"An approximate method for the development of flow and thermal boundary layers in the laminar region on cylinders with arbitrary cross section and transpiration-cooled walls is obtained by the use of Karman's integrated momentum equation and an analogous heat-flow equation. Incompressible flow with constant property values throughout the boundary layer is assumed. The velocity and temperature profiles within the boundary layer are approximated by expressions composed of trigonometric functions" (p. 339).

Report presenting an investigation to gain information concerning the durability of metallic coatings as affected by frit content, firing temperature, firing time, and number of coats. Four coatings of various frit content were prepared and applied to ceramals containing 80 percent chromium and 20 percent cobalt and heated at four different temperatures.

Note presenting a wind-tunnel investigation to determine the effects of jet-outlet cut-off angle on the directional and spreading characteristics of an unheated, subsonic air jet, and on the pitching moment of the body from which the jet issued. Results regarding the jet operating with the wind tunnel off, jet off with the wind tunnel operating, jet operating with the wind tunnel operating, and flow studies with the jet operating and the wind tunnel off are provided.

Report presenting practical methods for making the calculations required for the analysis of an autopilot and an autopilot-aircraft combination from frequency-response data. From Summary: "Equations are derived for determining the servo-system error voltage for both displacement input signal and displacement plus rate of displacement input signals, the autopilot frequency response for addition of rate of displacement input signal, the servo-system frequency response for a change of gain, and the relation between open-loop and closed-loop frequency responses for the servo system and the autopilot-aircraft combination."

Report presenting a method utilizing precalculated solutions graphically presented for calculating subsonic or supersonic ramjet performance parameters with the associated equations and graphs. By assuming constant values of specific-heat ratio and gas constant equal to those of standard air, the thrust-coefficient calculation has been reduced to a few simple operations.

Note presenting testing to determine whether lead compounds in the combustion products of high-octane fuel are a contributing factor in causing failures of the heat-resistant alloy parts in aircraft exhaust systems. To obtain answers for five heat-resistant alloys, a test was devised in which the alloy specimens in an uncoated condition, in a preoxidized condition, and with three different ceramic coatings were exposed for 6 hours to lead-containing vapors in an air atmosphere at 3 different temperatures.

Report presenting the results of axial-load fatigue tests on notched specimens of three sheet materials: 24S-T3 and 75S-T6 aluminum alloys and SAE 4130 steel. Fatigue tests were run at several levels of nominal mean stress, including a zero nominal mean stress. Fatigue tests for notched specimens are compared with previously reported unnotched specimens of the same materials.

From Summary: "This reports presents of axial-load fatigue tests on notched specimens of three sheet materials: 24S-T3 and 75S-T6 aluminum alloys and normalized SAE 4130 steel. Each specimen was notched by edge notches designed to have a theoretical stress-concentration factor of 5.0. Tests were run at four levels of nominal mean, stress: 0, 10,000, 20,000, and 30,000 psi. Results of these tests extend information previously reported from tests on unnotched specimens and on specimens less severely notched."

From Summary: "The hydrocarbons - 2-cyclopropyl-1-butene, cis and trans 2-cyclopropyl-2-butene, and 2-cyclopropylbutane - were obtained from methylcyclopropyl ketone by reacting the ketone with ethylmagnesium bromide, dehydrating the resultant methylethylcyclopropylcarbinol to a mixture of olefins from which 2-cyclopropyl-1-butene and cis and trans 2-cyclopropyl-2-butene were isolated, and hydrogenating the olefins to 2-cyclopropylbutane. All four hydrocarbons were obtained in high purity for the first time; their physical constants and infrared spectra are presented."

Report presenting an investigation of the significance of tensile strength and ductility in the presence of defects and the strength-reducing effects of several types of defect were investigated for some rotating disks. Some of the defects investigated included laminar-type irregularities, eutectic melting, and shrink porosity.

Note presenting calculations of the ratios of the velocity increments at test bodies to those at the tunnel walls caused by the solid blocking of these bodies within the walls of a closed rectangular wind tunnel. The bodies treated include two-dimensional airfoils, small bodies of revolution, straight, untapered, finite-span wings of varying span, and swept, untapered, finite-span wings of varying span.

Report presenting an investigation of the flutter characteristics of a uniform, unswept, cantilever wing of high aspect ratio and under conditions of high mass coupling by means of a Rayleigh type analysis based on coupled modal functions. Results are compared with an experiment and the calculated results of NACA TN 1902.

"An analytical method based on successive approximations is presented for determining the loads and deflections throughout an indeterminate structure in which one or more of the members have been stressed beyond their proportional limits. Theoretical analyses of three structures are compared with tests and found to agree very closely. For the sake of simplicity and clarity, only coplanar pin-ended structures have been analyzed and tested" (p. 1).

Report presenting the effects of cyclic and continuous immersion in heptane, toluene, and SR-6, a test fuel, on the weight, dimensions, and flexural properties of 19 samples of laminated plastics. No one sample exhibited smaller changes than all other samples in all properties for all fuels and for both cyclic and continuous immersion. Results regarding weight and dimensional changes and changes in flexural properties are provided.

Report presenting an analytic method for the design of automatic controls that has been developed and starts from arbitrary criterions on the behavior of the controlled system and gives those physically realizable equations that the control system can follow in order to realize the behavior. The criterions used are developed in the form of certain time integrals. General results are shown for systems of second order and of any number of degrees of freedom.

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 results and analysis of the longitudinal stability and control characteristics of the Douglas D-558-I airplane at a range of altitudes and Mach numbers. It was found that large and rapid changes in elevator deflection and force were required for balance at Mach numbers above 0.84 due to a sharp decrease in elevator-stabilizer effectiveness.

Report presenting an investigation of some effects of aileron spanwise location and wing structural rigidity on the rolling power of 0.3-chord plain, flap-type ailerons on a wing with a taper ratio of 0.25, an aspect ratio of 3.5, and swept back 63 degrees at the leading edge. Results regarding the aeroelastic effects and aileron span and spanwise location are provided.

Memorandum presenting an NACA submerged inlet and an NACA series I nose inlet installed in bodies of 12.4 fineness ratio to determine the drag and pressure-recovery characteristics of each body-inlet configuration. The tests were conducted with large-scale free-fall models released at an altitude of 40,000 feet, for mass-flow ratios of about 0.4 and 0.7 over a Mach number range of about 0.70 to 1.10. Results regarding drag and ram-recovery ratios are provided.

"A simple apparatus particularly applicable to the determination of the corrosive effects of flowing liquid metals on structural materials is described. In this apparatus, flow of the liquid medium at known velocities may be induced in toroidal shaped channels fabricated from the test structural material only, with no pump, valves, or flow meter required. A circulating velocity of 25 ft/sec has been obtained in preliminary tests and no basic limitation on increasing the speed was encountered" (p. 1).

Memorandum presenting a study of the effect of prestrain in tension upon the stress-strain characteristics in compression for copper and brass. The residual stress phenomenon known as the Bauschinger effect is of primary importance in cyclic loading, inasmuch as it serves to reduce the yield strength of plastically strained metal to deformation of the opposite sign.

Report discussing an investigation of the effect of sweepback angle on wing-fuselage characteristics at a subsonic and a supersonic Mach number. Lift, drag, and pitching-moment coefficients, downwash-angle, and total-pressure measurements are all provided.

This report presents the results of an investigation to ascertain the lift, drag, and pitching moment of a wing-body combination having a triangular wing of aspect ratio 2 with NACA 0003-63 thickness distribution in streamwise planes and twisted and cambered for a nearly elliptical span load distribution. Results are shown for Mach numbers from 0.60 to 0.90 and from 1.30 to 1.70 at Reynolds numbers of 3.0 million and 7.5 million.

Report presenting design features for the instrumentation used in a study of the transient performance of gas-turbine engines and control systems. The dynamic characteristics of the instrumentation are discussed and examples of typical acceleration data for a controlled and an uncontrolled engine are provided.