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Da Vinci’s second flyer was a helicopter. An aërial screw 96 feet in diameter was to be turned by a strong and nimble artist who might, by prodigious effort, lift himself for a short time. Though various small paper screws were made to ascend in the air, the larger enterprise was never seriously undertaken. Many subsequent inventors developed the same project; but the fellow turning the screw always found it dreadful toil and a hopelessly futile task. Of late the man-driven helicopter has been abandoned, but the motor-driven one is very much cultivated. Scores of inventors in recent years, aided by light motors, have been trying to screw boldly skyward, and some have succeeded in rising on a helicopter carrying one man.

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Aërial Navigation
A Popular Treatise on the Growth of Air Craft and on Aëronautical Meteorology
By Albert Francis Zahm
Published in 1911
Available from gutenberg.org

Posted on

Saturday 1 January 2022

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• Technology / Transport / Air

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