Bristol Bullfinch • wp.archivoaereo.com

In July 1920, Captain Frank Barnwell, with a group of engineers, began developing a new project for an all-metal parasol-wing fighter. It was envisioned that the aircraft would be produced in single-seater and two-seater variants. The Ministry of Aviation ordered the construction of three prototypes, which received the official designation Bristol Bullfinch in March 1922.

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Early Prototypes and Testing

By early 1923, the first two prototypes, in their single-seater variant, were completed. These aircraft featured wooden wings and a fuselage made of steel tubing. They were equipped with a 425-horsepower Bristol Jupiter III engine and armed with two synchronized 7.7mm Vickers machine guns. Throughout 1923, the aircraft underwent testing at the RAF research center. Despite good flight characteristics, a decision for serial production was not made.

The Two-Seater Bullfinch II and Project Cancellation

The third prototype of the aircraft, designated Bullfinch II, was completed in a two-seater variant. Its first flight took place on February 15, 1924. The aircraft received a second wing and a separate cockpit for the gunner, equipped with a 7.7mm Lewis machine gun on a movable Scarff turret. As a result, the aircraft’s flight weight increased by 400 kilograms (including the second pilot), leading to a noticeable reduction in flight performance—the 425 hp engine simply could not cope with the increased mass of the aircraft. This ultimately led to the project’s demise.

Technical Specifications

Modification	Bullfinch I
Wingspan, m	11.71
Length, m	7.44
Height, m	3.27
Wing area, m2	24.80
Empty weight	986
Normal takeoff weight	1454
Engine type	1 Piston engine Bristol Jupiter III
Power, hp	1 x 425
Maximum speed, km/h	217
Cruising speed, km/h	192
Flight endurance, h	4
Service ceiling, m	6096
Crew	1 crew member
Armament	two synchronized 7.7-mm Vickers machine guns