Note presenting a method by which the total temperature of the gases at the combustion-chamber outlet of a ramjet engine may be determined from the loss in total pressure measured across the combustion chamber. Values of total-temperature ratio across the combustion chamber of a 20-inch ram jet were obtained in the altitude wind tunnel over a range of pressure altitudes.

Note presenting an investigation of three ceramic coatings applied to four heat-resistant alloys that are tested for effectiveness in preventing carbon absorption under strongly carburizing conditions (box carburizing).

"Three-dimensional interaction surfaces are presented for the computation of elastic buckling stresses for an infinitely long flat plate subjected to combinations of bending, shear, and transverse compression in its plane - a loading approximating that occurring in a shear web. Surfaces are presented for two sets of edge conditions: both edges simply supported and lower edge simply supported, upper edge clamped. Present results are in good agreement with data for one-load and two-load limiting cases previously published" (p. 1).

Note presenting an investigation to determine the effect of spot-weld quality on the corrosion behavior of panels fabricated from alclad 24S-T3, 24S-T3, R-301-T6 of 0.020-inch thickness. The preparation and examination of each of the specimens is described. Results regarding effect of exposure on weld shear strength, effect of exposure on normal tensile strength of welds, and a metallographic examination of spot welds are provided.

Report presenting a study of the Von Kármán momentum theorum with respect to its application to turbulent boundary layers in a positive pressure gradient. The results indicate that the streamwise derivative of the turbulent longitudinal momentum may be large near the separation and therefore should be considered when the momentum theorum is used for turbulent boundary layers near separation.

"A circulating system for radioactive tritium was constructed, assembled, and tested. The results showed that the pumping speed of the system was too low for use. Therefore, bombardments in the cyclotron with tritium particles would not be made during the course of this project" (p. 1).

Report presenting a theoretical analysis of acceleration restrictors which work on the principle of stopping the upward motion of the elevator when the signal from an acceleration-sensing device reaches a certain value.

Note presenting two jet-propelled airplanes that were flown in rough air to investigate the effects of center-of-gravity location on gust loads. Data were obtained at centers of gravity of 20.9 and 27.5 percent mean aerodynamic chord for incremental load factor up to 1 g. The results indicated approximately a 10-percent reduction in loads for a forward movement of the center-of-gravity location of 6.6 percent mean aerodynamic chord.

Note presenting experimental results that shed light on the assumptions that have been made in several attempts to bridge the gap between physical and mathematical theories of plasticity. The experimental results are compatible with, but do not verify, the conception that plastic deformation in strain-hardening materials is primarily due to slip. Results regarding the mechanism of plastic deformation, development of slip in a polycrystal, number of slip systems in operation, and equality of stresses or strains in all grains are provided.

Report presenting a wide distribution in the angular orientation of slip lines, which is generally observed in various grains of a metal subjected to plastic deformation. Results regarding a comparison of theoretical and experimental results and consequences of the present investigation relative to the slip theory of plasticity are provided.

Report presenting predictions of the dynamic longitudinal stability of an airplane with autopilot and comaprisons with measured flight frequency and transient responses for three airspeeds and various autopilot settings of displacement and rate of displacement feedback. Results regarding the aircraft transfer function, autopilot frequency response, hinge moment, autopilot gearing, and autopilot-aircraft combination are provided.

Explicit expressions are developed which yield the Mach number and pressure distributions on the surfaces of pointed nonlifting bodies of revolution operating at high supersonic airspeeds and at values of the hypersonic similarity parameter (ratio of free-stream Mach number to slenderness ratio) greater than 1. Very simple explicit expressions are obtained for these distributions in the special case of slender bodies. In the case of cones, the analytic solutions accurately define the entire flow field over a wide range of free-stream Mach numbers and apex angles.

From Introduction: "A theoretical analysis of the factors involved in the measurement of the temperature of gaseous combustion products by the X-ray absorption method is presented herein."

"The differential equations of the bending of sandwich plates were integrated to obtain the deflections when the four edges of the plate are simply supported and the loading consists of either a uniformly distributed transverse load or a concentrated load applied at the center of the panel. The deflection patterns are shown in diagrams and the maximum deflection of the plate is presented in a number of graphs" (p. 1).

Results are presented of wind-tunnel tests made at low speed of various small-scale models of sweptback, sweptforward, and yawed wings. The tests covered changes in aspect ratio, taper ratio, and tip shape. Some data were obtained with high-lift devices on sweptback wings and with ailerons on sweptforward wings. The data have been briefly analyzed and some comparisons have been made with the available theory.

From Summary: "An investigation has been made of a complete airplane model having a wing with the quarter-chord line swept back 40 degrees, aspect ratio 2.50, and taper ratio 0.42 to determine its low-speed stability and control characteristics. The longitudinal stability investigation included stabilizer and tail-off tests with different wing dihedral angles (Gamma = 0 degrees and Gamma = -10 degrees) over an angle-of-attack range for the cruising and landing configurations and tests. with a high horizontal-tail location (Gamma = -10 degrees) for the cruising configuration. Tests were made of the wing alone and to determine the effect of wing end plates in pitch."

Report presenting various investigations of single-degree-of-freedom pitching oscillations of a wing in potential flow. It demonstrates by theoretical calculations that single-degree-of-freedom control-surface flutter is possible. The effects of structural damping, aerodynamic balance, axis of rotation, and compressibility are provided.

"The pitching-moment derivatives Cmq and Cma at supersonic speeds are developed for a slender-delta-wing and slender-body combination having no afterbody. By drawing an analogy between the aerodynamics of the wing-body section of the combination and the aerodynamics of a delta wing alone, the results for the slender-delta-wing and slender-body combintion are modified to the extent that approximate solutions for Cmq and Cma for broad-delta-wing and slender-body combinations can be obtained" (p. 1).

Note presenting two flexible wings, one with 45 degrees sweepback and the other unswept, to determine their performance in roll. Rolling moments due to aileron deflection, damping derivatives in roll, and free-rolling angular velocities due to aileron deflection were obtained at various speeds including, when possible, the aileron reversal speed. The results showed that, when designed for equal stress, the swept wing had generally higher reversal speeds than did the straight wing.

Report presenting the results of an investigation of water-vapor condensation shocks in the air passing through supersonic tunnels. Criterions for condensation-free flow are established by correlating experimental observations with the Volmer theory of nuclei formation. Results regarding the condensation-free criterions, scale effect, physical appearance of condensation shock, and practical considerations for tunnel design are provided.

Report presenting a theoretical analysis of the effect of several auxiliary damping devices on the lateral stability and controllability of a high-speed aircraft. The systems investigated included stabilization devices which deflect the rudder of an auxiliary surface proportional to the yawing velocity, rolling velocity, or rolling acceleration and one which deflects both aileron and rudder proportional to the rolling velocity.

Report presenting testing on six large 24S-T3 aluminum alloy sheet specimens containing various notches and fillets to determine their stress concentration factors in the elastic and plastic ranges. Results regarding elastic stress concentration factors, plastic stress concentration factors, a suggested formula, and stress and strain distributions are provided.

"Theoretical analyses are presented of the effect of slip on the flow of a rarefied gas near a stagnation point and in a boundary layer on a flat plate. The results indicate that the stagnation pressure is increased because of the effect of slip but that there is a negligible effect on the flat-plate skin-friction coefficient in the range of application of the analysis" (p. 1).

Report presenting an experimental investigation of some effects of the variations in several parameters, including fluid density, on the flutter characteristics of light uniform cantilever wings. The wings tested covered a variety of positions of the elastic axis and center of gravity and values of aspect ratio 8, 6, and 4. Results regarding the experimental and analytical investigations, relative-density parameters, and dynamic pressure at flutter are provided.