Rolls-Royce Dart Rolls-Royce Dart The Rolls-Royce RB.53 Dart is a long-lived British turboprop engine designed, built and manufactured by Rolls-Royce Limited. First run in 1946, it powered the first Vickers Viscount maiden flight in 1948, and in the Viscount was the first turboprop engine to enter airline service, with British European Airways (BEA), in 1950. On 29 July 1948 a flight between Northolt and Paris–Le Bourget Airport with 14 paying passengers in a Dart-powered Viscount was the first scheduled airline flight by any turbine-powered aircraft. The Dart was still in production when the last Fokker F27 Friendships and Hawker Siddeley HS 748s
Turboprop Kaman's K-125 synchropter, which used a Boeing T50 turboshaft engine to power it on 11 December 1951. Compared to turbofans, turboprops are most efficient at flight speeds below 725 km/h (450 mph; 390 knots) because the jet velocity of the propeller (and exhaust) is relatively low. Modern turboprop airliners operate at nearly the same speed as small regional jet airliners but burn two-thirds of the fuel per passenger. However, compared to a turbojet (which can fly at high altitude for enhanced speed and fuel efficiency) a propeller aircraft has a lower ceiling. The most common application of turboprop engines in