much from Armstrong Whitworth's earlier work on the similar "Starling" biplane fighter design (detailed elsewhere on this site).
Power to the fighter was from the in-house Armstrong Siddeley "Panther" series air-cooled, radial piston engine for the two-bladed propeller. The powerplant was shrouded over in a "Townend" ring, a slim cowling assembly fitted up against the row of cylinders providing enhanced cooling as well as aerodynamic efficiency.
Armament was typical for the time: 2 x 0.303 caliber (7.7mm) Vickers Machine Guns in fixed, forward-firing installations synchronized to fire through the spinning propeller blades. 500 rounds were afforded per gun giving the weapons an ample supply of ammunition for extended fighting.
In prototype form, the AW.16 went to the air for the first time in 1930, some years after the original RAF requirement originated. As a result, the company suggested its fighter for Specification N21/26 which saw the Royal Navy's Fleet Air Arm seeking a navy-minded "fleet fighter". Even then, the aircraft fared poorly against the competition due to engine troubles and handling issues - to which point the competing Hawker "Nimrod" (detailed elsewhere on this site) was already in line to succeed. In testing under ideal conditions, the AW.16 managed a maximum speed of 200 miles-per-hour, a range out to 270 miles, and a service ceiling near 26,000 feet.
As completed, the aircraft had a running length of 25 feet, a wingspan of 33 feet, and a height of 11.5 feet. Empty weight was 2,800lb with a Maximum Take-Off Weight (MTOW) of 3,520lb being possible.
Despite these setbacks, the aircraft's development continued and Armstrong Whitworth turned to the export market to recoup some of the expense of bringing this fighter to light. By this time, a second prototype was constructed and this form switched to the "Panther IIA" series engine in an attempt to rectify earlier issues with performance and reliability. This version was offered against RAF Specification F7/30 of 1930 but the aircraft was more or less obsolete by Western standards and not under serious consideration (the contract was eventually won by the Gloster "Gladiator" detailed elsewhere on this site).
In 1933, Armstrong Whitworth re-engined their first AW.16 prototype to take on the powerful Armstrong Whitworth "Hyena" engine of 15-cylinders but cooling remained an issue and the project was discarded. Similarly, the second prototype was reworked to become the "Scimitar" but only six were produced and operated by Norway.
The only claim-to-fame the AW.16 actually earned was its service to the Kwangsi Air Force of China. At least sixteen of the type were taken on with the stock produced during 1931. In 1937, this fleet was brought under the banner of the Chinese Nationalist Air Force for service in World War 2 (1939-1945).