Which Rolls-Royce turboprop engine powered the Vickers Viscount?

The Rolls-Royce turboprop engine that powered the Vickers Viscount was the Rolls-Royce Dart.

The Dart was one of the earliest successful commercial turboprop engines. It powered the Vickers Viscount, which became the first turboprop airliner to enter regular passenger service when British European Airways introduced it in 1950.

The engine’s name followed Rolls-Royce’s convention of using names associated with rivers. Its compact design and relatively smooth operation helped make the Viscount popular with airlines serving short- and medium-haul routes. More than 400 Viscounts were built, making the type one of the most influential early turboprop airliners.

The Dart is often confused with the larger Rolls-Royce Tyne, which powered aircraft such as the Transall C-160 and Canadair CL-44. The Proteus was another turboprop, but it was associated particularly with the Bristol Britannia rather than the Viscount.