 | CHAPTER III.
MECHANICAL BIRD ACTION. Flying Machines: Construction and Operation: A Practical Book Which Shows, in Illustrations, Working Plans and Text, How to Build and Navigate the Modern Airship. |  |
Another Simple Illustration.
Another simple means of illustrating the principle of flying machine operation, so far as sustentation and the elevation and depression of the planes is concerned, is explained in the accompanying diagram.
A is a piece of cardboard about 2 by 3 inches in size. B is a
piece of paper of the same size pasted to one edge of A. If you bend the
paper to a curve, with convex side up and blow across it as shown in
Figure C, the paper will rise instead of being depressed. The dotted
lines show that the air is passing over the top of the curved paper and
yet, no matter how hard you may
Principle Upon Which Aeroplane Works.
[Description: Black and white illustration: Top: piece of paper attached to
piece of cardboard. Middle: person blowing air onto paper with convex
side up. Bottom: same, but with concave side up.]
In Figure D we have an opposite effect. Here the paper is in a curve exactly the reverse of that shown in Figure C, bringing the concave side up. Now if you will again blow across the surface of the card the action of the paper will be downward—it will be impossible to make it rise. The harder you blow the greater will be the downward movement.
| CHAPTER III.
MECHANICAL BIRD ACTION. Flying Machines: Construction and Operation: A Practical Book Which Shows, in Illustrations, Working Plans and Text, How to Build and Navigate the Modern Airship. | |