From Introduction: "In an incomprehensible medium, the mutual interference of a fuselage and wing of high-aspect ratio (to which lifting-line theory is applicable) has been treated by Lennertz, Wiselsberger, Pepper, and Multhopp in reference 1, 2, 3, and 4. It is the purpose of this note to treat the effect of on the aerodynamic loading of the mutual interference between a low-aspect-ratio pointed wing and a fuselage consisting of a slender body of revolution."

"An altitude-test-chamber investigation was conducted to determine the operational characteristics and altitude blow-out limits of a Solar afterburner in a 24C engine. At rated engine speed and maximum permissible turbine-discharge temperature, the altitude limit as determined by combustion blow-out occurred as a band of unstable operation of about 8000 feet altitude in width with maximum altitude limits from 32,000 feet at a Mach number of 0.3 to about 42,000 feet at a Mach number of 1.0. The maximum fuel-air ratio of the afterburner, as limited by maximum permissible turbine-discharge gas temperatures at rated engine speed, varied between 0.0295 and 0.0380 over a range of flight Mach numbers from 0.25 to 1.0 and at altitudes of 20,000 and 30,000 feet" (p. 1).

"A theoretical analysis is presented for obtaining by use of Theodorsen's propeller theory the load distribution along a propeller radius to give the optimum propeller efficiency for any design condition. Examples are included to illustrate the method of obtaining the optimum load distributions for both single-rotating and dual-rotating propellers" (p. 1).

"A bibliography of NACA papers on rotating-wing aircraft issued up to July 1948 is presented. The list of papers is subdivided for ready reference under appropriate subject headings, and the titles are listed chronologically within each subject" (p. 1).

"A series of calculations of the dynamic response of airplane wings to gusts were made with the purpose of showing the relative response of a reference airplane, the DC-3 airplane, and of newer types of airplanes represented by the DC-4, DC-6, and L-49 airplanes. Additional calculations were made for the DC-6 airplane to show the effects of speed and altitude. On the basis of the method of calculation used and the conditions selected for analysis, it is indicated that: 1) The newer airplanes show appreciably greater dynamic stress in gusts then does the reference airplane; 2) Increasing the forward speed or the operating altitude results in an increase of the dynamic stress ratio for the gust with a gradient distance of 10 chords" (p. 1).

Note presenting a theoretical analysis of the characteristics of constant-chord full-span control surfaces on thin triangular wings at supersonic speeds by use of methods based on the linearized equation for supersonic flow. Expressions were found for the lift effectiveness, pitching-moment coefficient, hinge-moment coefficient due to control deflection, and hinge-moment coefficient due to angle of attack.

Report presenting a theoretical analysis of the characteristics of constant-chord partial-span control surfaces on thin triangular wings at supersonic speeds by use of methods based on the linearized theory for supersonic flow. Two cases were treated with the analysis. Results regarding lift coefficient, rolling-moment coefficient, and hinge-moment coefficient due to flap deflection, hinge-moment coefficient due to angle of attack, and the pitching-moment coefficient due to flap lift.

Contains charts for use in determining preliminary values of the spanwise-load, shear, bending-moment, and accumulated-torque distributions of swept wings. The charts are based on strip theory and include four aerodynamic-load distributions, two section-moment distributions, and two inertia-load distributions. The taper ratios considered cover the range from 1.0 to 0 and the results are applicable to any angle of sweep.

Charts are provided for the estimation and progressive adjustment of two independent variables on which the calculations are based. Additional charts are provided for the graphical calculation of the composition.

"The theoretical critical stress is derived for a simply supported curved rectangular panel in axial compression having a central chordwise stiffener offering no torsional restraint. The results are presented in the form of computed curves and a table. Because a panel of moderate or large curvature buckles in compression at a stress considerably below the theoretical value, a method is suggested to aid in determining the critical stress for use in design" (p. 1).

Note presenting a device that measures the velocity of sound in fluids at stagnation and is especially adaptable to turbine and compressor testing for which the composition of the working fluid may be in doubt. The Helmholtz resonator is used for measuring sonic velocity and compressor Mach number in these devices.

Report discussing an investigation of the vertical plane of the elevator hinge line of a powered model of a bomber to determine the values of downwash and the dynamic-pressure ratio. The equations for calculating these values and the testing procedures are described.

Wind-tunnel tests of a simplified nacelle on a semispan wing having approximately 35 degrees of sweepback were made at low speeds to evaluate the effects of the nacelle on the aerodynamic characteristics of the wing. Force, moment, and pressure-distribution measurements are presented for the nacelle underslung and centrally mounted on the wing and mounted on a strut below the wing.

Report presenting an investigation with a ram-jet combustion chamber to determine the effect of fuel-air ratio and the inlet-air parameters of pressure, temperature, and velocity on combustion limit, combustion efficiency, and flame length.

Note presenting an experimental investigation at low airspeeds of the filling effect observed when a screen or similar resistance is placed across a diffuser. The filling effect is found to be real in that screens can prevent separation or restore separated flow in diffusers even of extreme divergence and to depend principally on screen location and pressure-drop coefficient of the screen.

Report presenting an investigation to determine the influence of strength and ductility on the room-temperature burst characteristics of solid disks, disks with large-diameter central holes, and disks with small-diameter central holes. Results regarding the stress concentrations causing fracture, ratio of disk strength to tensile strength, effect of small holes, and evaluation of most ductile materials are provided.

Report presenting a low-speed wind-tunnel investigation to determine the effect of taper ratio on the static and yawing stability derivatives of three tapered wings with a constant sweepback of 45 degrees at the quarter-chord line and with an aspect ratio of 2.61 but different taper ratios. Results regarding the characteristics in straight flow and yawing flow are provided.

Report presenting testing of six, 3-inch-chord symmetrical airfoil sections with systemic variations in thickness and maximum-thickness location at Mach numbers near flight values for propeller-shank sections. The tests were performed to illustrate the effects of compressibility on the flow past thick symmetrical airfoil sections. Results regarding flow characteristics and airfoil force characteristics are provided.

Report presenting testing of the low-speed aerodynamic characteristics of the NACA 66-series airfoil section in the two-dimensional low-turbulence pressure tunnel. Results regarding the critical-speed characteristics and low-speed characteristics are provided.

Report presenting testing of a twin-scoop duct inlet that enclosed 37.2 percent of the forebody circumference at Mach numbers between 1.36 and 2.01. The approach to each scoop consisted of a ramp that deflected the flow to create an oblique shock wave in front of the duct entrance. Results regarding the inlet proportions, ramp angle, slots, and angle of incidence are provided.

Report presenting aerodynamic and icing investigations on a model of a turbojet-engine nacelle in order to provide icing protection for the engine, protective screen, and accessory housing by the introduction of hot gases into the inlet-air stream. Adequate ice protection was afforded when the minimum kinetic temperature in the protective screen was greater than 32 degrees Fahrenheit.

Report presenting an experimental investigation of thrust augmentation of an axial-flow-type turbojet engine with a 4000-pound-thrust rating using a water-alcohol injection at the compressor inlet at sea-level conditions and zero ram. Three injection systems were investigated in order to obtain satisfactory atomization and distribution of the injected liquids. Results regarding engine performance and engine operation are provided.

Report presenting testing of a low-acceleration transonic flutter test vehicle to obtain flutter data on two similar sweptback wings which indicated that wing flutter was symmetrical in mode. Results regarding flight and flutter characteristics for the FR-1-B are provided.

Note presenting a determination of the effect of combined stresses on the fracture strength of 75S-T aluminum alloy by applying axial loads and internal pressure to thin-wall drawn tubes. Tubular extrusions of 75S-T aluminum alloy rupture in substantial agreement with the critical shear stress law for fracture.