Supporting the aircraft

Sir George Cayley's governable parachute

The first published paper on aviation was "Sketch of a Machine for Flying in the Air" by Emanuel Swedenborg published in 1716. This flying machine consisted of a light frame covered with strong canvas and provided with two large oars or wings moving on a horizontal axis, arranged so that the upstroke met with no resistance while the downstroke provided lifting power. Swedenborg knew that the machine would not fly, but suggested it as a start and was confident that the problem would be solved. He wrote: "It seems easier to talk of such a machine than to put it into actuality, for it requires greater force and less weight than exists in a human body. The science of mechanics might perhaps suggest a means, namely, a strong spiral spring. If these advantages and requisites are observed, perhaps in time to come some one might know how better to utilize our sketch and cause some addition to be made so as to accomplish that which we can only suggest. Yet there are sufficient proofs and examples from nature that such flights can take place without danger, although when the first trials are made you may have to pay for the experience, and not mind an arm or leg." Swedenborg would prove prescient in his observation that a method of powering of an aircraft was one of the critical problems to be overcome.

During the last years of the 18th century, Sir George Cayley started the first rigorous study of the physics of flight. In 1799 he exhibited a plan for a glider, which except for planform was completely modern in having a separate tail for control and having the pilot suspended below the center of gravity to provide stability, and flew it as a model in 1804. Over the next five decades Cayley worked on and off on the problem, during which he formulated most of basic aerodynamic theory, introducing such ideas as lift and drag. He used both internal and external combustion engines, fueled by gunpowder. Later Cayley turned his research to building a full-scale version of his design, first flying it unmanned in 1849, and in 1853 his coachman made a short flight at Brompton, near Scarborough in Yorkshire.

In 1848 John Stringfellow made a successful indoor test flight of a steam-powered model, in Chard, Somerset, England.

Jean-Marie Le Bris and his flying machine, Albatros II, 1868.

In 1856, Frenchman Jean-Marie Le Bris made the first flight higher than his point of departure, by having his glider "L'Albatros artificiel" pulled by a horse on a beach. He reportedly achieved a height of 100 meters, over a distance of 200 meters.

In 1866 Jan Wnęk a Polish peasant, sculptor and carpenter is alleged to have built and flown a controllable glider. Wneks claims are largely based on a local oral tradition. Professor Tadeusz Seweryn, director of the Kraków Museum of Ethnography, claimed to have found church records substantiating these claims, but has refused to make these available for independant scrutiny.

Francis Herbert Wenham built a series of unsuccessful unmanned gliders. He found that the most of the lift from a bird-like wing appeared to be generated at the front edge, and concluded correctly that long, thin wings would be better than the bat-like ones suggested by many, because they would have more leading edge for their area. Today this reltionship is known as aspect ratio of a wing. He presented a paper on his work to the newly formed Aeronautical Society of Great Britain in 1866, and decided to prove it by building the world's first wind tunnel in 1871.^[23] Members of the Society used the tunnel and learned that cambered wings generated considerably more lift than expected by Cayley's Newtonian reasoning, with lift-to-drag ratios of about 5:1 at 15 degrees. This clearly demonstrated the ability to build practical heavier-than-air flying machines; what remained was the problem of controlling and powering the flight.

In 1871 the Frenchman Alphonse Pénaud successfully flew a model aircraft powered by twisted rubber in Paris. This was significant because the model had two features which gave it a degree of inherent stability: the rear-mounted taiplane was set at a smaller angle of incidence than the wings, and the wings were curved up at the tips, giving them dihedral. The principle of a difference in angle of incidence between the lifting surface and a stabilising tailplane was an original and important contribution to the theory of aeronautics.^[24] The use of dihedral had been worked out by Cayley, although at the time Cayleys work was largely unknown, and Pénaud had arrived at the idea independently. Rubber powered model aircraft inspired a whole generation of future flight pioneers, including the Wright brothers who were given them as toys when children.

In 1874, Félix du Temple built the " Monoplane ", a large plane made of aluminium in Brest, France, with a wingspan of 13 meters and a weight of only 80 kilograms (without the driver). Several trials were made with the plane, and it is generally recognized that it achieved lift off under its own power after a ski-jump run, glided for a short time and returned safely to the ground, making it the first successful powered flight in history, although the flight was only a short distance and a short time.

Félix du Temple's 1874 Monoplane.

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