Memorandum presenting an overview of the development of light and small airplanes. Some of the characteristics explored include the development of airplanes of medium weight, development in countries other than Germany, development of light airplanes, general constructive fiducial lines, safety problems, the economy problem, and some special structural considerations are provided.

This report describes experiences with a rotating cylinder to explore the effects of motion and flow upon human sensory organs. One observation was that the variation of the resultant line of gravity (from gravity and centrifugal force) was not felt so strongly as might be expected. The impressions produced by the physical effects on the members of the body, especially the ones caused by the deflecting force (Coriolis force), are exactly what the laws of physics would lead us to expect, although somewhat surprising when observed in one's own body.

Report presenting an investigation of the phenomenon of knocking in gasoline engines and some of the problems that it may cause. It is of the greatest importance, not only for automobile engines, but also for every other kind of internal combustion engine, since it limits the degree of compression and the thermal efficiency and its investigation indicates ways for saving fuel.

The results that are described in this article form a complete series of tests on an airfoil fitted with front and rear slots, the rear slot being formed between the portion of the wing aft of the rear spar and the forward portion of the flap.