Memorandum presenting an investigation to evaluate the effect of Reynolds number and Mach number on the aerodynamic characteristics of a horizontal tail of aspect ratio 3 equipped with a plain, sealed, full-span elevator. The line joining the quarter-chord points of the airfoil sections was swept back 45 degrees and the sections perpendicular to this line were the NACA 64A010. Results regarding the effect of Reynolds number and effects of leading-edge roughness and elevator-nose seal are provided.

Wind-tunnel tests of a full-scale model of the Republic XF-91 airplane were conducted to determine the distribution of pressure over the external wing fuel tank installation and over the vee tail and ventral fin. The data were obtained for a range of angles of attack and sideslip and elerudder deflection angles; the presentation is in tabular form.

Report presenting an investigation to study the aerodynamic problems associated with a turbine design for a mode of engine operation which utilizes turbine stator adjustment to maintain a fixed compressor operating point. An indication of the turbine requirements for a particular compressor operating point indicated that a feasible sing-stage air-cooled turbine design could be obtained within reasonable aerodynamic limits. Results regarding the performance of the turbine, pressure ratios, and operational requirements are provided.

Report discussing flow surveys made of several nozzles using two 2-dimensional steps at Mach number 6.98. Results regarding wall-pressure surveys, disturbance patterns in expansion, total-pressure survey, temperature recovery, and general nozzle characteristics are provided.

Report presenting visual observations and flow analyses made of annular liquid flow with cocurrent air flow in 2- and 4-inch-diameter horizontal transparent tubes. The experiments occurred over a range of air mass velocities, air temperatures, and Reynolds numbers. Results regarding the velocity and thickness of liquid films, description of water-film disturbances, effect of flow variables on liquid-film characteristics, and relation between disturbances and flow conditions are provided.

Report presenting an investigation of spoilers at a Mach number of 1.93 to determine the effects of height and chordwise location on the section pressure distributions and section aerodynamic characteristics of a two-dimensional, 6-percent-thick, symmetrical wing. Spoilers of 3-, 5-, and 7-percent-chord height were tested at three chordwise locations. Results regarding pressure distributions, aerodynamic characteristics, and shock boundary-layer interactions are provided.

Memorandum presenting an investigation of a series of five 75S-T6 aluminum-alloy elementary skin and spar-cap combinations with skin varying from 0.051 to 0.500 inch in thickness to determine the temperature and stress gradients resulting from the application of heat to the surface. The data are presented in the form of tables of the measured temperatures and stresses calculated from the measured strains.

Report presenting an investigation in the 4- by 4-foot supersonic pressure tunnel to determine the effects of body indentation on the minimum drag and maximum lift-drag ratio of a 60 degree swept-wing-body combination. A secondary goal of the tests was to determine the effect on the maximum lift-drag ratio of modifying the inboard plan form of the 60 degree swept wing. Lift, drag, and pitching-moment data are presented.

Report presenting an investigation of the low-speed power-on stability and control characteristics of a free-flying model of the North American X-15 airplane. Results regarding the longitudinal stability and control, lateral stability, and lateral control are provided. Longitudinal stability was low, but it was considered to be satisfactory up to an angle of attack of about 30 degrees.

Report presenting an investigation of three axial-flow-compressor inlet stages with a hub-tip diameter ratio of 0.5 to determine whether high pressure ratios can be obtained by means of high turning with highly cambered subsonic types of blading and the effectiveness of radial gradients of energy addition in reducing the deceleration across the rotor tip and thus relieving the effect of high tip loading. Results regarding the overall stage performance, diffusion factor, element performance, and stage discharge flow distribution are provided.

Investigations were conducted to determine effectiveness of refrigerants in increasing thrust of turbojet engines. Mixtures of water an alcohol were injected for a range of total flows up to 2.2 lb/sec. Kerosene was injected into inlets covering a range of injected flows up to approximately 30% of normal engine fuel flow. Injection of 2.0 lb/sec of water alone produced an increase in thrust of 35.8% of rate engine conditions and kerosene produced a negligible increase in thrust. Carbon dioxide increased thrust 23.5 percent.

Memorandum presenting an investigation of the performances of two annular diffuser designs applicable to turbojet afterburner installations to determine the effectiveness of injection and suction boundary-layer controls. Results regarding inlet measurements, flow observations, static-pressure distributions, downstream velocity distributions, and mean performance coefficients are provided.

Memorandum presenting an investigation of two annular diffusers of different conical angles of expansion but constant outer diameters with rotating flow behind a fan. The performance characteristics are determined and the rotational-kinetic-energy effects on the overall energy transformation are observed over a range of inlet mach numbers from 0.1 to 0.44 and angles of flow up to 28 degrees.

Report presenting drag coefficients determined by the accelerometer method for the Bell X-1 airplane with 8-percent-thick wing and 6-percent-thick tail in power-off flight over a range of Mach numbers and lift coefficients. Results regarding the variation of computed lift and drag coefficients, variation of lift coefficient with Mach number, and effect of Mach number on lift-drag ratio are provided.

Report presenting an investigation of a configuration of a body of fineness ratio 16.9, an unswept wing of aspect ratio 3, and a taper ratio of 0.4, and incline tail surfaces who was aeropulsed continuously in pitch during free flight with and without a sustainer rocket motor operating. A range of Mach numbers from 0.8 to 2.1 was tested. Results regarding drag, normal force and pitching moment, flow conditions at the horizontal tail, buffeting and model vibrations, and cross coupling are provided.

Report presenting lift, drag, and pitching-moment coefficients, lift-drag ratios, and center-of-pressure positions for four airplane-like configurations determined from tests at a range of Mach numbers and angles of attack. The wings and nose shapes were modified for each of the configurations.

Report presenting limited flight measurements made in order to investigate the effect of dynamic vibration absorbers on the structural response of a Lockheed F-80A airplane during buffeting. The results were obtained by comparison of data with and without the absorbers operating through use of electrical frequency-analysis techniques.

Memorandum presenting a systematic study to determine the effect of molecular structure on the flammability limits of pure hydrocarbon-air mixtures at reduced pressures and room temperature. This report presents results obtained for 17 pure normal paraffins, branched paraffins, and mono-olefins. Results regarding experimental variables and experimental observations are provided.

Memorandum presenting a low-speed wind-tunnel investigation conducted to study the effects of pylon-mounted wing tanks and speed brakes on the static stability characteristics of a model with sweptback wing and tail surfaces. The wing of the model was of aspect ratio 3.45 and was swept 40 degrees at the quarter-chord line. Results for the basic configuration and modifications to the basic configuration are provided.

"An investigation was made to determine the static lateral stability and control characteristics of a 1/6-scale model of the Republic XF-84H airplane with the propeller operating. The model had a 40 degree swept wing of aspect ratio 3.45 and had a thin 3-blade supersonic-type propeller. Many modifications to the basic configuration were investigated in attempts to alleviate lateral and directional trim problems which appeared to be associated with propeller slipstream rotation" (p. 1).

From Summary: "The aerodynamic characteristics in pitch of an F-94C airplane, with the primary attention given to its drag characteristics, have been evaluated at low speed in the Ames 40- by 80-foot wind tunnel. The increments of drag due to various surface irregularities, ports, and component parts of the production airplane were determined. Wing-wake surveys were taken to determine the section drag coefficients at midsemispan for the smooth and the production wing. Base-pressure and internal drags of the air-induction system were measured at low inlet-velocity ratios. The characteristics of the airplane in the landing configuration are also included."

Report presenting measurements of average heat-transfer and friction coefficients obtained with air flowing through electrically heated ducts with square, rectangular, and triangular cross sections for a range of surface temperatures and Reynolds numbers. Results regarding heat balances, correlation of heat-transfer coefficients, correlation of friction coefficients, and correlation of peripheral temperature variations are provided.

Report of testing on an untapered 35-degree sweptback airfoil-flap model, representative of a wing or tail surface, with several 1/4-chord full-span flaps differing in aerodynamic balance. A plain flap, a horn-balanced flap, and a beveled-trailing-edge flap were compared to a flap that had a 31-percent-flap-chord overhang balance. Information about lift, pitching-moment, and hinge-moment characteristics is provided.

"Model investigations were made to determine the ditching characteristics of three typical multiengine airplanes equipped with possible arrangements of hydro-ski ditching gear. The behavior of the models was determined from visual observations, acceleration records, and motion pictures of the landings. Data are presented in tabular form and sequence photographs" (p. 1).