History of Cubana de Aviación of its fleet, opting to replace its long-range piston-prop Super Constellations with turboprop aircraft, and to expand its existing Vickers Viscount turboprop fleet in the immediate future. Cubana placed orders for four long-range Bristol Britannia (Model 318) and four Vickers Super Viscount (VV-818) aircraft, all turboprops, for its international services (which included Madrid, New York, Mexico City, Miami, Montego Bay, Nassau, Port-au-Prince), and for some of its domestic routes (Camagüey, Santiago de Cuba, Varadero). The first Bristol Britannia (CU-T668) was delivered in late 1958, and was placed in service in the airline's New York route. The new Britannias and Super
Turboprop jet cruising speeds for most missions. The Bear would serve as their most successful long-range combat and surveillance aircraft and symbol of Soviet power projection throughout the end of the 20th century. The USA would incorporate contra-rotating turboprop engines, such as the ill-fated twin-turbine Allison T40 — essentially a twinned up pair of Allison T38 turboprop engines driving contra-rotating propellers — into a series of experimental aircraft during the 1950s, with aircraft powered with the T40, like the Convair R3Y Tradewind flying boat never entering U.S. Navy service. The first American turboprop engine was the General Electric XT31, first used