"Convenient charts are presented for computing the thrust, fuel consumption, and other performance values of a turbojet system. These charts take into account the effects of ram pressure, compressor pressure ratio, ratio of combustion-chamber-outlet temperature to atmospheric temperature, compressor efficiency, turbine efficiency, combustion efficiency, discharge-nozzle coefficient, losses in total pressure in the inlet to the jet-propulsion unit and in the combustion chamber, and variation in specific heats with temperature. The principal performance charts show clearly the effects of the primary variables and correction charts provide the effects of the secondary variables" (p. 1).

Report discussing an investigation of the effect of variations in pitch distribution on propeller efficiency at low Mach numbers. The three 10-foot-diameter propellers tested consisted of three blades mounted on a streamline body and were tested for a blade-angle range from 15 degrees to 60 degrees. Information about the propeller thrust, power coefficients, force-balance measurements, and total pressure in the propeller wake is provided.

"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 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.

"Column and plate compressive strengths of extruded 14S-T aluminum alloy were determined both within and beyond the elastic range from tests of flat-end H-section columns and from local-instability tests of H-, Z-, and channel-section columns. These tests are part of an extensive research investigation to provide data on the structural strength of various aircraft materials. The results are presented in the form of curves and charts that are suitable for use in the design and analysis of aircraft structures" (p. 1).

An analysis was made to determine the effect of rolling pull-out maneuvers on the wing and aileron loads of a typical fighter airplane, the P-47B. The results obtained indicate that higher loads are imposed upon wings and ailerons because of the rolling pull-out maneuver, than would be obtained by application of the loading requirements to which the airplane was designed. An increase of 102 lb or 15 percent of wing weight would be required if the wing were designed for rolling pull-out maneuver. It was also determined that the requirements by which the aileron was originally designed were inadequate.

Report presenting the use of the energy method to derive interaction equations that define the critical combinations of longitudinal and transverse direct stress for isotropic flat rectangular plates with four different edge conditions. Charts based on the interaction equations are presented for the four cases.

Report presenting tests of spin-recovery parachutes on six models of typical fighter and trainer airplanes conducted in the 20-foot free-spinning tunnel to obtain data for correlating model and full-scale results. Parachutes attached to the tail of the models, to the outer wing tip, to the inner wing tip, and to both wing tips were tested. Results regarding parachute construction, loading variations, effect of test altitude, and action of spin-recovery parachutes are provided.

Tests in Langley pressure tunnel of model XA-26 bomber were compared with those of A-26B (twin-engine attack bomber) and showed that static longitudinal stability, indicated by elevator-fixed neutral points, and variation of elevator deflection in straight and turning flight were good. Airplane possessed improved stability at low speeds which was attributed to pronounced stalling at root of production wing. At rudder-force reversal at speeds higher than those in flight tests, agreement in rudder-fixed and rudder-free static directional stability was good. Hinge moment obtained at zero sideslip was satisfactory for determining aileron forces in sideslip.

Report presenting a theoretical investigation of the buckling of an infinitely long flat plate with edges elastically restrained against rotation under combinations of longitudinal and transverse direct stress. Interaction curves are presented that give the critical combinations of stress for several different degrees of elastic edge restraint, including simple support and complete fixity.

Report presenting testing of a number of spin-recovery parachutes varying in size in order to determine the force exerted by the parachutes on the towline and the stability of the parachutes. The effects of modifications to the parachutes regarding towline tension and stability are also provided. Results regarding the parachute motions, air forces on parachutes, shock loads, and effects of modifications to line length and canopy vent are provided.

Report presenting a study of several sample helicopters in order to evaluate the effect of rotor-tip speed on hovering performance and limiting forward speed. The main purpose of the study was to determine whether hovering performance could be increased by the use of lower tip speeds without undue sacrifice in maximum forward speed. Results regarding typical helicopters, low-solidity helicopters, and high-speed helicopters are provided.

Results are reported of knock-limited tests of five aromatics, each individually blended with selected base fuels and tested with and without TEL, using 17.6, F-4, and F-3 small-scale engines. The five aromatics rated in the following order of decreasing antiknock effectiveness at fuel/air ratio 0.10: m-xylene, 1-isopropyl-4-methylbenzene, n-propylbenzene, isobutylbenzene, and n-butylbenzene.

Report presenting knock-limited performance tests of leaded blends of four pure aromatic hydrocarbons and six pure ethers with a base fuel in a full-scale aircraft-engine cylinder at two operating conditions to determine the antiknock effectiveness of additions of pure compounds to aviation fuels.

Report presenting knock-limited tests using F-4, F-3, and 17.6 small-scale engines and a full-scale cylinder on blends containing four different types of hydrocarbons. Each of the hydrocarbons was individually blended in various concentrations with three base fuels.

Report presenting testing of a double-row radial air-cooled engine to investigate overall cooling characteristics and to analyze what variations in temperature distribution were caused by variations in cooling-air pressure drop, power, and fuel-air ratio. Testing occurred over a range of engine powers.

Report presenting the horizontal and vertical components of the induced velocity in front of an inclined propeller in a horizontal stream obtained by a magnetic-analogy method. The problem was formulated in terms of the linear theory of the acceleration potential of an incompressible nonviscous fluid.

Report presenting the effects of large variations of lateral area on the lateral stability and control characteristics of a free-flying model when ailerons are used as the principal control as determined by flight tests. The effects of the lateral-force parameter were investigated for a wide range of values of the directional-stability parameter and the rotary-damping-in-yaw parameter.

"In conjunction with a program of research on the general problem of stability of airplanes in the climbing condition, tests have been made of a spring-loaded tab, which is referred to as a "springy tab," installed on the elevator of a low-wing scout bomber. The tab was arranged to deflect upward with decrease in speed which caused an increase in the pull force required to trim at low speeds and thereby increased the stick-free static longitudinal stability of the airplane. It was found that the springy tab would increase the stick-free stability in all flight conditions, would reduce the danger of inadvertent stalling because of the definite pull force required to stall the airplane with power on, would reduce the effect of center-of-gravity position on stick-free static stability, and would have little effect on the elevator stick forces in accelerated flght" (p. 1).

Report presenting a series of dynamic tests undertaken on a model of a hull of JRM-1 in order to provide information on the probable water loads during rough water landings. The impact acceleration and trim data are analyzed to show the trend of accelerations with wave size and length-height ratio.

Report presenting an investigation of the antiknock effectiveness of N-methyl-aniline and xylidines as fuel additives under severe engine operating conditions. 5-percent concentrations by weight were blended with an alkylate blending agent and a virgin-base gasoline.

Report discusses a series of force tests of a NACA 0009 elliptical semispan wing equipped with a flap that is either 50 percent of the wing area or 30 percent of the wing area. Information about the lift, hinge moment, and drag and pitching moment is provided.

From Introduction: "The purpose of this report is to gather together in one place information on the skipping characteristics of number of flying boats. A graph showing the influence of the hull form on the skipping characteristics is given which should be useful in laying out the proportions of the hull in preliminary design to insure good landing behavior."