Report discussing tests on the N9M-2 airplane to evaluate the airplane efficiency factor and to investigate the characteristics of the aeroboost in the elevon control system. The efficiency factor compared reasonably well to conventional airplanes and the aeroboost system and valve-chatter tests were satisfactory.

"A study has been made of the variation of seaplane hull weight with length-beam ratio in a systematic series of hulls designed for constant gross weight and similar spray characteristics. It is found that increases in the length-beam ratio bring about small reductions in the hull weight if it is assumed that seaplanes having the same weight and bottom shape will be designed for the same load factor. A short discussion is also given to show the reduction in load factor that may occur with high length-beam ratios" (p. 1).

Memorandum presenting an analytical method developed that gives two independent means of obtaining the total-temperature ratio across a ram jet or across a turbojet tail-pipe burner without direct measurement of the final gas temperature. Experimental verification of the analysis has been obtained with a 20-inch ram jet over a wide range of operating conditions.

Report presenting an investigation of three transonic fuselage-inlet installations designed to maintain substream velocities on the body ahead of air inlets. Surface pressures and inlet total pressures were measured at the tops of the test configurations for wide ranges of inlet-velocity ratio and angles of attack. Results indicated that substream velocities were maintained on all three noses over the angle of attack ranges and inlet-velocity ratio useful for high-speed flight.

Memorandum presenting a flight investigation conducted on a 20-inch-diameter steady-flow ramjet at a range of altitudes and free-stream Mach numbers. Results regarding the variation of combustion efficiency with fuel-air ratio and pressure altitude, effects of combustion-chamber-inlet velocity, and altitude on the operating range of fuel-air ratio are provided. The ramjet unit operated smoothly over the entire range of velocities and altitudes with the exception of occasional rough operation at excessively rich mixtures.

Report presenting an experimental investigation at zero flight speed and sea-level conditions on a 4000-pound-thrust centrifugal-flow-type turbojet engine to determine the amount of thrust augmentation obtainable at maximum rotor speed by the injection of water, alcohol, and water-alcohol mixtures at the compressor inlets. A maximum thrust augmentation of 26 percent was obtained by the injection of 4.5 pounds per second of water and 2.0 pounds per second of alcohol. Results regarding the tail-pipe gas temperature, air-flow and compressor-outlet pressure, fuel flow, specific liquid consumption, and thrust augmentation are provided.

Report presenting a low-speed wind-tunnel investigation to determine the characteristics of deflectable wing-tip ailerons on an untapered 45 degree sweptback semispan wing. Ailerons with triangular and parallelogram plan forms with a maximum chord of 0.625 wing chord and a flat-plat profile were investigated. The aerodynamic characteristics in pitch and lateral control characteristics are included.

"The principle of operation of a device to control the distribution of fuel to any number of discharge nozzles of a gas-turbine engine is presented. A description of an experimental model of the device and the results of a bench investigation are presented. This device controlled the flow to four discharge nozzles within 2 percent of perfect distribution over a wide range of fuel flow and was unaffected by uneven discharge-nozzle pressures" (p. 1).

Report presenting an investigation of the stability of models of the jettisonable nose sections of D-558 airplanes in two phases. The effects of center-of-gravity location and stabilizing fins of various sizes were also determined. The noses were found to tumble end over end at an approximately horizontal axis, which may be dangerous to the pilot if the nose is jettisoned while the airplane is traveling at a high rate of speed.

Report presenting an investigation of a 42 degree sweptback wing of aspect ratio 4, taper ratio 0.625, and NACA 64-series airfoil sections to study several proposed devices for increasing the maximum lift coefficient and improving the longitudinal stability characteristics of sweptback wings at the stall. Some of the devices tested included leading-edge flaps and slats, trailing-edge split and extended split flaps, upper-surface split flaps, and upper-surface fences. The results regarding the characteristics of the devices and the wing-fuselage combinations are described.

Report presenting an investigation of surface static pressures over the outer and inner surfaces of the cockpit canopies on the Grumman F6F-3, Curtiss SB2C-4E, and Grumman F8F-1 airplanes in the full-scale tunnel. Results regarding the external pressure distribution and internal static pressure are provided.

Report presenting an investigation of the problem of applying controls to low-aspect-ratio wings of triangular plan form by using the NACA wing-flow method with parallel-sided models with sharp leading and trailing edges. Results regarding the data analysis, Reynolds number and separation effects, flap effectiveness, plan-form characteristics, angle of zero lift, and triangular plan-form flying-wing characteristics are provided.

Memorandum presenting wind-tunnel tests conducted to determine the high-speed stability and control characteristics of an airplane model with a sweptback wing and tail. The aerodynamic coefficients and the longitudinal- and lateral-control characteristics of the plain wing-fuselage-tail combination are included. Results regarding lift, drag, and pitching moment, longitudinal characteristics, lateral characteristics, wing leading-edge slate, and fuselage-side dive brakes are provided.

Report discussing an investigation of two sweptback wings of different plan form in order to determine the effects of adding a triangular area to the inboard section of a conventional sweptback wing as a way to create a wing with two stages of sweepback. Lift, drag, and pitching-moment characteristics are provided for a range of Mach numbers.

Report presenting a discussion of the aerodynamic forces and moments on inclined bodies of revolution. An approximate theory to allow for the effects of viscosity is developed and applied. Results regarding the variation of lift and pitching moment, and center of gravity are provided.

Report presenting an investigation to determine the aerodynamic characteristics in sideslip of a triangular wing of aspect ratio 2.04 in combination with a body of fineness ratio 12.5 and a vertical tail surface. The body combined with the triangular plan-form wing caused no significant changes in the lift characteristics of the wing and only a 1-percent decrease in the static margin. Results regarding the longitudinal characteristics, lateral and directional characteristics, and estimation of tail and rudder effectiveness are provided.

This report presents measurements of the lift and pitching-moment characteristics of a straight wing of aspect ratio 4, taper ratio 0.5, having a symmetrical double-wedge airfoil section with a maximum thickness of 4.4-percent chord. The tests were conducted in the Mach number range 0.51 to 1.20, Reynolds numbers 380,000 to 660,000, by the NACA wing-flow method. The results are compared with theory and with wind-tunnel tests of a similar model. It is indicated that in the Mach number range 0.82 to 1.00 the model surface, profile, and test Reynolds number all would be very important considerations in any attempt to study or predict full-scale characteristics from small-model tests.

This report contains the results of a high-speed wind-tunnel investigation of the effectiveness of a 10-percent-chord plain flap on the NACA 65-210 airfoil section. The results include an indication of the lift-producing characteristics and the effectiveness of the 10-percent-chord flap. From a comparison of the characteristics of the 10-percent-chord flap with those of a 20-percent-chord flap it was concluded that, although a reduction in flap-chord ratio from 0.20 to 0.10 lessens the severity of the effectiveness loss at supercritical speeds, the 20-percent-chord flap is more effective throughout the entire range of Mach numbers from 0.3 to 0.875.

"An investigation has been made in the Langley 16-foot high-speed tunnel to determine the propeller-section characteristics by measuring the pressure distribution on the airfoil sections of a rotating propeller. The pressures were measured at nine radial stations on an NACA 10-(3)(08)-03 design two-blade propeller. This paper presents the results of the pressure measurements in the form of normal-force and moment coefficients and covers a range of nominal angle of attack (simple blade element theory) from 0 degrees to 4 degrees for a section Mach number range of approximately 0.6 to 1.15 for the outboard stations and approximately 0.3 to 0.6 for inboard stations" (p. 1).

Report presenting an investigation to determine the effects of several leading-edge modifications on the maximum lift and pitching-moment characteristics on a large-scale 45 degree swept-forward wing. A full-span leading-edge flap deflected 30 degrees down tended to give the largest gain of maximum lift. Results regarding the plain leading-edge flaps and cambered nose are explored.

Report presenting the pressure distribution over a highly swept wing at supersonic speeds to provide data for a comparison of measured and predicted loadings. The wing for this investigation had 63 degrees of sweepback of the leading edge, an aspect ratio of 3.5, and a taper ratio of 0.25. Over the regions influenced by the wing tip and trailing edge, the effects of viscosity apparently are responsible for the poorer agreement between theory and experiment.

Report presents the results of a study of combustion in a spark-ignition engine given in NACA Technical Reports 704 and 727. The present investigation was made with the NACA high-speed motion-picture camera, operating at 40,000 photographs a second, and with a cathode-ray oscillograph operating on a piezoelectric pick-up in the combustion chamber. Photographs are presented showing that the origin of knock is not necessarily in the end gas. The data obtained indicates that knock takes place only in a part of the cylinder charge which has been previously ignited either by autoignition or by the passage of the flame fronts but which has not burned to completion. Mottled regions in the high-speed Schlieren photographs are demonstrated to represent combustion regions.

A chart is presented for the values of the coefficient in the formula for the critical compressive stress at which buckling may be expected to occur in outstanding flanges. These flanges are flat rectangular plates supported along the loaded edges, supported and elastically restrained along one unloaded edge, and free along the other unloaded edge. The mathematical derivations of the formulas required for construction of the chart are given.

"An approximate method for determining the convective cooling requirement in the laminar boundary-layer region of a body of revolution in high-speed flight was developed and applied to an example body. The cooling requirement for the example body was determined as a function of Mach number, altitude, size, and a surface-temperature parameter. The maximum value of Mach number considered was 3.0 and the altitudes considered were those within the lower constant-temperature region of the atmosphere (40,000 to 120,000 ft.)" (p. 463).