From Introduction: "An investigation of the power-plant installation of a single-engine torpedo-bomber-type airplane has been conducted in the NACA Cleveland altitude wind tunnel at the request of the Bureau of Aeronautics, Navy Department. A similar investigation was previously conducted on a three-tenths scale mock-up of the forward portion of the fuselage of this airplane in the Langley 20-foot tunnel. (See reference 1)."

Note presenting a solution for the buckling load and load carried after buckling of a clamped rectangular plate with a width-length ratio of 1:4 under combined normal pressure and axial load. The results indicate that normal pressure causes a smaller increase in the buckling load of plates with clamped edges than of plates with simply supported edges.

Note presenting an investigation to compare the effectiveness of two basic methods of cooling a turbosupercharger and to obtain data on the temperature level and distribution in the turbine wheel. Turbine-wheel temperatures were obtained for various conditions of cooling-air mass flow, exhaust-gas temperature, and exhaust-gas mass flow. Modified forms of the standard cooling caps were used to allow for the installation of temperature-measuring devices.

"Dynamic yawing effects on vertical tail loads are considered by a theory of flat yawing maneuvers. A comparison is shown between computed loads and the loads measured in flight in a fighter airplane. The dynamic effects were investigated on a large flying boat for both an abrupt rudder deflection and a sinusoidal rudder deflection" (p. 1).

"The gross weight, beam, and afterbody length of 12 contemporary flying boats and amphibians with pointed afterbodies are tabulated and correlated. For most of the hulls considered, the afterbody length-beam ratios are shown to be directly proportion to the gross-load coefficients" (p. 1).

Report presenting the knock-limited performance of nine fuels comprising isolated members of four classes of hydrocarbons in the form of three-dimensional plots of fuel-air ratio, compression temperature, and compression-air density.

Report presenting the performance of a 22-inch-diameter pulse-jet engine using a net of low-loss modified air valves at ram pressures equivalent to simulated flight speeds. Results regarding combustion-air weight flow, flight thrust, maximum combustion-chamber pressure, specific fuel consumption, pressure cycle, and valve life are provided.

Report discussing the results of accelerated erosion tests to determine the separate effects of the passage of fuel, water, and ice particles through a supercharger. Recommendations for preventing erosion are provided, including materials choice and joint design.

Testing of a 10-foot-diameter three-blade Curtiss 89301-15 propeller with Clark Y blade sections was conducted in the 16-foot high-speed tunnel to determine the effect of simulated ice on the aerodynamic characteristics of the propeller. The propellers were tested on a 2000-horsepower dynamometer at rotational speed 1800 rpm at several blade angles and airspeeds. Results regarding the effect of icing and constant-power propeller operation are provided.

Note presenting an investigation of the heat transfer to a surface from plane heated-air jets discharged tangentially to the surface to provide heat-transfer relationships required in the design of heated-air jet installations for aircraft windshield fog prevention. Experimental temperature, velocity, and heat-transfer data were obtained by tests in which the initial jet temperature and velocity were varied.

Note presenting an investigation of the heat transfer to a surface from plane heated-air jets discharged tangentially to the surface was conducted to provide heat-transfer relationships required in the design of heated-air jet installations for aircraft windshield fog prevention. Experimental temperature, velocity, and heat-transfer data were obtained by tests in which the initial jet temperature and velocity were varied.

"Tests have been made at high speeds to determine the drag of models, simulating propeller shanks, in the form of a circular cylinder and three airfoils, the NACA 16-025, the NACA 16-040, and the NACA 16-040 with the rear 25 percent chord cut off. All the models had a maximum thickness of 4 1/2 inches to conform with average propeller-shank dimensions and a span of 20 1/4 inches. For the tests the models were supported perpendicular to the lower surface of the wing of an XP-51 airplane (p. 277).

Report discussing measurements of the overall drag coefficient of the XP-51 in dives using three different methods. The three instruments used to measure drag variation are compared for accuracy. A comparison of the drag results obtained from this test are also compared to the results obtained from previous wind tunnel testing.

Report presenting tests of three airplanes in an effort to develop elevators that would provide stick forces in steady turns within the limits required by the Army and Navy handling-qualities specifications over a large range of center-of-gravity positions.

"Flight tests were conducted on a twin-engine fighter airplane at pressure altitudes up to 10,000 feet with simulated conditions of moderate, heavy, and excessive rain to determine the increase in enthalpy of the charge air due to the turbosupercharger, to determine the rate of enthalpy increase of the charge air resulting from a sudden increase of engine power, and to compare the conditions that caused induction-system icing in flight with those that resulted in icing of the same carburetor and supercharger inlet elbow in laboratory tests" (p. 1).

Report presenting a method for determining the jet-boundary and plan-form corrections necessary for application to test data for a partial-span model with a reflection plane, an end plate, or no end plate in a closed circular wind tunnel. Good agreement with three different conditions was obtained with flaps neutral at values of lift coefficient below the stall and somewhat less satisfactory agreement in the region of maximum lift coefficient or with flaps deflected.

In part I of the paper the theory of flame propagation is developed along the lines followed by Frank-Kamenetsky and one of the writers. The development of chain processes in flames is considered. A basis is given for the application of the method of stationary concentrations to reactions in flames; reactions with branching chains are analyzed. The case of a diffusion coefficient different from the coefficient of temperature conductivity is considered.

Report presenting an investigation in the full-scale tunnel to determine the thickness and shape of profile of the boundary layer on the fuselage of a typical monoplane fighter airplane with a single liquid-cooled engine. The results indicate that the maximum displacement thickness was nearly 1.2 inches and was at the most rearward station.

Report presenting the dimensional parameters of ram-compression power plants as related to their thrust and economy performance and an investigation of the speed and range performance possibilities of a family of pilotless airplanes powered with one of the power plants. The analysis of the power plants includes the power-plant configuration, aerodynamic and thermodynamic cycle, constants used in the computations, power-plant performance, and operation of the power unit with fixed areas at various flight speeds. The investigation of the aircraft included a description of its characteristics, speed, range, effect of wing selection of speed, and effect of size on performance.

Report presenting the results of calibrations to determine axial and transverse strain sensitivities for 15 types of single-element, multistrand wire strain gages. The gages were separated into those which had positive average ratios of transverse sensitivity and those which had negative transverse sensitivity.

"This report describes an apparatus enabling measurements of bodies to be made photographically, where other methods would be difficult. It is especially useful in the case of airscrews and wing models. The utility of the machine is shown by a few examples of profile records" (p. 1).

From Summary: "A pressure-distribution investigation was made in the Langley 7- by 10-foot tunnel of a plug-type spoiler-slot aileron on a semispan tapered-wing model of a typical fighter airplane equipped with full-span slotted flaps. The results of the investigation indicate peak pressure on a plug-type spoiler-slot aileron that may result in a compressibility shock on the plug aileron at high speed. The maximum loads on the plug aileron occurred in the high-speed condition for maximum up aileron deflection."

Report presenting an investigation for the determination of the behavior of ceramic bodies in tension at elevated temperatures for the purpose of determining data for the design of ceramic blades for gas turbines. Observations were made of six special ceramic bodies in order to determine their tensile strength and creep during prolonged loading under a range of stresses and temperatures.

Note presenting a method by which the directional stability derivative, which is the rate of change of yawing-moment coefficient with sideslip angle, can be evaluated for a conventional airplane from flight records of a lateral or directional oscillation. When applied to conventional airplanes flying at low to moderate lift coefficients, the assumptions involved in this simplified method produce negligible error.