Aviation
Art by David Gibbings
Retired Westland
Flight Test Engineer
Drawings
originally produced for “The Helicopter” by John Fay, ISBN 0-7153-8940-8
(1979).
Paul Cornu’s helicopter was long believed to have been the first successful helicopter to achieve controlled hover flight in November 1907. Recent research, however, published by AHS, indicate that it did not achieve free flight.
Louis Charles Bréguet (of the Breguet Range Equation fame), with assistance from his brother and Professor Charles Richet, built what is considered to be the first vertical flight machine to rise off the ground in September 1907, steadied by four men steadying the structure. Jean Boulet’s groundbreaking book, “History of the Helicopter – As Told by Its Pioneers, 1907-1956,” notes that the supporters were holding it up, not down.
Étienne Œhmichen was a French engineer and designer. His first successful flight with a helicopter – augmented by a balloon – took place on February 18, 1921. On November 11, 1922, he first flew the ‘Œhmichen No.2', an improved helicopter featuring small vertically mounted rotors which rotated in the opposite direction from the large lifting rotors, creating probably the first reliable flying helicopter capable of carrying a person. On April 14, 1923, he broke the existing record for helicopter flight with a flight of 358 m (1,175 ft). On May 4, 1924 he won a prize of 90,000 French Francs for the first successful closed circuit helicopter flight with a length of one km (3,280 ft).
In the early 1920s, Argentine Raúl Pateras-Pescara de Castelluccio, while working in Europe, demonstrated one of the first successful applications of cyclic pitch. Coaxial, contra-rotating, biplane rotors could be warped to cyclically increase and decrease the lift they produced. On April 18 1924, Pescara beat Œhmichen’s first record, flying for a distance of 736 meters (2,414 ft).
In 1928, Hungarian aviation engineer Oszkár Asbóth constructed a helicopter prototype that took off and landed at least 182 times, with a maximum single flight duration of 53 minutes.
Louis Bréguet and Rene Dorand established the Gyroplane company in 1931 and completed their Bréguet-Dorand Gyroplane Laboratoire in 1933. It was a coaxial helicopter, contra-rotating. After many ground tests and an accident, it first took flight on 26 June 1935. Within a short time, the aircraft was setting records with pilot Maurice Claisse at the controls. On 14 December 1935, he set a record for closed-circuit flight with a 500-meter (1,600 ft) diameter. The next year, on 26 September 1936, Claisse set a height record of 158 meters (520 ft). And, finally, on 24 November 1936, he set a flight duration record of one hour, two minutes and 5 seconds over a 44 kilometer (27 mi) closed circuit at 44.7 kilometers per hour (27.8 mph).
The Fw 61 developed by Professor Henrich Focke and his team made its maiden flight in Bremen, Germany, on June 26, 1936. This event was the start of a new area in helicopter development. The first practical helicopter was born and only one year later this machine won all the official world records for helicopters.
The demonstration of the German Fw 61 prompted G&J Weir, Ltd., to abandon its Autogiro developments for the helicopter. Their second helicopter, the Weir W.6 made its first flight in Scotland in October 1939. But the U.K. government directed in mid-1940 that Weir abandon the helicopter to concentrate on other wartime production.
After building various Autogiros, Anton Flettner turned his attention to helicopters in Germany during World War II. His ultimate creation was the Flettner Fl 282 Kolibri ("Hummingbird"), which was an intermeshing rotor helicopter. First flight was on October 30, 1941. Only 24 were built by the end of the war, but it is considered the world’s first production helicopter.
By Mike Hirschberg
Go back to the calendar cover photo or check out the photo for next month.