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Updated: May 26, 2025
This machine ranks as the second on the helicopter principle to achieve flight; it remained in the air for no less than the third of a minute in one of its trials. Later experimenters in this direction were Kress, a German; Professor Wellner, an Austrian; and W. R. Kimball, an American.
It has been proved that slight divergences from the course of the wind can be obtained by this means, but no real navigation of the air could be thus accomplished. Professor Wellner, of Brunn, brought up the idea of a sailing balloon in more practical fashion in 1883.
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