Report discussing the division of load among the wing, fuselage, and tail for several aircraft configurations at subsonic and supersonic speeds. The load that each component carries at various Mach numbers and angles of attack is described.

From Wing Thickness: "A brief review of the effect of wing thickness and thickness distribution on the high-speed performance and stability characteristics of a representative configuration is presented."

Report presenting visual observations and flow analyses made of annular liquid flow with cocurrent air flow in 2- and 4-inch-diameter horizontal transparent tubes. The experiments occurred over a range of air mass velocities, air temperatures, and Reynolds numbers. Results regarding the velocity and thickness of liquid films, description of water-film disturbances, effect of flow variables on liquid-film characteristics, and relation between disturbances and flow conditions are provided.

Memorandum presenting a systematic study to determine the effect of molecular structure on the flammability limits of pure hydrocarbon-air mixtures at reduced pressures and room temperature. This report presents results obtained for 17 pure normal paraffins, branched paraffins, and mono-olefins. Results regarding experimental variables and experimental observations are provided.

Report presenting testing of rocket-powered models flown at transonic speeds to determine the effect of nacelle location on zero-lift drag. Low drag was obtained between M = 0.80 and M = 0.91 for all the nacelle positions investigated. Nacelles located at the wing tips gave the lowest drag, which was less than the drag of the combination without the nacelles over most of the speed range.

The drag of a body alone, six triangular wings of various aspect ratios, and the combinations were measured at Mach numbers of 1.50 and 2.02 at a Reynolds number of 5.5 million (based on the body length). The experimental drag-interference results were in accordance with calculations based on NACA RM A9E19, 1949, with skin-friction effects taken into account, the interference effect being principally the result of fixing transition on the body by adding a wing.

Report presenting a study of a large amount of data pertaining to high-speed buffet boundaries of various airplane configurations. The data indicate a strong influence of wing configuration on buffet boundaries. Results regarding low-lift buffeting, high-lift buffeting, buffet boundaries, and buffet intensity are provided.

The effects of fineness ratio (14.2 and 12.2) and boattailing on aerodynamic characteristics of four bodies of revolution at Mach numbers from 1.50 to 1.99 within a range of angles of attack from 0 degrees 10 degrees at an approximate Reynolds number of 35x10(superscript)6 based on body length were investigated. A comparison of experimental data with available theory is included. At zero angle of attack, fineness ratio has no appreciable effect on model characteristics while boattailing and boattail convergence significantly affect fore drag and base drag.

Report presenting the effects of variation of trailing-edge angle and trailing-edge thickness on the lift characteristics of a 10-percent-chord thick symmetrical NACA airfoil section with a 25-percent-chord plain flap as determined from wind tunnel tests over a range of Mach numbers. Results regarding the section lift and pitching-moment characteristics, variation of lift coefficient with flap deflection, schileren photographs, and effect of angle of attack are provided.

The factors affecting the performance of ejector suitable for aircraft cooling are investigated theoretically and experimentally. The investigation covers a range of shroud-to-nozzle diameter ratios from 1.1 to 1.6, of shroud lengths from 0.2 to 2.28 nozzle diameters, of secondary-to-primary weight-flow ratios from 0 to 0.12, and of ambient-to-nozzle pressure ratios from 0.7 to 0.06. The results of a simplified theoretical analysis based on each type of flow are in good agreement with those experimentally obtained.

Memorandum presenting an investigation conducted at Mach number 1.90 to determine if Helmholtz resonators can be used in a typical ramjet configuration to damp pressure pulsations associated with shock oscillations. Only one of the two resonators was found to effectively damp pressure pulsations that occurred when the ram jet was operating in the vicinity of its peak pressure recovery. Neither was found to effectively damp pressure pulsations over the entire range of ramjet operating conditions.

The effects of mass-flow ratio on the additive drag and normal-shock position of a single oblique-shock diffuser are presented. Also evaluated is the variation with operating condition of the velocity distribution at the combustion-chamber inlet. A comparison with connected-pipe data is included.

"The significance of additive drag is discussed and equations for determining its approximate value are derived. Charts are presented giving values of additive drag for open-nose inlets and for annular-nose inlets with conical flow at the inlet. The effects of variable inlet total-pressure recovery and static pressures on the center body are investigated, and an analytical method of predicting the variation of pressure on the center body with mass-flow ratio is given" (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.

From Introduction: "This report shows correlation between actual transient data obtained from the engine and solutions to a simulated system set up on an analog computer. Data are presented for response of engine speed to changes in set speed when the power plant was being controlled by a relay-type electronic governor that acted to maintain set speed by varying propeller pitch. Correlation obtained for sea-level conditions between actual time data and analog solutions is discussed."

A semiempirical method, in which potential theory is arbitrarily combined with an approximate viscous theory, for calculating the aerodynamic pitching moments for bodies of revolution is presented. The method can also be used for calculating the lift and drag forces. The calculated and experimental force and moment characteristics of 15 bodies of revolution are compared.

Report presenting the results of a theoretical and experimental study of ramjet diffuser flow pulsing, commonly referred to as a buzz condition, with and without combustion. The acoustical resonance properties of ram jets are an important factor in establishing the frequency of diffuser flow pulsations.

From Introduction: "Altitude-chamber and wind-tunnel investigations of the performance of turbojet engines such as those reported in references 1 to 4 have shown that the conventional correction factors fail to generalize the engine performance variables at high altitudes. An investigation was therefore made at the NACA Lewis laboratory to determine the altitude performance of the J33-A-23 turbojet engine and to demonstrate the magnitude of departure of actual altitude performance from that predicted from sea-level performance."

Report presenting an experimental investigation to determine the combustion properties of several magnesium-hydrocarbon slurry blends and to indicate the feasibility of the application of slurry-type fuels to high-speed aircraft. High-concentration magnesium slurries showed large improvements in combustion stability and tail-pipe-burner net thrust.

This report is a compilation of many of the pertinent research data acquired by the National Advisory Committee for Aeronautics on fuel performance in piston engines. The original data for this compilation are contained in many separate NACA reports which have in the present report been assembled in logical chapters that summarize the main conclusions of the various investigations. Complete details of each investigation are not included in this summary; however, such details may be found, in the original reports cited at the end of each chapter.

Report presents the results of an investigation to determine the equilibrium temperature and heat-transfer coefficients for transverse cylinders in a high-speed stream of rarefied gas measured over a range of Knudsen numbers (ratio of molecular-mean-free path to cylinder diameter) from 0.025 to 11.8 and for Mach numbers from 2.0 to 3.3. The range of free-stream Reynolds numbers was from 0.28 to 203. The models tested were 0.0010-, 0.0050-, 0.030-, 0.051-, 0.080-, and 0.126-inch -diameter cylinders held normal to the stream.

From Summary: "An analysis of the flight time history of a rocket-propelled model of a 60 degree delta-wing airplane configuration, fired for the purpose of obtaining zero-lift drag data, indicated wing flutter and subsequent failure at low-supersonic Mach numbers. This flutter occurred during the unpowered decelerating portion of the flight. The behavior of the model during flight is discussed and the mass and stiffness characteristics of a duplicate wing are presented."

Memorandum presenting a summary of heat-resistant materials obtained from interviews with alloy producers, jet-engine manufacturers, and research laboratories in Britain during October and November 1950. The primary subjects of interest included the properties of materials and service requirements for gas turbines, criteria used for judging and inspecting materials, and research developments of both a practical and fundamental nature in the field.

From Introduction: "The primary purpose of the investigation described in the present described in the present report is to formulate a method which is of value for qualitative calculations of base pressure both on airfoils and bodies."