"This report presents results of a research and engineering program performed during the first half of 1950 that resulted in an acoustical treatment for the 8- by 6-foot supersonic wind tunnel at the Lewis Flight Propulsion Laboratory" (p. 1).

Report presenting the use of the shock-expansion method for the calculation of the pressure distribution on cylindrical wings in supersonic flow as extended to tapered wings made up of single-curved surfaces. The method applies in regions of the wing where the component of velocity normal to the surface rulings is supersonic and the flow is not influenced by the presence of the root or tip.

Note presenting a description of equipment and test technique used in the creep testing of lap joints. Riveted aluminum-alloy joints fabricated from 75S-T6 and 24S-T3 sheet with 24S and 24S-T31 rivets were tested at 300, 400, and 500 degrees Fahrenheit. The test results showed that the creep of the riveted joints is considerably greater than the creep of the unriveted sheet although not so large that the creep of the sheet is negligible compared with that of the joints.

Report presenting measurements of lift made on various rectangular-plan-form wings differing in trailing-edge thickness, profile shape, maximum thickness ratio, and aspect ratio. Experiments were conducted at a range of Mach numbers, Reynolds numbers, and wings with and without boundary-layer trips. Results regarding a comparison of experimental results with theory at moderate supersonic Mach numbers and calculations for hypersonic Mach numbers are provided.

"The effects of lip thickness on inlet performance are estimated as functions of mass flow for subsonic and supersonic flight speeds. At subsonic speeds, pressure-recovery losses and additive drag are shown to decrease linearly with increasing lip frontal area if the maximum suction force is attained. At supersonic speeds, inlet drag increases linearly with inlet lip frontal area at full mass flow. For reduced mass flow, some reduction in additive drag is possible with lips of moderate thickness, but the magnitude of this reduction becomes negligible as flight speed increases" (p. 1).

"Two straight mineral oils and a polymer-containing oil have been tested in a rotating-cylinder viscometer at high shear rates (maximum 0.25 million reciprocal seconds) and the accompanying heat effects have been investigated. The torque measurements are of low accuracy and fail to establish the moderately non-Newtonian behavior of the polymer-containing oil, but the temperature measurements, which are in good agreement with a thermal analysis, do indicate the presence of temporary viscosity decrease at high shear rates for this oil" (p. 1).

Note presenting the solutions corresponding to the reflection of a centered simple wave along a straight wall and along a free streamline of constant pressure in mathematical terms and expressed in terms of a Fourier transform. The solutions are found to be simply reflated to some important solutions arising in the theory of linear partial differential equations.

Note presenting the approximate formula of a linearized solution for the pressure field generated by a moderate rate of heat release. The analogies between the pressure waves generated by heat release and those generated by (1) mass release, (2) piston motion, or (3) a two-dimensional body in a supersonic stream are established analytically.

"Values of coefficients for defining the effectiveness of integral stiffeners in resisting shear deformations of the plate of which they are an integral part are presented for a variety of proportions of rectangular stiffeners with circular fillets. Formulas are given in which these coefficients may be employed to calculate the elastic constants associated with the twisting and shearing of integrally stiffened plates. The size of fillet radius is shown to contribute appreciably to the degree of penetration of the stresses from the skin into the stiffener" (p. 1).

Note presenting a Rayleigh energy approach utilizing the bending mode of the nonrotating beam in the determination of the bending frequency of the rotating beam, which is evaluated and is found to give good practical results for helicopter blades. Charts are presented for the rapid estimation of the first three bending frequencies for rotating and nonrotating cantilever and hinged beams.

From Summary: "A method for the solution of the incompressible, nonviscous flow through a centrifugal impeller, including the inlet region, is presented. Several numerical solutions are obtained for four weight flows through an impeller at one operating speed. The results are presented in a series of figures showing streamlines and relative velocity contours."

Report presenting the detailed solution of the flow around the blade nose of a 48-inch-diameter radial-inlet centrifugal impeller obtained by relaxation methods for four weight flows. The results are presented in a series of figures showing streamlines and relative velocity contours.

Report presenting an investigation to determine the aerodynamic characteristics of a series of thin, rectangular wings utilizing the transonic bump technique. Testing occurred over a range of Mach and Reynolds numbers. Lift, drag, and pitching-moment data are presented for wings of 7 different aspect ratios and NACA 63A0XX sections with 5 different thickness-to-chord ratios.

Report presenting an investigation to determine the effects of camber on the aerodynamic characteristics of a series of rectangular wings with various aspect ratios and thickness-to-chord ratios using the transonic bump method. Testing occurred over a range of Mach and Reynolds numbers. Lift, drag, and pitching moment data are presented for wings of 5 aspect ratios, NACA 63A2XX and 63A4XX sections, and 5 thickness-to-chord ratios.

Report presenting turbulent-heat-transfer measurements obtained through the use of an axially symmetric annular nozzle consisting of an inner, shaped center body and an outer cylindrical sleeve for a Mach number of 1.62. Results regarding wall temperatures, variation of local Nusselt number with local Reynolds number, density, viscosity, and variation of local temperature-recovery factor with local Reynolds number are provided.