In a stark contrast to the ‘big jet’ market, Europe came to dominate sales of first-generation turboprops, primarily through the efforts of Fokker, with its excellent F-27 Friendship.
The basic economics of the turboprop compared to the pure jet are as sound today as they were in the late 1940s. Arranging a turbine, or jet engine to drive a propeller through a gearbox produces a much more efficient source of motive power, especially over shorter ranges, but results in a considerably slower aircraft. There is always a delicate balance to be struck between fuel economy, range, speed and operating altitude.
The Brabazon Committee had recognized the advantages of the turboprop over the piston engine—higher aircraft speeds and much reduced vibration and noise – and recommended the production of such a machine under its Type IIB specification. The result was the Vickers Viscount which first flew on 16 July 1948. The type flew the world’s first turbine service on 29 July 1950 between London and Paris, but was too small for economical use. It was therefore redesigned to seat up to 69 passengers, in which form it conquered not only the European market, it also achieved sales in America. Indeed, the Viscount became one of Britain’s most successful airliners, with 438 sales.
BOAC had issued a specification for a larger medium-range airliner in 1947. Designed for its Empire routes, the Bristol machine was switched from piston to turboprop power before its first flight in 1952. It entered service as the Britannia, flying London-Johannesburg from February 1957 and London -New York from December, but it was soon overshadowed on the transatlantic routes by the Boeing 707.
Vickers also produced a larger turboprop, the four-engined Vanguard, for BEA. It proved only moderately successful, several of the 43 built were modified for continued service as Merchantman freighters.
Handley Page flirted briefly with the turboprop, producing the Herald as a rival to the Fokker F-27, having stuck doggedly to piston power long enough to lose any chance of competing. The company sold 48 Heralds, Fokker sold 582 F-27s
Hawker Siddely and, later, British Aerospace (BAe), had more success with the HS.748. Designed by Avro, the 748 entered service in 1962 and found favour with civilian and military customers. It enjoyed a new lease of life in the 1990s as the Advanced Turboprop (ATP).
FOKKERS AND FAIRCHILDS
Fokker became the undisputed champion of the first generation turboprop with its F-27 Friendship. First flown on 24 November 1955, the Friendship entered service with the United States’ West Coast Airlines on 28 September 1958 and in Europe with Aer Lingus in December. It sold well worldwide, but its penetration of the US market was greatly assisted by a licence-building arrangement with Fairchild, which built the type as the F-27. Later Fairchild became Fairchild Hiller, continuing with a stretched variant known as the FH-227. The F-27 also enjoyed a 1990s’ resurgence, as the basis of the evolved Fokker 50.
Lockheed attempted to enter the short/medium haul turboprop market with its L-188 Electra, which first flew in 1957. It offered high cruising speeds, excellent field performance and advanced powerplant and airframe but suffered a series of early accidents. The cause was ultimately identified and a fix developed but by that time the Boeing 727 was available and the Electra’s market had disappeared.
The Soviet Union produced its first long-range turbine aircraft just as it had produced its first jetliner, by installing an airliner fuselage between bomber wings. The Tu-114 added such a fuselage to the flying surfaces and powerplant of the Tu-195 bomber. The result was a phenomenal, if somewhat short lived unique turboprop airliner with swept wings.
Ilyushin’s IL–18 was more ambitious- a completely new, optimized design for efficient, modern, 75 seat passenger airliner. Entering service in 1959, 565 were built in several variants; production ceased in 1979.
Japan meanwhile, formed a consortium to design and build a first-generation turboprop, the YS-11. Capable and well built, it sold reasonably well in North America, Europe and Asia, but was always expensive in an already crowded market.
By courtesy of: Civil Aircraft 1907- Present by Paul E. Eden, Amber Books Ltd London 2012