A seeming throwback to an earlier era, the Vickers 161 nevertheless packed a heavy punch.
There have been many instances in which warplanes were specifically designed around the armament they carried. Few examples have been as extreme or bizarre in appearance, however, as the Vickers Type 161. What makes the aircraft even stranger is that it looks like a fighter developed around 1915, but the Vickers 161 was actually built in 1930, when its archaic pusher configuration was generally considered long obsolete.
Vickers developed the 161 to satisfy a British Air Ministry request for a single-seat bomber interceptor, and the weapon around which it was designed was Coventry Ordnance Works’ 1½-pounder quick-firing gun. Developed in 1915, COW’s 1½-pounder was a recoil-operated 37mm automatic cannon, nearly eight feet long and weighing 200 pounds. On one occasion when a COW gun was test-fired from a Voisin pusher in 1915, the recoil reportedly tore the wings off the fuselage, killing the occupants in the ensuing crash. But by the time World War I ended, further developments in both weaponry and aircraft had reached a stage where a few examples were being successfully installed on operational airplanes.
As a result of the post-WWI economic downturn, in 1925 Vickers took over Coventry Ordnance Works and its patents. Nevertheless, the Air Ministry remained interested in the COW gun. During the 1920s, COW 1½-pounders were installed experimentally in the forward gunners’ cockpits of a few of the larger flying boats for use against submarines or small surface vessels. In addition, Bristol was contracted to develop a twin-engine, three-seat heavy fighter in 1924 that was to be armed with two of the 1½-pounders. The resulting aircraft, dubbed the Bristol Bagshot, proved to be underpowered and was soon abandoned.
In 1927 the Air Ministry issued a new specification, F.29/27, for a single-engine, single-seat COW gun–armed bomber destroyer. The gun was to be mounted to fire forward and upward at a 45-degree angle. The idea was that the fighter would attack enemy bombers from below and behind.
Both Westland and Vickers produced prototypes with the COW gun obliquely firing forward and upward, and positioned so the pilot could reach it to reload or clear jams. The Westland prototype was a conventional and, for the time, modern-looking low-wing tractor monoplane. Vickers’ solution was quite the antithesis: a pusher biplane in which the pilot was seated in a nacelle attached to the bottom of the upper wing. A Bristol Jupiter radial engine, mounted at the rear of the nacelle, drove a four-blade propeller. The tail was attached to the aircraft by means of a latticework of streamlined struts. A long, cone-shaped fairing extended from the propeller hub to the tailplane, supposedly enhancing directional stability.
That Vickers elected to use such an archaic configuration may seem less surprising when one considers that the company developed a whole series of pushers during WWI, and persisted with the configuration far longer than most other manufacturers of that period. In 1912 Vickers had built the first airplane specifically designed to carry a machine gun, the experimental Vickers EFB-1 Destroyer. That prototype evolved into the F.B.5 Gunbus, which may have been the first purpose-built air combat fighter to enter series production. As late as May 1917, when most other manufacturers had abandoned that configuration, Vickers flew its F.B.26 Vampire, a single-seat pusher fighter that shared similarities with the 161.
In spite of its anachronistic appearance, the 161 included many modern features. Apart from fabric covering on the wings and tail surfaces, the entire airframe was constructed from lightweight aluminum alloy, and the nacelle was of monocoque structure. The state-of-the-art Bristol Jupiter VIIF air-cooled radial engine produced 530 hp.
First flown on January 21, 1931, the Vickers 161 seems to have performed fairly well apart from a minor degree of directional instability, remedied by installing a slightly larger-chord fin and rudder. During September of that same year, the 161 was delivered to the Armament and Aircraft Experimental Establishment at Martlesham Heath for official evaluation. By that time, however, the Royal Air Force had begun to lose interest in the COW gun, and further development was soon abandoned. Considering that RAF fighter pilots of the day had the choice of flying either the Vickers 161 or the more advanced Hawker Fury, that’s not surprising. Moreover, the COW gun’s 50 rounds of ammunition came loaded in five-round clips, which the pilot had to reload by hand while flying the airplane.
The sole Vickers 161 built was 23 feet 6 inches long, with a 32-foot wingspan and a gross weight of 3,350 pounds. Its top speed was recorded as either 185 mph or 169 mph; given the aircraft’s outdated configuration, the latter figure seems more reasonable.
Although the RAF eventually rejected the 1½-pounder COW gun and the specialized fighters designed to carry it, Vickers would go on to develop an updated version, the Vickers S Gun, chambered for its own 40mm ammunition. Armed with a single S Gun beneath each wing, the Hawker Hurricane became a very effective anti-tank and ground-attack aircraft, and was widely used in North Africa and Burma during World War II.
This feature originally appeared in the May 2018 issue of Aviation History. Subscribe today!