Joseph Summers turboprop airliner (the Vickers Viscount) on 16 July 1948 and the initial flight of Britain's first four-jet bomber (Vickers Valiant) on 18 May 1951. By the time he retired, he had achieved 366 general types, second only to the Guinness world record holder Eric "Winkle" Brown who has 487. Summers still holds the world record of 54 "Prototype First Flights". On 15 December 2016, in a Boroondara Council meeting, Joseph Summers had the street formally known as Oliver Street renamed, to honour his work in the military. Summers married Dulcie Jeanette Belcher in 1922 in Sculcoates, Yorkshire. Summers died on
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