Page:Aerial Flight - Volume 2 - Aerodonetics - Frederick Lanchester - 1908.djvu/54

 other experiments with the same model, say 55 m.h., this length of time corresponds to a flight of 725 yards.

There are two possible explanations of this anomalous flight. (1) That the aerodone was actually soaring after the manner of an albatros or gull. (2) That the initial kinetic energy, being due to the velocity of the aerodone relatively to the wind, is much greater when the aerodone is launched in the teeth of a gale, and so the energy disposable in the flight will be greater in a proportionate degree.

Both these explanations are possible, and either would, within limits, account for an enormous increase in the observed range of flight. At first sight alternative (1) seems most unlikely; it appears to imply an exercise of intelligence not possible for an inanimate thing. Later experiments, however, show that it is by no means impossible for a simple aerodone to perform true soaring evolutions, and that it is not at all improbable that this was actually the case in the flight in question. On the other hand alternative (2) alone is almost sufficient to account for the additional energy as evidenced, so that the correct explanation of the case in point must be regarded as uncertain.

'''§ 16. Author's Experiments. Remarks and Summary.'''—If we define the line of flight of an aerodone as the path of its mass centre, it is one feature of the designs employed by the author, and in the models discussed in § 9, that the centre of resistance is substantially coincident with the line of flight; the same is approximately true of the soaring birds. Attention is directed to this point on account of the fact that many inventors have proposed acentric types of aerodrome, in which the weights carried have been suspended some distance beneath the supporting member; this is typically the case in the captive machine of Sir Hiram Maxim, a diagrammatic illustration