Asbóth, Oszkár

(Pankota, March 31st, 1891 – Budapest, February 27th, 1960)

Asbóth, Oszkár

Oszkár Asbóth is known primarily for his helicopter experiments; the true results of his activity were the development and improvement of aeroplane propellers.

At a very young age began to explore the possibilities of human flight. First he saw aeroplane propellers in French magazines from the years 1907 and 1908. Propellers made of wood piqued his interest which were first applied by Emil Némethy from Arad in 1900 before the Wright brothers, as a low revolution number low load propeller. Like most of the pioneers of aviation he was confronted with the challange of stabilising the movement of the aeroplane, and to this end developed numerous devices.

He finished his studies at Arad, Transylvania (today in Romania). He was only 18 when he built his first glider pulled up into the air by a motorcycle. Asbóth's main desire was the creation of the rotory-wing aircraft (helicopter) which rises into the air without a take-off run and is able to hover in the air. In this area only the French Paul Cornu's attempt was considerable in 13th November 1907.

He designed an engine-driven plane and patented an automatic stabilizer, which was implemented by the Westinghouse Motorcar Factory in Arad founded in 1908.

In 1910, Asbóth participated in a tender invited by the Austro-Hungarian Defense Ministry for fighting planes in which, he and his other four colleagues were honourably mentioned. He presented his stabiliser at the international air meeting held in Vienna. In 1912, he received the license for "producing aeroplanes"; in this way the first aeroplane manufacturing company was established in Hungary.

In June 1915, he started the planning of a new propeller – the so-called Asbóth propeller – at the Aeroplane Works of Fischamend and developed a series of propellers of this kind.

In 1916, an air-tunnel for aeroplane experiments was built in Fischamend, which was the largest in the world at that time. Tódor Kármán was appointed as the head of the institute. For experiments, the propellers developed by Oszkár Asbóth – who became the head of propeller workshop – were used. Asbóth constructed and tested some 1500 propellers in the wind channel of the factory. He had a clear understanding of the fundamental principles controlling propeller development and production and was soon able to patent his own design for more efficient, straight-edged propellers, which could also be produced more efficiently. For the mass production of his propellers, he founded the First Propeller Works in 1918.

His measuring results offered the possibility of calculating the flying speed and take-off speed of helicopters in a reliable way. He set the rules forming the bases to design, calculate and produce propellers (rotors) for any power and rotational speed.

He continued his helicopter experiments at the Misura Bodywork Factory in Hungary. On September 9, 1928, he took off vertically with his helicopter powered by a 120 HP nine-cylinder engine and propelled by two wooden propellers, each 4.35 meter in diameter, placed parallel above each other and rotating in opposite direction. Tires were replaced by four footballs to provide sufficient flexibility for landing. During the first flight, after 1100 rotations the plane swiftly took off, at ten meters stopped, hovered for some ten minutes, remained absolutely stable around all axes, than smoothly descended.

The two large wooden propellers raised Asbóth´s device into the air together with its pilot more than 200 times and hovered in the air for almost one hour, which was a great achievement, but because of their rigid propellers Absóth´s „helicopters" became unstable when moving forward or when subjected to a strong side wind.

His ability with the pen and knowledge of foreign languages provided that news of his experiments travelled round the world and his experiments were considered to the first successful flights that the world had ever seen. By his good business sense Absóth was able to profit from his inventions. The British Air Ministry got an option of purchase of his helicopter in 1938.

In Hungary Absóth performed experiments with propellers-driven automobiles, which were broken by a fatal accident due to a structural defect. He was accused to be responsible and he was condemned. Following this set-back Asbóth took advantage of his international reputation and was able to continue his developing work on helicopters, working for French, English and German companies.

In 1941 he left Germany and returned to Hungary, where he experimented on boats powered by aircraft propellers and contributed to scientific journals. He continued this work after 1945 and worked as an expert for Innovations Implementation Company until his death.

For his work on the development of aircraft propellers and his experimental work in general he received several Hungarian and international awards. At the 25th anniversary of the maiden take-off with his helicopter, the Federation Aeronautique Internationale recognised his lifetime achievements in aeronautics with the Paul Tissander diplom.

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