Report presenting a measurement of the magnitudes of pressure fluctuations in the turbulent wakes of restrained two-dimensional airfoils at transonic speeds. Measurements indicated that the total-pressure fluctuations occurred only within the wake. Results regarding the magnitude of pressure oscillation in the wake, effect stream-angle fluctuations in the wake, and frequencies of pressure oscillation on the wing and in the wake are provided.

Report presenting base pressures measured on several fin-stabilized bodies of parabolic-arc profile in free flight at a range of Mach and Reynolds numbers. The bodies varied in length but had the same afterbody ratios. Results regarding base pressure coefficients, side pressure coefficients, effect of afterbody length, and drag are provided.

A set of modified NACA 65-series blower blades designed for axial inlet velocity, high inlet Mach number, and high blade loading was investigated for trailing-edge thickness of 0.015, 0.030, and 0.045 inch to determine the effect of trailing-edge thickness on single-stage axial-flow-compressor performance. Trailing-edge thickness effects were small except at the highest tip speed investigated (915 ft/sec). Trailing-edge thickness up to 30 percent of maximum blade thickness were used without sacrifice of performance of NACA 65-series blades.

Memorandum presenting results obtained during Air Force testing of the Northrop X-4 airplane. Information is included on the stalling characteristics, the static and dynamic longitudinal and lateral-stability characteristics, and the lateral-control characteristics.

Report presenting a study of the pressure-drag reduction obtained by projecting a high-energy jet of air from the nose of a prolate spheroid at transonic speeds. Results regarding the pressure distribution on the body, pressure drag, shadowgraphs, and some notes regarding the slope of the body and level of shear at the jet exit are provided.

The altitude-ignition limits of a condenser-discharge ignition system installed on a turbojet engine were determined at a flight Mach number of 0.6 using 1.1-pound Reid vapor pressure fuel. Ignition was possible up to an altitude of 55,000 feet with 4.8 joules per spark and 6 sparks per second.

Memorandum presenting the results of an experimental investigation to determine the effects of Reynolds number on the flow characteristics over a delta wing at a Mach number 2.41. The wing streamwise airfoil sections are based on the NACA 00-thickness series with the maximum thickness varying from 4 percent at the root section to 6.24 percent at the 90-percent spanwise station. Results regarding force data and pressure-distribution data are provided.

Testing occurred using the NACA wing-flow method at a range of Mach numbers to determine the effect on aerodynamic characteristics of reversing a triangular wing with a 6-percent-thick biconvex section. Results regarding the lift characteristics, drag characteristics, and pitching-moment characteristics are provided.

Report presenting the low-speed lateral control and hinge-moment characteristics of a 20-percent-chord plain aileron on a 47.7 degree sweptback wing of aspect ratio 5.1 in the pressure tunnel. The tests were performed with and without high-lift and stall-control devices. Results regarding the basic aileron data, rolling-moment characteristics, and pitching-moment characteristics are also provided.

Report presenting an investigation of the longitudinal characteristics of a wing with 45 degree sweepback of the quarter-chord line, an aspect ratio of 8, a taper ratio of 0.45, and NACA 63(sub)1A012 airfoil sections. The results were obtained from force measurements and distribution measurements for a range of Reynolds numbers. Information regarding lift and pitching-moment characteristics, drag characteristics, and loading characteristics is provided.

An experimental investigation of a highly loaded two-stage turbine with a downstream stator revealed that (1) at equivalent design work and speed the brake internal efficiency was 0.81 and the maximum efficiency obtained was 0.85, and (2) the downstream stator left very little energy in the form of tangential velocity in the gas and, in general, performed well with 0.78 recovery being obtained at equivalent design work and speed.

Report presenting a large wind tunnel that has been converted to transonic operation by means of slots in the boundary extending in the direction of flow. The usefulness of a slotted wind tunnel has been augmented by devising a slot shape with which a supersonic test region with excellent flow quality can be produced.

An air-cooled turbine blade with a capped leading edge was investigated in a modified commercial turbojet engine over a range of engine speed from 4000 to 11,350 rpm. The cooling performance of the caped-leading-edge configuration was superior to all leading-edge cooling modifications previously investigated.

Fundamental flame velocities are reported for pentane air, ethylene-air, and propylene-air mixtures for the concentration range 60 to 130 percent of stoichiometric. A form of the Tanford and Pease equation, which includes a small constant velocity term independent of diffusion, will predict the observed changes in flame velocity.

"An analytical investigation was made of the performance of isolated ram-jet engines in the flight Mach number range from 3 to 7 for two types of diffuser, a high-efficiency diffuser, and a normal-shock diffuser. The fuel was assumed to be a hydrocarbon similar to gasoline. The conclusions reached are: (1) a design altitude of about 100,000 feet is desirable for a high-efficiency high Mach number ram jet on the basis of engine construction and performance; and (2) although greater thrust could be obtained with other fuels, gasoline provides sufficient energy release for maximum engine efficiency in the flight Mach number range investigated. The maximum engine efficiency calculated was 0.47, which occurred at a Mach number of 5. At a Mach number of 7, the maximum propulsive-thrust coefficient was 0.57" (p. 1).

Report presenting an investigation of combined compressor coolant injection and tailpipe burning as a means of turbojet engine thrust augmentation at sea-level, zero ram conditions on a 4000 pound thrust, axial-flow-type turbojet engine. Water-alcohol injection flows from 2 to 5 pounds per second were introduced into the compressor in conjunction with tail-pipe burner fuel-air ratios from 0.017 to stoichiometric. Results regarding engine performance and operational characteristics are provided.

Preliminary investigation was made of conical cooling air ejector at primary pressure ratios from 1 to 10. The cooling-air flow was maintained at zero and the resulting pressure variation in the shroud indicated pumping ability. The cooling-air flow was maintained at zero and the resulting pressure variation in the shroud indicated pumping ability.

Memorandum presenting an investigation to determine the effects of scale and compressibility on the forces, moments, and pressure distribution on a wing with an aspect ratio of 3 and a taper ratio of 0.5. Lift, drag, and pitching-moment data and the chordwise distribution of static pressure at seven spanwise stations are presented for several sets of Reynolds and Mach numbers. The results indicated that for all Mach and Reynolds numbers in the test range, no apparently flow separation existed near the leading edge of the wing for lift coefficients less than 0.3.

Report presenting an investigation to determine the low-speed longitudinal characteristics of an aspect ratio 4 triangular wing alone and in combination with a fuselage, vertical tail, and horizontal tail. The complete model consisted of a wing with a fuselage of fineness ratio 12.5, a thin, triangular, vertical tail, and two thin, unswept, all-movable horizontal tails of two different aspect ratios.

Report discussing the drag and pressure recovery of a model with a nose inlet with a parabolic arc at zero angle of attack. External drag coefficient and total-pressure recovery at the end of the diffuser were measured at a range of Mach numbers and mass-flow ratios.

The effectiveness of molybdenum disulfide MoS2 as a bearing lubricant was determined at high temperature and at high speeds. A 1-inch-bore ball bearing operated at temperatures to 1000 F, a speed of 1725 rpm, and a thrust load of 20 pounds when lubricated only with MoS2-air mist. A 75-millimeter-bore cageless roller bearing, provided with a MoS2-syrup coating before operation, operated at DN values to 1 x 10(exp 6) with a load of 368 pounds.

Report presenting an investigation of the low-speed, power-off stability and control characteristics of a model of the McDonnell XF3H-1 airplane. Flight testing occurred in the clean and slat- and flaps-extended conditions over a range of lift coefficients.

"At the request of the Bureau of Aeronautics, Navy Department, an investigation of the low-speed, power-off stability and control characteristics of a 1/10-scale model of the McDonnell XF3H-1 airplane has been made in the Langley free-flight tunnel. Flight tests of the model in the clean and in the slats-and-flaps-extended conditions were made over a lift-coefficient range from about 0.5 through the stall. Only low-altitude conditions were simulated and no attempt was made to determine the effect on the stability characteristics of freeing the controls" (p. 1).

Report presenting rocket-powered flight testing to determine the damping in roll of several wings of 0 degree and 45 degree quarter-chord-line sweep with various taper ratios for a range of Mach numbers. Damping in roll decreased with decreasing taper ratio at roughly the same rate for swept and unswept wings and also decreased by sweeping the quarter-chord line. The experimental results were also consistently lower than what was predicted by theory.