– the world's first working turboprop-powered aircraft.
Alan Arnold Griffith had published a paper on compressor design in 1926.
Subsequent work at the Royal Aircraft Establishment investigated axial compressor-based designs that would drive a propeller. From 1929,
Frank Whittle began work on centrifugal compressor-based designs that would use all the gas power produced by the engine for jet thrust. The world's first turboprop was designed by the
Hungarian mechanical engineer György Jendrassik. Jendrassik published a turboprop idea in 1928, and on 12 March 1929 he patented his invention. In 1938, he built a small-scale (100 Hp; 74.6 kW) experimental gas turbine. The larger
Jendrassik Cs-1, with a predicted output of 1,000 bhp, was produced and tested at the
Ganz Works in
Budapest between 1937 and 1941. It was of axial-flow design with 15 compressor and 7 turbine stages, annular combustion chamber. First run in 1940, combustion problems limited its output to 400 bhp. Two Jendrassik Cs-1s were the engines for the world's first turboprop aircraft – the
Varga RMI-1 X/H. This was a
Hungarian fighter-bomber of
WWII which had one model completed, but before its first flight it was destroyed in a bombing raid. In 1941, the engine was abandoned due to war, and the factory converted to conventional engine production. , in March 1945 The first mention of turboprop engines in the general public press was in the February 1944 issue of the British aviation publication
Flight, which included a detailed cutaway drawing of what a possible future turboprop engine could look like. The drawing was very close to what the future Rolls-Royce Trent would look like. The first British turboprop engine was the
Rolls-Royce RB.50 Trent, a converted
Derwent II fitted with reduction gear and a
Rotol five-bladed propeller. Two Trents were fitted to
Gloster Meteor EE227 — the sole "Trent-Meteor" — which thus became the world's first turboprop-powered aircraft to fly, albeit as a test-bed not intended for production. It first flew on 20 September 1945. From their experience with the Trent, Rolls-Royce developed the
Rolls-Royce Clyde, the first turboprop engine to receive a
type certificate for military and civil use, and the
Dart, which became one of the most reliable turboprop engines ever built. Dart production continued for more than fifty years. The Dart-powered
Vickers Viscount was the first turboprop aircraft of any kind to go into production and sold in large numbers. It was also the first four-engined turboprop. Its first flight was on 16 July 1948. The world's first single engined turboprop aircraft was the
Armstrong Siddeley Mamba-powered
Boulton Paul Balliol, which first flew on 24 March 1948. is the most powerful turboprop to enter service The Soviet Union built on German World War II turboprop preliminary design work by Junkers Motorenwerke, while BMW,
Heinkel-Hirth and
Daimler-Benz also worked on projected designs. While the Soviet Union had the technology to create the airframe for a jet-powered strategic bomber comparable to Boeing's
B-52 Stratofortress, they instead produced the
Tupolev Tu-95 Bear, powered with four
Kuznetsov NK-12 turboprops, mated to eight
contra-rotating propellers (two per nacelle) with supersonic tip speeds to achieve maximum cruise speeds in excess of 575 mph, faster than many of the first
jet aircraft and comparable to 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 through to the end of the 20th century. The USA used turboprop engines with contra-rotating propellers, such as the
Allison T40, on some experimental aircraft during the 1950s. The T40-powered
Convair R3Y Tradewind flying-boat was operated by the U.S. Navy for a short time. The first American turboprop engine was the
General Electric XT31, first used in the experimental
Consolidated Vultee XP-81. The XP-81 first flew in December 1945, the first aircraft to use a combination of turboprop and
turbojet power. The technology of Allison's earlier T38 design evolved into the
Allison T56, used to power the
Lockheed Electra airliner, its military maritime patrol derivative the
P-3 Orion, and the
C-130 Hercules military transport aircraft. The first turbine-powered, shaft-driven helicopter was the
Kaman K-225, a development of
Charles Kaman's K-125
synchropter, which used a
Boeing T50 turboshaft engine to power it on 11 December 1951. December 1963 saw the first delivery of
Pratt & Whitney Canada's PT6 turboprop engine for the then Beechcraft 87, soon to become
Beechcraft King Air. 1964 saw the first deliveries of the
Garrett AiResearch TPE331, (now owned by
Honeywell Aerospace) on the
Mitsubishi MU-2, making it the fastest turboprop aircraft for that year. ==Usage==