L.Opdyke French Aeroplanes Before the Great War (Schiffer)
Deleted by request of (c)Schiffer Publishing
Cornu
Paul Cornu is often claimed to be the first man ever to take off vertically in a heavier-than-air machine. A modest retailer of cycles and cars at Lisieux in Normandy, he came of an air-minded family: his father had worked on the plans for a dirigible. In 1899, aged 18, he designed with his father a rotary engine and patented it in 1902. He also invented a steam tricycle, another gas engine, and a small car with 2 gas engines and no gearbox or differential.
In 1905 he started work on flying machines, and designed a balancing device for aeroplanes and a propelling device for helicopters. In 1906 he built a model helicopter consisting mainly of 2 horizontal propellers of the Renard type; on 4 October 1906 he managed hovering flights with a 2 hp model. By this time he had ordered a 24 hp Antoinette, delivered on 30 October.
Through vertical shafts and belts his engine drove 2 large spoked wheels less than 2' ahead of and behind the engine; a 2-blade propeller was fastened to each wheel, the blades built of spars and ribs and false ribs, all covered with fabric and mounted with substantial dihedral. At each end of the helicopter 2 similar blades were mounted as stabilizers. The pilot sat behind the engine on a 4-wheeled chassis.
The helicopter was finished in August 1907, and on the last day of the month hovered unmanned, with the engine turning at only 750 rpm and the propellers at only 70 rpm. Further tests were made starting in October in the former Duchesne-Fournet factory: of some 300 tries, only 15 were reported satisfactory. On 3 November 1907, with Cornu at the controls, the machine was said to have taken off and hovered at the height of one foot, engines turning at 850 rpm, gross weight 260 kg. On 26 March 1908 he was again reported to have flown at Coquainvilliers, near Pont Leveque, Normandy, this time in front of 200 people. As the wind was strong, Cornu asked one of his brothers to secure the helicopter by holding it; it was claimed finally to have taken off with both men aboard, hovering in the gusts of wind with difficulty about 5' off the ground; the gross weight was then 328 kg. But Jean Boulet, famous helicopter pilot and author of L'Histoire de l'Helicoptere Racontee par ses Pionniers 1907-1956 claims the Cornu was not powerful enough even to hover, and notes in addition that there are no pictures of flight or even with spectators. Boulet notes further that when Cornu had flown a 13-kilogram model helicopter, he had arranged for a notarized document with 60 signatures to attest its flight, so he seems to have known about the need for documentation!
(Span of each rotor; 6 m; lifting area: 6 sqm)
Unable really to fly with his machine, Cornu began the design of a helicoplane, but lacked funds to build it.