It powered the Bristol Britannia airliner, small naval patrol craft, hovercraft and electrical generating sets.

Design work started in September 1944 with its free turbine and propeller gearbox based on the earlier Bristol Theseus engine.

The gas generator was built as a turbojet, and called the Bristol Phoebus, to speed development of the engine by not hindering it with gearbox problems.

It was test-flown in May 1946 fitted to the bomb bay of an Avro Lincoln, performance was poor and the first centrifugal compressor stage was removed.

A gearwheel stripped its teeth and the resulting damage set fire to the aircraft which made an emergency landing on the mud in the river Severn estuary.

BOAC started services in February 1957[5] but later in the year a third type of icing was encountered on flights to Australia.

The Italian Navy's hydrofoil Sparviero-class patrol boats used a Proteus to drive a pump jet at high speeds.

In this installation four "Marine Proteus" engines were clustered in the rear of the craft, exhausts pointed rearward.

At the pylons, gearboxes used the horizontal torque to power a vertical shaft, with a lift fan at the bottom and propeller at the top.

The two at the front required long shafts running above the passenger cabin, as all four engines were mounted at the rear of the craft.

[14][15] The regional electricity board installed several 2.7 MW remote operated generation sets for peak load powered by the Proteus.