Report presenting a small-scale transonic investigation of a semispan wing sweptback 45 degrees and of aspect ratio 4 with combinations of nose-flap deflections and wing twist in the high-speed 7- by 10-foot tunnel over a range of Mach numbers. Lift, drag, and pitching-moment data were obtained for several different configurations.

"This report presents the results of wind-tunnel tests of a 0.22-scale model of the North American XP-82 airplane with several modifications designed to reduce the buffeting of the airplane. The effects of various modifications on the air flow over the model are shown by means of photographs of tufts. The drag, lift, and pitching-moment coefficients of the model with several of the modifications are shown" (p. 1).

Characteristic velocities of six single-element injectors that separately varied propellant spreading and mixing were measured over a range of oxidant-fuel weight ratios of 2 to 7. Hydrogen inlet temperature was -320 degrees F. Injectors that both mixed and spread the propellants had the highest characteristic-velocity efficiency. Spreading of either propellant produced about the same increment efficiency. The increase in efficiency due to mixing was relatively small. With similar injectors, oxygen-hydrogen required about 0.2 to 0.5 of the combustor volume of oxygen-heptane for the same efficiency.

"An analysis is presented of the influence of wing aspect ratio and tail location on the effects of compressibility upon static longitudinal stability. The investigation showed that the use of reduced wing aspect ratios or short tail lengths leads to serious reductions in high-speed stability and the possibility of high-speed instability" (p. 1).

Memorandum presenting an investigation made to valuate the effects of vertical height of the horizontal tail on the static longitudinal stability of a model with a wing with 35 degrees of sweepback, an aspect ratio of 4.5, a taper ratio of 0.5, and NACA 64A010 sections. The investigation also included the effects of adding a partial-span, leading-edge chord extension to the outer portions of the wing. Results regarding the effect of tail height, wing-wake and local downwash measurements, and effect of a leading-edge extension are provided.

An experimental and analytical investigation of the flutter of sweptback cantilever wings is reported. The experiments employed groups of wings swept back by rotating and by shearing. The angle of sweep range from 0 degree to 60 degrees and Mach numbers extended to approximately 0.85. A theoretical analysis of the air forces on an oscillating swept wing of high length-chord ratio is developed, and the approximations inherent in the assumptions are discussed. Comparison with experiment indicates that the analysis developed in the present report is satisfactory for giving the main effects of sweep, at least for nearly uniform cantilever wings of high and moderate length-chord ratios.

Report discussing the mutual interference effects of tail surfaces and a stern propeller on a model of the XB-42.The main focus was to determine the effect of tail surface-propeller spacing upon the periodic tail surface loading coincident with propeller blade passage.

Memorandum describing preliminary investigations of two 3-inch-diameter slotted test sections over a range of pressure ratios from 1.3 to 10.0. The two test sections varied based on the number of slots and amount of open space, but they showed no appreciable difference in performance. Results regarding the slots with no chamber around the test section and with a closed chamber around the test section are provided.

Report presenting an investigation of the low-speed, power-off static longitudinal stability and control characteristics of a canard model with a triangular wing and horizontal tail in the free-flight tunnel. Results regarding the horizontal tail used to overcome change in stability and horizontal tail used for longitudinal control are provided.

Report presenting a theoretical method for calculating heat transfer in the laminar boundary layer on yawed infinite cylinders in compressible flow. The method can be applied to a cylinder of arbitrary cross section and arbitrary chordwise wall-temperature distribution. The variation in local heat transfer around the surface of the cylinder was found to have little functional dependence on yaw angle or wall temperature.

"Flight tests were conducted on a R-2800-21 engine in the P-47G airplane to determine the effect on the wall temperatures of cylinder 10 of throttling the charge in the intake pipe and of injecting a water-ethanol coolant into the intake pipe. Cylinder 10 was chosen for this investigation because it runs abnormally hot (head temperatures of the order of 45 F higher than those of the next hottest cylinder) at the medium and high-power conditions. Tests with interchanged cylinders showed that the excessive temperatures of cylinder 10 were inherent in the cylinder location and were not due to the mechanical condition of the cylinder assembly" (p. 1).

"An investigation was conducted to determine the effect of turbine-disk cooling with air on the efficiency and the power output of the radial-flow turbine from the Turbo Engineering Corporation TT13-18 turbosupercharger. The turbine was operated at a constant range of ratios of turbine-inlet total pressure to turbine-outlet static pressure of 1,5 and 2.0, turbine-inlet total pressure of 30 inches mercury absolute, turbine-inlet total temperature of 12000 to 20000 R, and rotor speeds of 6000 to 22,000 rpm, Over the normal operating range of the turbine, varying the corrected cooling-air weight flow from approximately 0,30 to 0.75 pound per second produced no measurable effect on the corrected turbine shaft horsepower or the turbine shaft adiabatic efficiency" (p. 1).

Report presenting an investigation to determine the overall performance of the three-stage turbine from the J71 turbojet engine. The turbine operated with a maximum brake internal efficiency of approximately 0.84 at an equivalent overall pressure ratio of approximately 3.6 and an equivalent rotor speed of about 110 percent of the equivalent design value.

In accordance with a request of the Bureau of Aeronautics, Navy Department, tests were performed in the Langley 20-foot free-spinning tunnel to determine the spin and recovery characteristics of a 1/24 scale model of the Grumman XTB3F-1 airplane. The airplane is a two-place, midwing torpedo bomber equipped with a tractor propeller and an auxiliary jet engine. The effect of control setting and movement on the erect and inverted spin and recovery characteristics of the model were determined for the normal loading.

Report presenting an investigation of the Reynolds number for transition on the outside of a hollow cylinder with heat transfer from the boundary layer to the wall at Mach number 6.9. At a given Mach number, it appears that the Reynolds number based on leading-edge thickness is an important parameter in comparisons of flat-plate transition data from various installations.

"About 500 additional references pertaining to hydrodynamic design of seaplanes have been compiled, and the information is presented in the form of abstracts classified under six main headings:GENERAL INFORMATION, HYDROSTATICS, HYDRODYNAMICS, AERODYNAMICS, OPERATION, and RESEARCH. The compilation is an extension of NACA RM No. L6I13, entitled "Abstracts Pertaining to Seaplanes," by Jerold M. Bidwell and Douglas A. King. An author index and a subject index are included" (p. 1).

"An investigation of the endurance characteristics, at high Mach number, of the J65-W-7 engine was made in an altitude chamber at the Lewis laboratory. The investigation was made to determine whether this engine can be operated at flight conditions of Mach 2 at 35,000-feet altitude (inlet temperature, 250 F) as a limited-service-life engine. Failure of the seventh-stage aluminum compressor blades occurred in both engines tested and was attributed to insufficient strength of the blade fastenings at the elevated temperatures" (p. 1).

Memorandum presenting a theoretical investigation to determine the reasons for poor airplane response to longitudinal control. Some effects of airplane configuration on the response, primarily for short time periods, were also determined. Results regarding a comparison of three airplanes, the effect of changes on airplane B, and the effect of changes on airplane C are provided.

From Introduction: "A theoretical investigation was conducted in order to determine what effect the differences in aerodynamic characteristics would have on the short-time response to elevator control of this type of airplane as compared with the responses of a conventional airplane, without regard to any possible psychological influences. The results of this investigation are presented in this paper."

Report presenting eight thin magnesium fins, seven with the leading edges swept back 17 degrees and one with the leading edge swept back 45 degrees, in the preflight high-temperature jet. The investigation was made to determine the effectiveness of various protective coverings designed to alleviate aerodynamic-heating effects and intended for application on the first stage of rocket-propelled multistage hypersonic models.

Report presenting testing of three uninstrumented tapered magnesium fins with the leading edges swept back 17 degrees in an ethylene-heated high-temperature jet. The testing was carried out to investigate some effects of leading-edge diameter and leading-edge shape on the aerodynamic heating by noting the time for melting to begin on the fins. Results indicated that increasing the diameter of cylindrical leading edge increased the time required for melting to start.

From Summary: "The results of numerous unrelated tests of dive-recovery flaps are collected in this report and presented in a form suitable for use in the preliminary design of dive-recovery flap installations. Since the data were obtained for airplane models of quite widely varying configurations, and are limited largely to a Mach number of 0.80, it is recommended that each new installation be carefully flight-tested before final approval. A flight-test procedure is outlined which will insure a maximum degree of safety."

Report presenting pressure measurements on a semispan model of a cambered and twisted wing, alone and in combination with a fuselage. The wing had 40 degrees of sweepback, an aspect ratio of 10, a taper ratio of 0.4, and 5 degrees of washout at the tip. Results regarding the pressure distribution and flow separation, section characteristics, and span loading characteristics are provided.

Report presenting an investigation in the free-spinning tunnel on a model of the Republic F-105B airplane to determine the spin and recovery characteristics. Results indicated that even with perfect control technique, full movement of the rudder against the spin and of ailerons with the spin is not adequate to ensure satisfactory recovery; extensions of both canard surfaces should accompany the control technique. Results regarding ideal parachute design are also provided.