November 8, 1881|
|Died||December 6, 1957
Nice, France 
Robert Albert Charles Esnault-Pelterie (November 8, 1881 – December 6, 1957) was a pioneering French aircraft designer and spaceflight theorist. He is referred to as being one of the founders of modern rocketry and astronautics, along with the Russian Konstantin Tsiolkovsky, the German Hermann Oberth and the American Robert H. Goddard.
He served in World War I and was made an Officier de la Légion d'Honneur.
In November, 1928, on board the Ile de France while sailing to New York City, he was married to Carmen Bernaldo de Quirós, the daughter of Don Antonio and Yvonne Cabarrus, and granddaughter of General Marquis of Santiago, Grandee of Spain, Head of the Military Household of Queen Isabella II.
He died on December 6, 1957 in Geneva.
Esnault-Pelterie developed and manufactured aeroplanes and aero engines under the name REP.
His first experiments in aviation were based on the Wright brothers 1902 glider. His first glider design was tested on a beach near Calais, but was not successful. His glider was based upon an incomplete understanding of the Wright glider, and although using a version of the wing-warping which the Wright brothers had used to control their aircraft this did not work properly and was abandoned, since he considered it dangerous. After condemning the Wright brothers' approach, he developed the concept of the aileron, fitting a pair of mid-gap control surfaces in front of the wings.
In 1906 he began his first experiments in towed flight. On 19 September 1906 he flew 500 m (1,600 ft). He made his first powered flight on October 10, 1907, a distance of 100 m (330 ft) with the REP 1. This was driven by a seven-cylinder, 30 hp air-cooled engine of his own design.
Trials of the monoplane REP 2 began on June 8, 1908. This aircraft set a record with a 1,200 m (3,900 ft) flight, reaching an altitude of 30 m (98 ft). After a modified version of this plane was flown for the last time in 1909 at Rheims, Pelterie stopped flying and instead focused on the development and manufacture of aircraft.
The Vickers R.E.P. Type Monoplane was based upon his designs, and marked the beginning of aircraft production at the later Vickers Limited. In 1912 he introduced the REP Type N and in 1914 the REP Parasol monoplane.
His family had invested heavily to fund his aircraft designs, and this had left them nearly financially ruined. However, he was the inventor of the "joystick" flight control, and owned a patent on the design. Following the war he was involved in litigation over his joystick patent. Many aircraft built during the war had used this design and the aircraft companies owed him royalties. The damages he won and subsequent royalties made him a wealthy man. This also allowed him to repay his father's significant investment.
Esnault-Pelterie designed and built his own aero engines. He also sold them under the name R.E.P. They were all of an unusual multiple-banked fan or half-radial type. The first design featured seven cylinders double-banked, with four in one bank and three in the other, and was rated at 30 horsepower (22 kW). A later model doubled them up to create a 14 cylinder quadruple-banked engine giving 60 horsepower (45 kW).
He became interested in space travel, and, not knowing of Tsiolkovsky's 1903 work, in 1913 produced a paper that presented the rocket equation and calculated the energies required to reach the Moon and nearby planets. In this talk, he proposed the use of atomic energy, using 400 kg of radium to power an interplanetary vehicle. His culminating work was L'Astronautique, published in 1930. A later version published in 1934 included details on interplanetary travel and applications of nuclear power.
On June 8, 1927, Esnault-Pelterie gave a symposium for the Société astronomique de France (French Astronomical Society) titled L'exploration par fusées de la très haute atmosphère et la possibilité des voyages interplanétaires, concerning the exploration of outer space using rocket propulsion. Jean-Jacques Barré attended this lecture, and developed a correspondence with Esnault-Pelterie on the topic of rockets.
In 1929, Esnault-Pelterie and André-Louis Hirsch, a sponsor for early astronautics in France, provided funding to the Société astronomique de France to establish the Prix REP-Hirsch (later called the Prix d'Astronautique), the first prize for astronautics in the world. The prize was awarded from 1929-1939.
In 1929 Esnault-Pelterie proposed the idea of the ballistic missile for military bombardment. By 1930, Esnault-Pelterie and Barré had persuaded the French War Department to fund a study of the concept. In 1931, the two began experimenting with various types of rocket propulsion systems, including liquid propellants. The same year he ran a demonstration of a rocket engine powered with gasoline and liquid oxygen. During an experiment with a rocket design using tetra-nitromethane he lost three fingers from his right hand during an explosion. Unfortunately their work failed to create an interest in rocketry within France.
Among his interests were horseback riding, playing golf, camping and driving cars. During his lifetime he filed about 120 patents in a variety of fields ranging from metallurgy to automobile suspension. He was the inventor of the "center stick" aircraft control and of a new type of fuel pump. He also developed the idea of rocket maneuver by means of vectored thrust.