version française

[home]  [general synopsis]  [preceding synopsis]  [forums]  [modelstories]  [library]  [links]

Otto Lilienthal: (1848-1896)
the experimenter.

by Philippe Ballarini

translation: Michel Léveillard

Born on may 24th 1848 in Anklam (Pomerania), Otto Lilienthal is without any doubts, one of the patriarch of modern aviation. Like many of those "flying fools" who gave wings to the world, he was fascinated early in life by human flight. At the young age of sixteen, he conducted experiments with large rudimentary gliders (at night), with the help of his Brother Gustav. As many other precursors of his era, he became interested in "flopping wings", and after graduating as an engineer, he published in 1889 a fundamental work for the future of aviation: "Der Vogelflug als Grunglage der Fliegenkuntst" (The flight of the birds as a basis for the art of flight). It was a work that would later on in life echo important theories about flying. As Marey, Lilienthal was interested by the flight of the birds, and as the unfortunate Mouillard, he was one of the firsts to demonstrate the importance of the wing's camber.

Lilienthal had understood, long before many of his contemporaries, that flight stability would be achieved with a cambered airfoil wing. This fact however was not the only discovery in his studies. It became evident to Lilienthal, that a flying machine would be useless, if it could not be controlled. Going against the consensus of the era, he did not believe in power flight, preferring to pursue his experiments with gliders.

"Let's learn about the science of flight, let's learn how to fly, let's experiment and perfect gliders; powered flight will follow later on." This statement is without any doubts how we can summarize Lilienthal's philosophy about flying.
The following statement was written in his own words:
"During free flight in the air mass, there are many phenomena never encountered elsewhere; particularly those related to the wind, and which must be considered in the construction, and in the utilization of the flying machines….The only possibility for a rapid solution to human flight must be a systematic approach by experimenting with "real time" flight."

Obsessed with experimentation, Otto Lilienthal did not rely on empirical theories, and his machines were the results of many computations. His working method would later on bring major contributions to aeronautical science, and permitted him to produce very sophisticated gliders despite their rudimentary appearance. All his gliders were built with a structure made either of bamboo or rattan, and covered with cotton linen. (During this time period, we were still a long way of utilizing carbon fiber and synthetic materials). The plans for all his flying machines, (aboard which he performed over two thousand gliding flights) are basically the same.

Mainly, Lilienthal built monoplanes with a wingspan of about seven meters, on which he suspended himself with his elbows and forearms.
Whereas other precursors such as Langley, or Ader pursued the construction of machines capable of only a few bounces in the air with no maneuvering capabilities, Lilienthal was able to modify his trajectory, by turning, and even sometimes attaining an altitude greater than his "takeoff" point. In fact, he was developing airplane control (pilotage), neglected by his peers.

After performing some "planements" (meaning gliding flights, a term used in that era), in Werder and in Steglitz, Lilienthal had a special, artificial conic hill built in Lichterfelde, in the Berlin suburbs. From there, he could always find favorable winds to perform his glides. He also invented a small carbonic acid motor, with which he could control the wing's extremities, somewhat as the birds do with their feathers, but he would never have the time to experiment this idea.
To reduce the wingspan of his gliders, he began building biplanes that would have eventually used this concept. Unfortunately, on August 9th 1886, the top wing of his latest prototype broke off, and Lilienthal fell from a height of 17 meters. He died shortly thereafter of his wounds after uttering his last words: "Opfer müssen gebracht werden!" roughly meaning: "Victims are necessary", or "Sacrifices must be made."

Lilienthal's work and experiments had a deep impact on his contemporaries; in particular with Chanute and the Wright Brothers. Lilienthal is not only one of the Father of aviation, he invented piloting, the controlling of aircraft. In any case, he was the first man to have maneuvered in flight, an "heavier than air" machine.

Otto Lilienthal is not only an important person in aviation's history, he was also preoccupied with social progress, especially with the employees of his factory. Technical progress of his era was also one of his subjects of research; he had worked on a small steam engine designed for craftsmanship. Surprisingly, one of his inventions survives him to this day all over the world: the wood blocks construction set. Certain  "Ankersteinbaukasten" models have not change in a century!

© Aerostories, 2000.

Otto Lilienthal
Charles Dollfus Collection.

Excerpts of Lilienthal's patent in 1895
Charles Dollfus Collection.

Otto Lilienthal was without any possible doubts, skilful and audacious. Those attribute alone however are not sufficient to explain the impact of his work. He was the first man to be photographed in flight aboard an "heavier than air" flying machine. "L'Illustration" Document  Click!

Lichterfelde 1895: the end of one of Lilienthal's gliding flight. Body motions permitted to modify the balance, and the glider's trajectory. "L'Illustration" Document   Click!

Lichterfelde 1895: the end of one of Lilienthal's gliding flight. Body motions permitted to modify the balance, and the glider's trajectory.  "L'Illustration" Document    Click!

A surprising sight: Lilienthal gets ready to launch himself from the artificial hill he had built specifically for that purpose. "L'Illustration" Document   Click!

Ultimate evolution of Lilienthal's gliders: his 1896 biplane. It is the rupture of the upper wing that will be the cause of his death. 
"L'Illustration" Document

Who remember that Otto Lilienthal the "inventor" of aircraft piloting, was also the creator of a wood construction set, still in existence more than a century after his fatal fall?

Ankersteinbaukasten Gmbh. Document .