"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.

From Summary: "An analysis has been made of available experimental data to show the effects of most of the variables that are more predominant in determining base pressure at supersonic speeds. The analysis covers base pressures for two-dimensional airfoils and for bodies of revolution with and without stabilizing fins and is restricted to turbulent boundary layers. The present status of available experimental information is summarized as are the existing methods for predicting base pressure."

Note presenting an investigation of the rotating-stall characteristics of a single-stage axial-flow compressor. The number of stall cells and their propagation velocities were found with and without stator blades. Results regarding steady-state characteristics, stall characteristics with stator blades, stall characteristics without stator blades, a comparison of actual and predicted propagation velocities, and pressure fluctuations are provided.

Report presenting an investigation to determine the combined effects of nose blunting and cooling on boundary-layer transition. Data are presented for both sharp and blunted cone-cylinder and parabolic-nosed - cylinder bodies at a variety of Reynolds numbers. Results regarding the cone-cylinder model, parabolic-cylinder model, and transition reversal are provided.

"The results of 55 creep and creep-rupture tests on structural joints are presented. Methods are described by which the time to rupture, the mode of rupture, and the deformation of joints in creep may be predicted. These methods utilize creep data on the materials of the joint in tension, bearing, and shear" (p. 1).

Report presenting a determination of the effect of rotor forward speed on the propulsive characteristics of a blade-tip-mounted helicopter-type pulse-jet engine in the full-scale tunnel for various engine rotational speeds. The effect of forward speed was to decrease mean engine thrust and increase engine specific fuel consumption. Results regarding power-off engine drag, power-on engine thrust characteristics, and a general engine performance summary are provided.

Report presenting comparisons of experimental and calculated pressure losses for Newtonian non-Newtonian materials. The transition loss coefficients obtained for the Newtonian and non-Newtonian materials and those reported in the literature for Newtonian fluids agree within the errors of experiment.