Which Rolls-Royce engine was offered on the Boeing 707 and Vickers VC10?

The Rolls-Royce engine offered on both the Boeing 707 and Vickers VC10 was the Rolls-Royce Conway.

The Conway was one of the world’s first production turbofan engines. Rolls-Royce developed it during the 1950s, and its design used a bypass stream to improve fuel economy compared with a pure turbojet. The engine entered airline service in 1960 with BOAC’s Boeing 707-420s.

The Conway was also selected for the Vickers VC10, whose rear-mounted engines helped create a quiet, spacious passenger cabin. Different Conway variants powered aircraft including the Boeing 707, Boeing 720, Vickers VC10 and Handley Page Victor.

It is sometimes confused with the Rolls-Royce Spey, another important British turbofan used on later airliners and military aircraft. The Conway preceded the Spey and helped establish the commercial importance of turbofan propulsion.