The Theseus was the Bristol Aeroplane Company's first attempt at a gas-turbine engine design. A turboprop delivering just over 2,000 hp (1,500 kW) was chosen rather than compete with companies that were already developing turbojets. A heat exchanger to transfer waste heat from the exhaust to the compressor exit was necessary to meet a requirement for a fuel consumption comparable to a piston engine. However, the heat exchanger was abandoned after tests showed that it had a high pressure loss and only produced a fuel saving of 8%. Furthermore overall performance was reduced As well as being one of the first engines to feature a free propeller turbine, the Theseus was the first turboprop in the world to pass a type test in January 1947. Following 156 hours of ground runs and the receipt of a test certificate from the Ministry of Supply on 28 January 1947, two Theseus engines were fitted in the outer positions of a four-engined Avro Lincoln for air tests. After ground and taxying test the Lincoln first flew on 17 February 1947. The engine was also installed in two Handley Page Hermes 5 development aircraft. It was soon superseded by the Proteus design with more power.

Applications

Bristol Theseus on public display

East Midlands Aeropark Castle Donington.

Variants

Specifications (Theseus Th.21)