Report presenting an investigation of the performance of a diffuser static-pressure-ratio control with a normal shock-positioning limit on a ramjet engine installed in an altitude free-jet facility. Testing occurred at Mach numbers of 2.35 and 2.50, altitudes of 50,000, 60,000 and 65,000 feet, and angles of attack of 0 and 7 degrees. Results regarding the effects of control constants, effects of disturbance size and operating point, effects of flight conditions, and control limitations and possible improvements are provided.

Injection techniques for fluorine, oxygen, and heptane in 200-pound thrust rocket engine.

"A 1/13-scale model of the forebody of the Republic F-105 with twin-duct wing-root inlets was tested in the Langley 4- by 4-foot supersonic pressure tunnel through a range of angle of attack from -4 deg to 15 deg at a Mach number of 2.01 and a Reynolds number of approximately 3.4 x 10(exp 6) per foot. The tests were made with four configurations which incorporated varying amounts of sweep and stagger of the inlet leading edges, modifications to the areas of the boundary-layer diverter floor plate, and modifications to the area of the boundary-layer diverter bleed slots. The highest overall pressure recovery at an angle of attack of 0 deg (average total-pressure recovery, 0.84 mass-flow ratio, 0.98) was achieved with configuration having an inlet leading-edge sweep angle of 58 deg with no leading-edge stagger" (p. 1).

Report presenting static tests on the compatibility of gaseous fluorine with various liquids, solid plastics, waxes, and greases at pressures of 0 and 1500 pounds per square inch gage and atmospheric temperature. Several materials were found to be compatible at atmospheric pressure, but only Teflon and ruby were compatible under static conditions at 1500 pounds per square inch gage.

Memorandum presenting an investigation to determine the drag, longitudinal stability, and lateral stability characteristics of a model of a fighter-type airplane. Several modifications were made to the model in an attempt to eliminate pitch-up.

Memorandum presenting forces and moments measured at Mach number 1.6 in the 4- by 4-foot supersonic pressure tunnel on bombs of fineness ratios 7.0 and 10.5 in the presence of a swept-wing fighter-bomber airplane configuration for a large number of positions under the fuselage. The results can be used to calculate bomb-drop paths.

"Pressure-distribution and force tests of a circular cylinder have been made in the Langley 11-inch hypersonic tunnel at a Mach number of 6.88, a Reynolds number of 129,000, and angles of attack up to 90 degrees. The results are compared with the hypersonic approximation of Grimminger, Williams, and Young and a simple modification of the Newtonian flow theory. An evaluation of the crossflow theory is made through comparison of present results with available crossflow Mach number drag coefficients" (p. 1).

Note presenting flight investigations of single-axis attitude stabilization during low-speed instrument approaches. A single-rotor helicopter that had been modified to include an electronic control system was used in the investigation. Results regarding heading stabilization, pitch stabilization, and roll stabilization are provided.

"The similarity rules for linearized compressible flow theory (Göthert's rule and its supersonic counterpart) are extended to second order. It is shown that any second-order subsonic flow can be related to "nearly incompressible" flow past the same body, which can be calculated by the Janzen-Rayleigh method" (p. 1).

From Introduction: "In order to provide engine-inlet matching to prevent such mass flow spillage and the attendant drags, much mechanical complication has been introduced. References 1 and 2 propose employing this principle at subsonic and supersonic speeds to achieve thrust augmentation. The merits of the system for supersonic engine-inlet airflow matching, as well as thrust augmentation, appear considerable; and a comparative study with existing fixed- and variable-geometry inlets was therefore undertaken."

Results are presented of an investigation of the effectiveness of a wing equipped with a 50-percent-chord sliding flap and a 30-percent-chord slotted flap in deflecting a propeller slipstream downward for vertical take-off. Tests were conducted at zero forward speed in a large room and included the effects of flap deflection, proximity to the ground, a leading-edge slat, and end plates. A turning angle of about 70 degrees and a resultant force of about 100 percent of the thrust were achieved near the ground. Out of the ground-effect region, the turning angle was also about 70 degrees but the resultant force was reduced to about 86 percent of the thrust.

A missile research model was flown at supersonic speed to determine the quality of automatic roll stabilization at varying angles of attack. Aerodynamic rolling and pitching derivatives were determined from the flight record. It was concluded that the combination of the gyro-actuated automatic pilot with wing-tip ailerons provided adequate roll stabilization under conditions encountered in flight.

Note presenting an investigation to determine the effect of propeller location and flap deflection on the lift, drag, and pitching-moment characteristics of a wing-propeller combination over a range of angles of attack. The model had four propellers, the slipstream from which covered practically the entire span of the wing. The results indicated that power factors exist for changing the variation of pitching moment with speed.

Report presenting approximate solutions describing mainstream flows confined to regions of small angle variation over flat surfaces for three-dimensional, laminar, incompressible, thin boundary-layer flows with similar with respect to stationary polar coordinate systems. Results regarding the mainstream, boundary layer, ordinary differential equations, and comparison with experiment are provided.

Report presenting eleven 110-millimeter-bore ball thrust bearings made of M-1 tool steel were operated over a range of DN values at mean outer-race temperatures to 678 degrees Fahrenheit. Testing occurred at a variety of thrust loads, radial loads, oil flows, and oil inlet temperatures. Results regarding the difference between tests without heat addition and tests with heat addition, fatigue failures, performance of cage materials, and oil-interruption tests are provided.

Report presenting a discussion of the basic theory of pneumatic temperature probes and deviations from the basic theory in practical applications. Design requirements and operating conditions are discussed. Results regarding calibration tests and high-temperature tests and results are provided.

Note presenting oblique-shock relations for air in chemical equilibrium, which have been calculated for flight velocities up to 25,000 feet per second at altitudes up to 200,000 feet. The variation of flow-deflection angle with shock angle differs significantly from that of an ideal gas. Results regarding normal-velocity ratio, flow deflection across shock, Mach number behind shock, mass-flow ratio, temperature, entropy increase, and other parameters are provided.

Report presenting an investigation of several ways of simultaneously simulating the external pressure field generated by an engine exhaust jet and an air inlet. The results indicated that the pressure field in the vicinity of the exit station and external to a real exhaust jet could be adequately simulated while keeping the inlet at critical or supercritical mass flow. Results for a target probe, a perforated probe, and the pressure and airflow required in the probes are provided.

Note presenting an investigation to determine the Reynolds and Mach number effects on the base pressure of a nonlifting ogival body of revolution over the Reynolds number range in which wake transition occurs. The results were compared with previous base-pressure data and also with the qualitative theoretical predictions of Crocco and Lees.

A method for calculating the aerodynamic loading on a wing in combination with a body is presented. Calculated results are compared with experimentally measured data for two wing-body configurations throughout a range of Mach number up to 1.0. The magnitude and the distribution of spanwise loading of the calculated data are generally in good agreement with the experimental data.

From Introduction: "In the present paper, the emphasis is placed on calculating the variations of total forces and moments with angles of attack and sideslip for a number of slender plane and cruciform wing-tail combinations and for some airplane-type arrangements of a plane wing and a horizontal and vertical tail."

Report presenting an analysis of the effect of ambient temperature on the matching requirements of inlet-engine combinations for two typical turbojet engines up to Mach number 3.5. The results indicated that if a bypass or movable compression surface are to be used for efficient inlet-engine matching, the inlet should be sized for the lowest ambient temperature to be encountered.

Report presenting testing to determine the properties of several untreated commercial cotton-fabric pheonlic sheet laminates, the same sheets after exposure to a postforming heating cycle, industrially postformed shapes made from those materials, industrially molded and laboratory-molded shapes, and flat panels postformed in the laboratory from the laboratory-molded shapes. Results regarding tensile properties, flexural properties, and water absorption are provided.

Note presenting an investigation to determine the effects of composition and homogenization heat treatments on the hardness and tensile properties of cast alloys of the NiAl intermetallic phase. The phase exists over a wide range of composition with stoichiometric NiAl at 31.5 percent aluminum. Results regarding the effects of the casting method and mechanical properties of the homogenized NiAl phase are provided.