A flight investigation in natural icing conditions was conducted to determine the effect of inlet ice formations on the performance of axial-flow turbojet engines. The results are presented for icing conditions ranging from a liquid-water content of 0.1 to 0.9 gram per cubic meter and water-droplet size from 10 to 27 microns at ambient-air temperature from 13 to 26 degrees F. The data show time histories of jet thrust, air flow, tail-pipe temperature, compressor efficiency, and icing parameters for each icing encounter. The effect of inlet-guide-vane icing was isolated and shown to account for approximately one-half the total reduction in performance caused by inlet icing.

Report presenting an investigation at low speed in the 300 mph tunnel to determine the static aerodynamic forces and moments on a missile model during simulated launching from 25-percent-semispan and wing-tip locations of a wing-fuselage combination. Results regarding the differences in location and effects induced by the fuselage are provided.

Report presenting an investigation to determine the effects of plan-form taper on the aerodynamic characteristics of a series of symmetrical, unswept wings with thicknesses of 8-percent chord. The wings were tested with four different bodies of revolution over a range of Mach numbers. Results regarding the lift, drag, pitching-moment, lift-curve slope, lift-drag ratio, and pitching-moment curve are provided.

Report presenting an investigation to determine the blade torsional deflection of three supersonic-type propellers at various operating conditions. Blade-torsional deflection was found to produce appreciable results that can be predicted by theory with good accuracy. Results regarding the efficiency, thrust coefficient, and power coefficient are provided.

Report presenting measurements of the intensity of buffeting experienced by the Douglas D-558-II research airplane at a range of Mach numbers. Buffeting was encountered at both subsonic and supersonic Mach numbers and the intensity of the buffeting varied with Mach number and airplane normal-force coefficient.

Report presenting the results of testing in the transonic range of four flutter airfoils attached to a freely falling body. Failures of the airfoils were metered and recorded in order to determine the Mach numbers and altitudes of failure.

An investigation is being conducted to determine the altitude performance characteristics of the British Nene II engine and its components. The present paper presents the preliminary results obtained using a standard jet nozzle. The test results presented are for conditions simulating altitudes from sea level to 60,000 feet and ram pressure ratios from 1.0 to 2.3. These ram pressure ratios correspond to flight Mach numbers between zero and 1.16 assuming a 100 percent ram recovery.

Powered models of three different flying boats were landed in oncoming wave of various heights and lengths. The resulting motions and acceleration were recorded to survey the effects of varying the trim at landing, the deceleration after landing, and the size of the waves. One of the models had an unusually long afterbody. The data for landing with normal rates of deceleration indicated that the most severe motions and accelerations were likely to occur at some period of the landing run subsequent to the initial impact.

Report presenting the effect of channel geometry on flame quenching, as calculated on the basis of average active particle chain lengths, is related among six different geometries: plane parallel plates of infinite extent, cylindrical tubes, rectangular slots, cylindrical annuli, and tubes of elliptical and equilaterally triangular shape. The results indicated that the observed variation of flame quenching as a function of quenching geometry may be successfully predicted for a range of pressures and for rich as well as lean propane-air flames.

In accordance with a request of the Bureau of Aeronautics, Navy Department, tests were performed in the Langley 20-foot free-spinning tunnel to determine the spin and recovery characteristics of a 1/24 scale model of the Grumman XTB3F-1 airplane. The airplane is a two-place, midwing torpedo bomber equipped with a tractor propeller and an auxiliary jet engine. The effect of control setting and movement on the erect and inverted spin and recovery characteristics of the model were determined for the normal loading.

"A spin investigation has been conducted in the Langley 20-foot free-spinning tunnel on a 1/24-scale model of the North American XP-86 airplane. The effects of control settings and movements upon the erect and inverted spin and recovery characteristics of the model were determined for the design gross weight loading. The long-range loading was also investigated and the effects of extending slats and dive flaps were determined" (p. 1).

"The spin and recovery characteristics of the Curtiss-Wright XP-87 airplane, as well as the spin-recovery parachute requirements, the control forces that would be encountered in the spin, and the best method for the crew to attempt an emergency escape, are presented in this report. The characteristics were estimated rather than determined by model tests because the XP-87 dimensional and mass characteristics were considered to be noncritical and because data were available from model tests of several similar airplanes. The study indicated that the recovery characteristics of the airplane will be satisfactory for all loadings if the controls are reversed fully and rapidly" (p. 1).

"An investigation has been conducted in the Langley 20-foot free-spinning tunnel to determine the spin and recovery characteristics of a 0.057-scale model of the modified Chance Vought XF7U-1 airplane. The primary change in the design from that previously tested was a revision of the twin vertical tails. Tests were also made to determine the effect of installation of external wing tanks" (p. 1).

Memorandum presenting an investigation of the performance of inlet configurations with a forebody designed for isentropic external compression at a nominal Mach number of 5.6. At zero angle of attack, all the configurations yielded larger total-pressure recoveries than had previously been obtained with a single-conical-shock inlet. Results regarding the flow about the forebody, inlet performance, and performance comparisons are provided.

Memorandum presenting an investigation of the performance of inlet configurations with a forebody designed for isentropic external compression at a nominal Mach number of 5.6. At zero angle of attack, all of the configurations yielded larger total-pressure recoveries than had previously been obtianed with a single-conical-shock inlet. Results regarding the flow about the forebody and performance comparisons are provided.

Report presenting an investigation in the transonic blowdown tunnel to determine the effects of variations in inlet lip swagger from 0 to 60 degrees on the internal-flow characteristics of an unswept semielliptical scoop-type air-inlet model without boundary-layer control. Tests were made for a range of Mach numbers and mass-flow ratios. Results regarding the flow over the fuselage nose, total-pressure recovery at inlet, flow distortions at inlet, and inlet-design considerations are presented.

Report presenting a test-stand investigation conducted on a rectangular ramjet engine design for installation in an aircraft wing. The engine operated without excessive engine noise or vibration over the entire range of operating conditions. Results regarding inlet velocity, exhaust flame characteristics, fuel-air ratio, and total-temperature rise are provided.

"Results are reported of current studies at the Forest Products Laboratory to develop a metal-bonding adhesive with greater resistance to temperatures up to 600 degrees Fahrenheit that is easier to use than present ones. Most promising is a formulation of phenol and epoxy resins modified with hexamethylenetetramine and supplied for use as a dry tape supported on a glass-mat base" (p. 1).

Drag and longitudinal trim at low lift of the North American YF-100A airplane at Mach numbers from 0.76 to 1.77 as determined from the flight test of a 0.11-scale rocket model are presented herein. Also included are some longitudinal stability and some qualitative pitch-damping data.

Report presenting a flight investigation to determine the effectiveness of three fuselage indentations for reducing the pressure drag of a 45 degree sweptback-wing-body configuration at a range of Mach numbers. The results indicate that the supersonic area rule can be used to determine indentations with low pressure drag over a Mach number range in which the blunt leading edge is subsonic. Information about total drag and pressure drag is provided.

Report presenting an investigation in an altitude test chamber using a turbojet engine equipped with an afterburner and ejector to compare directly two techniques of determining thrust that are both applicable to flight installations. One method uses a swinging uncooled rake at the ejector outlet while the other requires extensive instrumentation to measure the momentum forces of systems and the force on the internal surface of the ejector nozzle. Results regarding the swinging-rake technique and internal-pressure technique are provided.

From Introduction: "As a part of the comprehensive investigation of the XJ34-WE-32 engine conducted in the NACA Lewis altitude wind tunnel, the over-all-performance was determined over a range of altitudes and flight Mach numbers. Other phases of the investigation are reported in reference 1. The results are given in tables and also in graphical form to show the trends of engine performance associated with changes of altitude, flight Mach number, and exhaust-nozzle area."

"An investigation has been completed in the Langley 20-foot free-spinning tunnel on a l/18-scale model of the Ryan X-13 airplane to determine its spin, recovery, and tumbling characteristics, and to determine the minimum altitude from which a belly landing could be made in case of power failure in hovering flight. Model spin tests were conducted with and without simulated engine rotation. Tests without simulated engine rotation indicated two types of spins: one, a slightly oscillatory flat spin; and the other, a violently oscillatory spin" (p. 1).

The results of an experimental investigation of the load distribution over two triangular wings in sideslip at Mach numbers from 1.20 to 1.79 are presented and compared with theory. The two wings tested have identical plan form, 45 degrees sweepback of the leading edge, and an aspect ratio of 4.0. One model was composed of round-nose airfoil sections and the other of sharp-nose, biconvex sections. For both wings the maximum thickness of streamwise sections was 6 percent and was located at the 30-percent chord.