The Bristol 76 Jupiter Fighter was a conversion of the Bristol Fighter for the purposes of demonstrating the Jupiter engine to potential customers.
Three conversions were made; the first (G-EBGF) flying early in June 1923 and being displayed at the July Göteborg Aero Show.
Other than the Jupiter engine and introduction of an oleo undercarriage, there was little change to the standard Bristol Fighter airframe.
There was two additional conversions (G-EBHG and G-EBHH).
The Jupiter Fighter proved to be fast, with a maximum speed of 134 mph but it was short in its range as the fuel capacity had not been increased to reflect the extra power (and fuel consumption) of the Jupiter engine.
During trials at Torslanda, associated with the Göteborg event, the first aircraft (G-EBGF) won the altitude prize and as well as an aerobatic competition for two-seat aircraft.
The Swedish government purchased one of the converted aircraft (G-EBHG) with which it conducted Arctic trials at Kiruna during 1924, operating on skis.
During its career with the Swedish Air Force, this aircraft also operated with serial numbers 4300, 1300 and 3667. In 1935 however, it was sold to Hugo Frederikson as 'surplus to requirements', receiving the civil a Swedish registration (SE-AEE) until it was destroyed in an accident at Göteborg in 1936.
The first aircraft (G-EBGF) was comparatively short-lived, having suffered a landing accident on 23rd November 1923, following an engine failure at 20,000ft.
The third aircraft (G-EBHH) was used experimentally for dual fuel testing. It was fitted with a high compression engine and flew with separate fuel tanks, one carrying petrol and and the other alcohol.
The intention was to take off using the alcohol fuel system and switch over to petrol at an altitude where detonation would not occur. The system also required two separate fuel systems, each with its own carburettor, but it offered higher performance figures at altitude.
In the event, problems were encountered with tank corrosion in the alcohol fuel system and ultimately engine supercharging became the preferred solution to maintaining performance at altitude.
The Jupiter-powered Advanced Trainer (Bristol Type 89) was developed from the Jupiter Fighter and is described separately. One aircraft (G-EBHH) was later converted to an Advanced Trainer and used by the Filton Reserve Flying School.
|Powerplant||One 425 hp Bristol Jupiter IV|
|Span||39 ft 3 in|
|Maximum Weight||3,080 lb|
|Capacity & Armament||Pilot and gunner|
|Maximum Speed||134 mph|
Three aircraft only, G-EBGF. G-EBHG, G-EBHH.