Unpowered Aircraft

An ornithopter (from Greek ornithos "bird" and pteron "wing") is an aircraft that flies by flapping its wings. Designers seek to imitate the flapping-wing flight of birds, bats, and insects. Though machines may differ in form, they are usually built on the same scale as these flying creatures. Manned ornithopters have also been built, and some have been successful. The machines are of two general types: those with engines, and those powered by the muscles of the pilot.

*how it begun ?

Some early manned flight attempts may have been intended to achieve flapping-wing flight though probably only a glide was actually achieved. These include the flights of the 11th-century monk Eilmer of Malmesbury (recorded in the 12th century) and the 9th-century poet Abbas Ibn Firnas (recorded in the 17th century). Roger Bacon, writing in 1260, was also among the first to consider a technological means of flight. In 1485, Leonardo da Vinci began to study the flight of birds. He grasped that humans are too heavy, and not strong enough, to fly using wings simply attached to the arms. Therefore he sketched a device in which the aviator lies down on a plank and works two large, membranous wings using hand levers, foot pedals, and a system of pulleys.
The first ornithopters capable of flight were constructed in France. Jobert in 1871 used a rubber band to power a small model bird. Alphonse Pénaud, Abel Hureau de Villeneuve, and Victor Tatin, also made rubber-powered ornithopters during the 1870s. Tatin's ornithopter (now in the US Air & Space Museum) was perhaps the first to use active torsion of the wings, and apparently it served as the basis for a commercial toy offered by Pichancourt c. 1889. Gustave Trouvé was the first to use internal combustion and his 1890 model flew a distance of 70 metres in a demonstration for the French Academy of Sciences. The wings were flapped by gunpowder charges activating a bourdon tube.
From 1884 on, Lawrence Hargrave built scores of ornithopters powered by rubber bands, springs, steam, or compressed air. He introduced the use of small flapping wings providing the thrust for a larger fixed wing. This eliminated the need for gear reduction, thereby simplifying the construction.

E.P. Frost made ornithopters starting in the 1870s, first models power by steam engines then in the 1900s an internal combustion one large enough for a person but which did not fly.

In the 1930s, Alexander Lippisch and the NSFK in Germany constructed and successfully flew a series of internal combustion powered ornithopters, using Hargrave's concept of small flapping wings, but with aerodynamic improvements resulting from methodical study.
Erich von Holst also working in the 1930s, achieved great efficiency and realism in his work with ornithopters powered by rubber band. This includes perhaps the first success of an ornithopter with a bending wing, intended to more closely imitate the folding wing action of birds although it was not a true variable span wing like birds have.


Around 1960, Percival Spencer successfully flew a series of unmanned ornithopters using internal combustion engines ranging from 0.020-to-0.80-cubic-inch (0.33 to 13.11 cm³) displacement, and having wingspans up to 8 feet (2.4 m). In 1961, Percival Spencer and Jack Stephenson flew the first successful engine-powered, remotely piloted ornithopter, known as the Spencer Orniplane. The Orniplane had a 90.7 inches (2,300 mm) wingspan, weighed 7.5 pounds (3.4 kg), and was powered by a 0.35-cubic-inch (5.7 cm³) displacement 2-stroke engine. It has a biplane configuration, to reduce oscillation of the fuselage.

To sum up

Ornithoper is not really usefull for transportation nowdays. But people still use it for hobby because it is reaiiu fun to play with it or when you become expert on it you can make your own ornithoper model. My writing is now finished but to add  more fun I will show you some video about ornithoper.