Developed from the earlier Mercury and Jupiter engines, later variants could produce 1,000 horsepower (750 kilowatts) from its capacity of 1,750 cubic inches (28 L) by use of a geared supercharger.

Although having a capacity (25 L) almost 15% smaller, the Mercury produced about as much power as the Jupiter, through a combination of supercharging to improve the "charge", and various changes to increase the operating RPM.

[1] The Pegasus was the same size, displacement and general steel/aluminium construction as the Jupiter, but various improvements allowed the maximum engine speed to be increased from 1,950 to 2,600 rpm for take-off power.

It was also used on the Anbo 41, Bristol Bombay, Saro London, Short Empire, Vickers Wellesley and the Westland Wallace.

It was used for the first flight over Mount Everest in the Westland Wallace, and in 1938 set the world's long-distance record in Vickers Wellesleys.

[5] The Pegasus was produced in many variants, early prototype engines were unsupercharged but the majority used a geared supercharger, either single-speed or two-speed.

An unrestored Pegasus recovered from the sea bed is in the care of the Bristol Aero Collection, which is closed while moving from Kemble Airport to Filton.