Report presenting an investigation of the performance of pentaborane fuel in a flight-type, 9.75-inch-diameter ramjet engine mounted in a connected-pipe altitude facility. Combustor efficiency was above 85 percent throughout the range of test conditions. Results regarding the connected-pipe performance and estimated flight performance are provided.

Report presenting results of testing of a rocket model with cruciform 60 degree triangular wings in continuous rough air at transonic speeds. The wing arrangement tested appears to be useful for improving the accuracy of the results. Results regarding the characteristics of the rough-air response, variation of acceleration with Mach number, and evaluation of the cruciform arrangement are provided.

Report presenting experimental force and moment data for rectangular wings of aspect ratios 1, 2, and 3 at a range of angles of attack and Mach numbers. Shock-expansion theory was found to adequately predict the span load distribution in the two-dimensional flow region below the shock-detachment angle. Results regarding basic physical data, the attached regime, and the detached regime are provided.

From Summary: "A preliminary experimental study of symmetrical, circular, internal compression inlets has shown that they attain pressure recovery equal to that measured by conical nose inlets at Mach numbers up to about 2.3. This pressure recovery was obtained with configurations having essentially zero pressure drag of the external surfaces."

Report presenting tables and charts of gas properties for use in thermodynamic calculations for engine cycles involving the combustion of air and any fuel or combustion of fuels containing carbon, boron, hydrogen, and oxygen. Dissociation and phase changes may be accounted for with the method presented, which does not require the presentation of separate data for each fuel-air ratio.

Report presenting a low-speed investigation to determine the static and damping derivatives of a 60 degree delta wing, a 45 degree swept wing, and an unswept wing from 0 to 90 degrees angle of attack. Results regarding the static longitudinal stability characteristics, static lateral stability characteristics, damping characteristics.

Report presenting an investigation of the effectiveness and loading characteristics of an aileron mounted on an unswept-wing-body configuration. A flap-type outboard aileron was tested with and without paddle balances at a range of Mach numbers and angles of attack. The aileron effectiveness, hinge-moment parameter, and effect of the paddle balances are presented.

Report presenting an investigation to determine the aerodynamic characteristics of bodies with elliptical and triangular cross sections and to compare the data with a body with circular cross sections. Force tests to determine lift, drag, and pitching-moment characteristics as well as pressure-distribution measurements were made for an angle of attack range.

Report presenting a study of four short annular diffusers with different diffuser passage area variations and with various combinations of straightening vanes, vortex generators, splitters, and boundary layer suction for flow control. Results regarding turbine discharge whirl, diffuser passage modification, and boundary layer control are provided.

The thermal decomposition of ethylpentaborane at temperatures of 185 degrees to 244 degrees C is approximately a 1.5-order reaction. The products of the decomposition were hydrogen, methane, a nonvolatile boron hydride, and traces of decaborane. Measurements of the rate of decomposition of pentaborane showed that ethylpentaborane has a greater rate of decomposition than pentaborane.

Report presenting some methods providing sizable reductions in drag for aspect ratios of current interest. The drag savings are maintained over a wide Mach number range, particularly for low-aspect-ratio wings. A significant part of the drag reduction is found to be due to the nonaxisymmetric distortion.

Report presenting the average heat-transfer to the forward half of a circular cylinder measured in a blowdown jet at a stream Mach number of 4.15. Most of the tests was made at a wall-to-stagnation temperature ratio of about 0.8. Report presenting pressure distributions, heat transfer and recovery temperatures, and effect of yaw on transition are provided.

During a free-jet investigation of a 28-inch ram-jet engine at a Mach number of 2.35, flow pulsation at the engine inlet were discovered which proved to have an effect on the engine performance and operational characteristics, particularly the engine rich blowout limits. This report discusses the finding of the flow pulsations, their elimination, and effect. Other facility characteristics, such as the establishment of flow simulation and the degree of subcritical operation of the diffuser, are also explained.

From Summary: "Thrust augmentation of an axial-flow type turbojet engine by burning fuel in the tail pipe has been investigated in the NACA Cleveland altitude wind tunnel. The performance was determined over a range of simulated flight conditions and tail-pipe fuel flows. The engine tail pipe was modified for the investigation to reduce the gas velocity at the inlet of the tail-pipe combustion chamber and to provide an adequate seat for the flame; four such modifications were investigated."

Report presenting an investigation of a four-blade single-rotation propeller in combination with an NACA 1-series D-type spinner-cowling combination at Mach numbers up to 0.83. Characteristics of the propeller operating in the presence of the cowling are compared with the characteristics of the propeller with the spinner.

A brief investigation of a target-type thrust reverser on a single-engine fighter model has been conducted in the Langley 16-foot transonic tunnel at Mach numbers from 0.20 to 1.05. At Mach numbers of 0.80, 0.92, and 1.05, a hydrogen peroxide turbojet-engine simulator was operated with the thrust reverser extended. The angle of attack was varied from 0 degrees to 5 degrees at these Mach numbers.

Memorandum presenting an investigation in which the behavior of parachutes in close proximity to one another was studied by using small parachutes attached to thin wires in the 20-foot free-spinning tunnel. The results indicate that the parachutes, when side by side, generally had little effect on one another and may sometimes have had slight repelling effects.

"Spin tests have been conducted in the Langley free-spinning tunnel on a 1/16-scale model of the McDonnell XP-85 airplane with the normal X-tail replaced with a short-coupled conventional tail arrangement. The effect of the conventional tail arrangement and the effects of various modifications upon the spin and recovery characteristics of the model were determined. The results of the tests indicated that installation of the conventional tail arrangement will not provide satisfactory recoveries from spins of the airplane" (p. 1).

Memorandum presenting an investigation utilizing a 1/15-scale rocket-propelled model of the Convair B-58 supersonic bomber. The drag at model trim lift was obtained at a range of Mach and Reynolds numbers. A comparison of the drag at transonic speeds and approximately the same Reynolds number showed excellent agreement.

Report presenting tests of four 7.5 degree boattail bodies of revolution with secondary air scoops in free flight to find the change in drag coefficient when a simulated turbojet exhaust issued from conical short-length ejectors. Results indicated that the jet-on total drag coefficients were lower throughout the test Mach number range than corresponding jet-off values of the forebody drag coefficient. Results regarding drag and ejector-shroud characteristics are provided.

Memorandum presenting an investigation of the thermal stability of a commercial grade of propyl pentaborane (HEF-2) at temperatures of 147 and 190 degrees Celsius. The products of decomposition are hydrogen, hydrocarbons, and a solid nonvolatile yellow boron hydride. An equation is provided that can be used to calculate the approximate time required to decompose 20 percent of propyl pentaborane at other temperatures.

"Low Mach number longitudinal-stability and control characteristics as predicted by use of wind tunnel data from a powered 3/16-scale model are compared with flight test measurements of a Navy BTD-1 airplane. The accuracy of the wind tunnel data and the discrepancies involved in attempting to correlate with flight data are discussed and analyzed. The comparison showed that wind tunnel predictions were, in general, in good agreement with flight test data" (p. 1).

Memorandum presenting a limited investigation in the supersonic pressure tunnel to determine the effectiveness of differential horizontal-tail deflection for producing lateral control for two swept-wing airplane models in the Mach number range from 1.4 to 2.0. The tests were limited to small tail deflections but included combined angles of attack and sideslip up to about 20 degrees. The tests showed the rolling-moment effectiveness to be essentially constant with sideslip angle but to decrease with increasing angle of attack.

Report presenting the effect of free-stream Reynolds number, engine installation, and model scale on inlet stability limits and on the amplitude and frequency of buzz. The data was obtained at mach number 2.0 and a range of angles of attack. Results regarding the free-stream Reynolds number effect, model scale, and effect of engine on stability are provided.