Happy Birthday Otto Lilienthal!

Eine Flugmaschine zu erfinden bedeutet wenig; sie zu bauen schon mehr; aber sie zu fliegen, das ist das Entscheidende.

To invent an airplane is nothing. To build one is something. But to fly is everything.

Alles Fliegen beruht auf der Erzeugung von Luftwiderstand, alle Flugarbeit besteht in der Überwindung von Luftwiderstand.

All flight is based upon producing air pressure, all flight energy consists in overcoming air pressure.

Die Macht des Verstandes, o, wend' sie nur an, sie wird auch im Fluge Dich tragen!

I, too, have made it a lifelong task of mine to add a cultural element to my work, which should result in uniting countries and reconciling their people.

Es kann Deines Schöpfers Wille nicht sein, Dich, Ersten der Schöpfung, dem Staube zu weih'n, Dir ewig den Flug zu versagen!

Artificial flight may be defined as that form of aviation in which a man flies at will in any direction by means of an apparatus attached to his body, the use of which requires personal skill.

Es gibt wohl kaum einen Menschen, welcher sich nicht hin und wieder über das Fliegen seine Gedanken macht.

Gradual development of flight should begin with the simplest apparatus and movements, and without time complication of dynamic means.

Genieße jede Sekunde deines Lebens, denn du bist länger tot als lebendig.

The contrivances which are necessary to counteract the wind effects can only be understood by actual practice in the wind.

Das eigentliche Geheimnis des Vogelflugs ist in der Wölbung des Vogelflügels zu erblicken.

The supporting powers of time air and of the wind depend on the shape of the surfaces used, and the best forms can only be evolved by free flight through the air.

Opfer müssen gebracht werden.

Sacrifices must be made!

Ich muss etwas ausruhen, dann machen wir weiter.

Particular honour belongs to those who believed in the possibility of mechanical flight when all the world was against them; not the visionaries because they hoped for it merely, but those who by sheer force of intellect perceived the means by which it could be accomplished and directed their experiments along the right path. ... The name of Lilienthal is now among the most honoured, but curiously his own countrymen were the last to recognize the value of his work.

No one can realize how substantial the air is, until he feels its supporting power beneath him. It inspires confidence at once.

We returned home, after these experiments, with the conviction that sailing flight was not the exclusive prerogative of birds.

One can get a proper insight into the practice of flying only by actual flying experiments. . . . The manner in which we have to meet the irregularities of the wind, when soaring in the air, can only be learnt by being in the air itself. . . . The only way which leads us to a quick development in human flight is a systematic and energetic practice in actual flying experiments.