Note presenting an investigation of the relationships between conditions of hot-working and properties at high temperatures and the influence of the hot-working on response to heat treatment for an alloy containing nominally 20 percent chromium, 20 percent nickel, 20 percent cobalt, 3 percent molybdenum, 2 percent tungsten, and 1 percent columbium.

"Tests utilizing the schileren method of flow photography have been conducted to provide a comparison of the complete flow fields past an unswept- and a swept-wing-body combination and the flow fields past their equivalent bodies of revolution at Mach numbers around 1.0. The results indicated that the shock growth and positions on the wing-body combinations were closely reproduced in the flow past the equivalent body" (p. 1).

Note presenting an analysis of the low-speed wake characteristics of two-dimensional cascade and isolated airfoil sections based on available experimental data and supplementary theory. Empirical and theoretical variations with downstream distance of such wake properties as minimum velocity, form factor, momentum thickness, full thickness, and total-pressure loss are presented. The analysis indicates a general similarity between turbulent cascade and isolated airfoil wake characteristics.

Report presenting the problem of the three-point body of revolution that has minimum wave drag, based on linearized supersonic-flow theory, which has been solved formally without resorting to slender-body approximations. The evaluation of the source-distribution function, as well as body shape, requires numerical procedures.

Report presenting an investigation in the 300 mph 7- by 10-foot tunnel and gust tunnel to determine the static longitudinal aerodynamic characteristics an the gust-alleviation capabilities of forward-located fixed spoilers, deflectors, or a spoiler-deflector combination on a simulated transport airplane model with an unswept wing. Results regarding the static/force test, dynamic/gust-tunnel test, and short-period frequency and damping are provided.

Note presenting an investigation of the slip-line structure in a series of aluminum single crystals deformed in tension in an electron microscope. In several of the crystals, the slip-line structure was examined after successive steps in the elongation.

Note presenting a program to investigate the aerodynamic heat transfer of a non-isothermal hemisphere-cylinder in the 11-inch hypersonic tunnel at a Mach number of 6.8. Results regarding pressure distribution, laminar recovery factor, temperature distribution, heat-transfer parameters, average heat-transfer coefficient, and schileren observations.

Report presenting three experimental investigation conducted with 75-millimeter-bore cylindrical roller bearings to determine the effects of roller axial clearance ratio, cage diametral clearance ratio, and cage land width-diameter ratio on bearing operating temperatures, wear, cage slip, and high-speed operating characteristics.

Report presenting turbulent-heat-transfer measurements obtained through the use of an axially symmetric annual nozzle consisting of an inner shaped center body and an outer cylindrical sleeve at Mach number 3.90. Results regarding the variation of wall temperature with longitudinal distance, variation of local Nusselt number with local Reynolds number, and variation of local temperature-recovery factor with local Reynolds number are provided.

Report presenting pressure distributions and force characteristics for a body of revolution consisting of a fineness ratio of 5.75, circular-arc, ogival nose tangent to a cylindrical afterbody for a range of angles of attack. Comparison of the theoretical and experimental pressure distributions shows that for zero lift, both slender-body theory and higher-order theories yield results that are in good agreement with theory.

Twenty-five ring-stiffened circular cylinders were loaded to failure in bending. The results are presented in the form of design curves which are applicable to cylinders with heavy rings that fail as a result of local buckling.

Effects of Reynolds number and angle of attack on the pressure distribution and normal-force characteristics of a body of revolution consisting of a fineness ratio 3 ogival nose tangent to a cylindrical afterbody 7 diameters long have been determined. The test Mach number was 1.98 and the angle-of-attack range from 0 degree to 20 degrees. The Reynolds numbers, based on body diameter, were 0.15 x 10(6) and 0.45 x 10(6). The experimental results are compared with theory.

Report presenting an investigation at speeds of up to Mach number 0.90 to determine the effects of operating propellers on the longitudinal characteristics of a four-engine tractor airplane configuration with a 40 degree swept wing with an aspect ratio of 10. Results regarding low-speed conditions, high-speed conditions, components of lift, effect of configuration changes, longitudinal stability, and the reduction of adverse effects of propellers on stability are provided.

Note presenting a semiempirical method for the calculation of the sound field about a source over ground considering the effects of vertical temperature and wind gradients as well as scattering of sound by turbulence into shadow zones. The two adjustable parameters in the formula were obtained from measurements suing a relatively small source height.

Report presenting the derivation of the integral equations for transonic flow around slender wings and bodies of revolution, with special attention paid to conditions resulting from the presence of shock waves and to the reduction of the relations to the special forms necessary for the discussion of sonic flow.

Formulas for the wave drag of shrouded symmetrical airfoils and shrouded bodies of revolution of arbitrary shape are derived by means of linearized theory. In the case of the airfoils, the shroud consists of flat plates and for the bodies of revolution the shroud is a cylindrical shell. The results obtained hold for a Mach number range dependent on the geometry of the configuration. Expressions are also given for determining a class of body shapes for which the wave drag is theoretically zero.

From Summary :"Measurements of Poisson's ratios have been made in three orthogonal directions on aluminum alloy blocks in compression and on stainless-steel sheet in both tension and compression. These measurements, as well as those obtained by density determinations, show that there is no permanent plastic change in volume within the accuracy of observation. A method is suggested whereby a correlation may be effected between the measured individual values of the Poisson's ratios and the stress-strain curves for the material."

"By means of examples, a new method is illustrated for optimizing, over a finite interval of time, time-varying systems with stationary or nonstationary statistical inputs. The method depends on the correlation functions being of a certain type, which, fortunately, is the type found in a large number of practical problems of importance" (p. 1).

Report presenting a treatment of several problems on the large deflections of curved plates with compound curvature. Testing demonstrated that the effective width of the curved plates in longitudinal compression is reduced by the presence of an initial deflection function.

Report presenting the paths of cloud droplets into two engine inlets for a wide range of meteorological and flight conditions. The amount of water in droplet form ingested by the inlets and the amount and distribution of water impinging on the inlet walls is obtained from droplet-trajectory configurations. Results regarding an inlet with velocity ratio of 1.0 and a ratio of 0.7 are provided.

Report presenting fatigue testing in rotating bending on severely notched bars machined from 2024-T4 aluminum-alloy extruded round rods. Two sizes of specimens were studied.

Report presenting an investigation to determine the transition Reynolds numbers on a 10 degree cone in the 4- by 4-foot supersonic pressure tunnel at three Mach numbers and a range of Reynolds numbers. Results regarding a smooth cone and a cone with roughness are provided.

"Experimental results of lifts and moments about the quarter chord of a two-dimensional wing at subsonic Mach numbers are presented. A comparison of the experimental magnitude of the lift vector with the theory as given by Dietze showed good agreement. Comparisons of the moments and the quadrature component of lift with theory indicated that some refinements in the testing technique are necessary for the experimental determination of these quantities in the transonic range" (p. 1).

Note presenting results of tensile and bend tests on specimens in the T6 condition from 12- by 12- by 24-inch hand forgings of 7075 (75S) and 2014 (14S) aluminum alloy. Thirty-six notched bend specimens were tested as cantilever beams together with 48 tensile specimens of material adjacent to the bend specimens. Marked differences were found in the results of tensile tests on specimens in different directions and from different locations in the billet.