"The problem of turbulence in aerodynamics is at present being attacked both theoretically and experimentally. In view of the fact however that purely theoretical considerations have not thus far led to satisfactory results the experimental treatment of the problem is of great importance. Among the different measuring procedures the hot wire methods are so far recognized as the most suitable for investigating the turbulence structure" (p. 1).

"It is known that compression shocks which lead from supersonic to subsonic velocity cause the flow to separate on impact on a rigid wall. Such shocks appear at bodies with circular symmetry or wing profiles on locally exceeding sonic velocity, and in Laval nozzles with too high a back pressure. The form of the compression shocks observed therein is investigated" (p. 1).

The Russian AM 35 and AM 38 aircraft engines have superchargers with a swirl throttle, which appears to be a purely Russian development. This paper gives the results of test runs of the two engines, including the effects of the swirl throttle on engine performance.

The characteristics of the position and form of the transition surface through the critical velocity are computed for flow through flat and round nozzles from subsonic to supersonic velocity. Corresponding considerations were carried out for the flow about profiles in the vicinity of sonic velocity.

"The NACA 23012-4 airfoil was investigated for the purpose of increasing lift by means of blowing out air from the wing, in conjunction with the effect of plain flap of variable contour and slotted flap of 25 percent chord length. The wing also was provided with a hinged nose, to be deflected at will. Air was blown out from the wing immediately in front of the flap; also at the opening between wing and hinged nose,tangentially to the surface of the wing" (p. 1).

"There are investigated the problems of the flow of a supersonic jet out of a vessel with plane side walls and the problem of the supersonic flow about a wedge when there is a zone of local subsonic velocities ahead of the wedge" (p. 1).

"The problem of the intake of air is treated for a missile flying at supersonic speeds and of changing the kinetic energy of the air into pressure with the least possible losses. Calculations are carried out concerning the results which can be attained. After a discussion of several preliminary experiments, the practical solution of the problem at hand is indicated by model experiments. The results proved very satisfactory in view of the results which had been attained previously and the values which were anticipated theoretically" (p. 1).

In accord with me test program (published in reference 7) the wing in question is briefly designated as No. 5. It differs from the rectangular wing discussed in reference 7 by its taper and from the 35 degree swept-back trapezoidal wing treated in reference 8 by the absence of sweepback.

"Some aerodynamic relations are derived which exist between two infinitely long airfoils if one is in a straight flow and the other in oblique flow, and both present the same profile in the direction of flow" (p. 1).

"The report UM No. 1023/1 which presented the results of measurements for a series of trapezoidal wings was the beginning of a series on wings with aspect ratio 1 to 3 and various contours. In report No. 1023/1 the aspect ratio (Lambda = 4/3) remained the same; the tapering was modified. The present report gives the results of the series of elliptic wings. Here the aspect ratio varies from 1 to 2 with the sweepback. The contour is formed by elliptic arcs. The influence of sweepback and contour upon the neutral point is shown" (p. 1).

"Maintenance of a laminar boundary layer by suction was suggested recently to decrease the friction drag of an immersed body, in particular an airfoil section. The present treatise makes a theoretical contribution to this question in which, for several cases of suction and blowing, the stability of the laminar velocity profile is investigated. Estimates of the minimum suction quantities for maintaining the laminar boundary layer and estimates of drag reduction are thereby obtained" (p. 1).

This paper gives an overview of equations for vibration and flutter affecting airplane wings in nonstationary flow.

The present report contains three-component forces and mass-flow measurements on a jet nacelle at small inlet-velocity ratios v(sub A)/v(sub o) < 1. The mass-flow measurement on two cross sections of the nacelle demonstrate the local-velocity distribution with varying flow and angle of attack.