Page:Aerial Flight - Volume 2 - Aerodonetics - Frederick Lanchester - 1908.djvu/432

App. VIIIb. The dissipation of energy in the flight of the boomerang in all probability is not so very much different from that of a simple aerodone, and thus we may take the loss of energy as represented by the weight multiplied by Ύ times the distance traversed. The value of Ύ under the exceptional conditions in question we have

Fig. 199.

no means of calculating, but evidently if the boomerang is properly formed it will be of the same order of magnitude as the simple aerodone, or say, = .2.

Now, since the initial and final altitudes are approximately the same, we may take it that the whole of the energy expended is taken from that of initial velocity or initial rotation. Taking a