Bristol Type 118

Bristol Aeroplane Company

Industry	Aerospace, Defence
Founded	1910 (1910)
Founder	Sir George White (not in text but known founder, omit if strictly no inference allowed)
Headquarters	Filton , United Kingdom
Products	Aircraft

The Bristol Type 118 was a versatile two-seat military biplane developed by the Bristol Aeroplane Company in the early 1930s, powered by a Bristol Mercury radial engine and targeting international markets. Its variant, the Type 120, equipped with a Bristol Pegasus engine, was entered into an Air Ministry competition and subsequently employed for armament evaluation. Only two units were constructed.

Development

The Type 118 originated as a private initiative by Bristol, intended to serve multiple roles such as fighter, bomber, reconnaissance, and casualty evacuation for foreign air forces lacking resources to procure specialized aircraft. To accommodate these diverse missions, the design featured two seats and incorporated supercharging to achieve high-altitude performance necessary for tasks like photographic reconnaissance. Given the obsolescence of the Bristol Jupiter radial engine, the more modern Bristol Mercury was selected as the preferred powerplant. The initial prototype utilized a supercharged Bristol Jupiter XFA engine, while the second aircraft—designated Type 118A—was powered by a Mercury V.

Designed by Frank Barnwell, the aircraft was a streamlined single-bay biplane with staggered wings of unequal span. Wire bracing was limited to the centre section; beyond this, each wing featured a single streamlined compression strut and a three-strut drag brace. Only the upper wings carried Frise-type ailerons. The fuselage was constructed from metal covered with fabric, resembling that of the Bristol Bulldog. The rudder and elevators incorporated horn balances, while the cantilever tailplane remained unbraced. The undercarriage was divided, attached to the fuselage with streamlined legs and struts. Early Jaguar engines left cylinder heads exposed; later powerplants were enclosed within a Townend ring cowling.

The pilot’s cockpit was positioned high beneath a cutout in the upper wing’s trailing edge, equipped with a synchronized .303 in (7.7 mm) Vickers machine gun mounted on the port side in a trough. Situated behind was the observer’s cockpit, allowing roles such as rear gunner, bomb aimer, photographer or radio operator. For defensive purposes, a .303 in (7.7 mm) Lewis Gun was mounted on a Scarff ring for rearward firing. The observer could assume a prone position over floor windows for bombing or photography tasks, or alternatively accommodate one stretcher-bound occupant; a second casualty could be carried beneath removable rear fuselage decking. External bomb racks were also fitted.

The first prototype, powered by the Jaguar engine and registered as G-ABEZ, took to the air on 22 January 1931 with pilot Cyril Uwins. During 1931 it flew under experimental registration R-3 and obtained its airworthiness certificate by December that year. Plans for Baltic sales were hindered due to licensing disagreements over engine manufacture. Meanwhile, interest from the Air Ministry grew; they leased "R-3", now fitted with a Mercury V engine and four-blade propeller but without armament, to conduct endurance and desert trials in Iraq from February 1932. During these tests it bore RAF markings with serial K2873. After completion, it returned to Filton and remained in storage until April 1935 when it served as an engine test platform for the two-speed supercharged Bristol Pegasus XVII.

The second prototype initially designated Type 118A first flew on 29 January 1932 powered by its intended Mercury V engine and bearing experimental code R-6. By this time it had been re-designated Type 120 following installation of a rotatable turret or cupola over the gunner’s position. The Mercury V—recently renamed Pegasus—was replaced in April by a Pegasus I.M.3 engine. The cupola was a lightweight transparent enclosure that rotated with the Lewis gun mounted on an elevated Scarff ring inside the cockpit, offering protection from airflow especially beneficial when firing downward while standing.

File:B120.jpg

Bristol 120

In April, the Type 120 participated at Martlesham as an entrant for Air Ministry specification G.4/31 aimed at replacing older types like the Westland Wapiti and Fairey Gordon. It was ultimately unsuccessful largely because torpedo bombing had been added to required capabilities for general-purpose aircraft. Nonetheless, the Air Ministry acquired the Type 120 for drag testing of its turret by flying it both with and without this feature; during this period it bore RAF serial K3587. Continued licensing disputes prevented Spanish procurement interest from materialising.