Aero and Hydro Volume 3; America's Aviation Weekly (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1912 Excerpt: ...Now will be shown the action of the air on the cambered surface, the important relationship of the top of the aerocurve Fig. 6 or wing to the under surface, the shapes most in use, the relation of the lift to the drift of same, probable effect of outline, relation of length to breadth, the effect of camber and variation of the center of pressure with angle. "A" of Fig. 7 is a photographic reproduction of the streamlines flowing around a typical monoplane wing. It clearly shows the upward trend that the air currents take at a considerable distance in advance of the leading edge of the plane and explains why a cambered plane will lift even at a negative angle of from two to three degrees. The angle of flow upward, at one-quarter the width of the plane in front of the leading edge is in this particular case about Ave degrees, the partial vacuum formed on the back of the plane is clearly shown and the increased pressure on the face is equally plain. "B" Fig. 7 shows the effect of superimposing one plane above another, as in biplane practice, this photograph gives optical demonstration of the reason why biplanes do not carry more than 80 per cent of the load per square foot of area that is carried by a monoplane. To be more specific, experiments show that curved surfaces one above the other, inclined at small angles of incidence, affect the lifting power of each other according to their distance apart vertically, or, as commonly expressed, the gap of the planes. For instance, for a camber of 1 in 13.5, if the distance of the upper plane from the lower plane is two-thirds the chord or width of the planes, then the lift of each plane per square Begun, January 13, 1911, Vol. Ill, No. 15. more than one plane is used one above the other, as in bip...