Unidentified Flying Objects: Project "Grudge" (Technical Report No. 102-AC 49/15-100)

sims may so nately, the objects were actually either of different sizes, or more likely, that they were far enough from the observers so that binocular vision produced no stereopeople effect; this only means that they were farther off than almost thirty feet; 2) since objects seen to disappear behind trees, buildings, clouds are, they are large enough to be visible at the range of those recognizable objects.

How it is obviously of prime importance to estimate the size and mass of the observational objects. This may be possible to some extent if it is perishable to assume that they obey the laws of physics. Since the objects have not been observed to produce any physical effects, other than the one case in which a cloud was evaporated along the trajectory, it is not certain that the laws of mechanics, for instance, would be sufficeent.

but suppose that mechanical laws alone are sufficient. Then the following example is sufficient proof that at least a length could, in principle, be determined; suppose a single penculon were observed supposed in the sky; then after observing its frequency of oscillation, we could deduce from the laws of mechanics its precise length.

This suggests that something could be deduced from the observed fluttering motion of some of the objects of group 1. Assume that we know the angular frequency and angular amplitude of this fluttering motion (they can be measured in principle from a motion picture). Then for purposes of calculation assume the object to be thirty feet in diameter, to be an rigid as a normal aircraft wing of 30 foot span, to be constructed of material of the optimum weight-strength ratio and to be a structure of most efficient design. It is now possible to calculate how heavy the object must be carefully to remain rigid under the observed angular motion. Let the calculation be made for a plurality of assumed sizes 1, 2, 4, 6, 16, 32, 64 ---- up to any