Report presenting an investigation to obtain the pressure distribution over a sharp-nose body of revolution with a circular-arc profile and fineness ratio 6 at transonic speeds using the NACA wing-flow method. Results regarding the variation of pressure coefficient with Mach number, pressure distributions along the body axis, pressure drag, and effects of interference and horizontal gradient are provided.

Report presenting testing of a 4.5 inch by 4.5 inch tunnel with slots in two opposite walls in order to determine the effects of various slot exit shapes, mixing sections, and diffusers on power requirements. Some of the data obtained included measurements of the pressure ratio required to operate the tunnel, the effects of auxiliary bleed flow, diffuser static-pressure ratios and distributions, and diffuser total pressure distributions.

Memorandum compiling summaries from NACA reports on fuel that were published between July 1945 and 1952. The summaries are intended to be detailed enough to eliminate the need to obtain the complete report.

Operating characteristics of the 11-stage 4000-pound-thrust axial-flow turbojet engine were determined. A standard compressor and a compressor with the blade angles of the rotor and stator blades increased 5 degrees to obtain greater air flow, were investigated.

Report presenting a study and experimental investigation on the pressure rise across shock waves required to cause separation of the boundary layer on a flat plate. The interaction of shock wave and boundary layer was investigated experimentally when the boundary layer was caused to separate from the surface of a tube. Results regarding testing and correlation with other results are provided.

The sea-level performance of I-16 turbojet engine at zero ram was investigated to determine the effects of an intake duct, shroud, and tail pipe intended for installation in an XFR-1 airplane. Engine speeds ranged from 8000 to 16,500 rpm for several variations of the intake duct and tail pipes.

From Introduction: "Range in more or less steady level flight depends directly on aerodynamic lift-drag ratio at high supersonic speeds, just as it does at lower speeds. This result follows from the classical Breguet range equation in the case of powered flight, and it may be easily deduced from the equations of motion for unpowered or gliding flight (see refs. 1 and 2)."

Report presenting an investigation to determine the effects of inlet-annulus blockage on compressor performance and its corresponding effect on the computed performance of a hypothetical engine. The hypothetical engine performance was calculated from the overall compressor performance and assumed component performance characteristics. Results regarding the compressor performance with no inlet blockage, effect of hub blockage on compressor performance and stall characteristics, effect of sector blockage on compressor performance, effect of hub blockage on computed engine performance, and design and control problems are provided.

Memorandum presenting the subsonic and transonic longitudinal handling qualities of the Douglas D-558-II research airplane with several wing modifications designed to alleviate swept-wing instability and pitch-up. The airplane configurations investigated included the basic wing configuration and two wing-fence configurations in combination with retracted, free-floating, or extended slat,s and a wing leading-edge chord-extension configuration.

Memorandum presenting a flight investigation to determine the longitudinal and lateral handling qualities of the Douglas X-3 research airplane in the clean configuration. Static and dynamic stability and control characteristics were determined during trimmed and maneuvering flight at an average altitude of 30,000 feet and over a Mach number range from 0.7 to 1.16.

Report summarizing several experimental tail-pipe-burner investigations to indicate the effects of tail-pipe-burner design variables on the performance and operating characteristics. Most of the configurations were investigated over a wide range of altitudes and flight Mach numbers. The results indicate the desirable design features of a tail-pipe burner that will operate with high combustion efficiency and exhaust-gas temperature up to an altitude of approximately 50,000 feet.

A wind tunnel investigation was conducted to determine the performance of a 4000-pound-thrust axial-flow turbojet engine with a high flow compressor. Pressure altitudes included 5000 to 40000 feet with ram pressure ratios from 1.00 to 1.82. Altitudes included 20000 to 40000 feet and ram pressure ratios from 1.09 to 1.75. A comparison is made between engine performance with high flow and low flow compressors.

The gust and draft velocities from records of NACA instruments installed in P-61C airplanes participating in thunderstorm flights at Clinton County Army Air Field, Ohio, from August 16, 1947 to August 20, 1947 are presented.

The gust and draft velocities from records of NACA instruments installed in P-61C airplanes participating in thunderstorm flights at Clinton County Army Air Field, Ohio, from September 10, 1947 to September 15, 1947, are presented.

Report presenting the flight-determined buffet boundaries of ten airplanes. Comparisons are made with five possible buffeting criteria related to airfoil-section characteristics. The primary factors that determine buffeting criteria are critical Mach number, Mach number of sonic flow at the crest, lift-divergence Mach number, lift-peak Mach number, and empirical buffeting criterion are provided.

From Summary: "The results of an experimental investigation of an NACA submerged-air-inlet system on a 1/5-scale model of a fighter airplane are presented. Preliminary development tests were conducted to select the optimum entrance configuration. Duct-system total-pressure losses and pressure distributions over the lip and ramp of this air intake were obtained."

The characteristics of a wedge static-pressure sensing element with various holder configurations were determined and compared with the characteristics of the conventional tube. The probes were tested over a range of Mach number from 0.3 to 0.95 and at various pitch and yaw angles. The investigation showed that the spike-mounted wedge sensing element has a pressure coefficient comparable with the conventional subsonic static-pressure probe and the pressure coefficient of the wedge varied less than that of the conventional probe for corresponding change of yaw angle.

From Introduction: "The purpose of the present paper is to investigate the effect of two-speed gearing on the take-off efficiency under certain conditions. The present paper gives charts from which the efficiencies can be readily computed for optimum rotational speeds. Also included is a brief discussion of the static thrust of thin propellers, including the effect of camber on the static thrust."

"Wind-tunnel tests were conducted to determine the longitudinal stability characteristics of a full-scale Northrop XSSM-A-3 missile. Various wing modifications were investigated in an effort to provide a configuration that would maintain longitudinal stability to lift coefficients necessary for landing the missile during flight tests. The results of the tests led to the choice of a wing with an increased leading-edge radius" (p. 1).

"A two-dimensional inlet-guide-vane cascade was investigated to determine the effects of ice formations on the pressure losses across the guide vanes and to evaluate the heated gas flow and temperature required to prevent Icing at various conditions. A gas flow of approximately 0.4 percent of the inlet-air flow was necessary for anti-icing a hollow guide-vane stage at an inlet-gas temperature of 500 F under the following icing conditions: air velocity, 280 miles per hour; water content, 0.9 gram per cubic meter; and Inlet-air static temperature, 00 F. Also presented are the anti-icing gas flows required with modifications of the hollow Internal gas passage, which show heat input savings greater than 50 percent" (p. 1).

Report discussing testing to determine the aerodynamic characteristics of two semispan delta-wing configurations. Information about the lift characteristics, drag characteristics, pitching-moment characteristics, and comparison with other results is provided.

"Free-flight drag measurements are presented which show the practicability of duplicating the zero-lift drag rise of many airplane configurations by simple bodies of revolution. The results confirm the transonic area rule for straight wings, and for delta and modified-delta wings with and without nacelles. The results showed that the area rule did not apply to one swept-wing configuration and an explanation is advanced to explain why it does not apply" (p. 1).

Report presenting an investigation in the high speed 7- by 10-foot tunnel through a range of Mach numbers to determine the lateral-control and hinge-moment characteristics of a spoiler-slot-deflector configuration on a semispan 35 degree sweptback-wing model. The results indicated that the spoiler-slot-deflector configuration with the ratio of deflector projection to spoiler projection increasing with increasing control projection has good rolling-moment effectiveness throughout the angle of attack range and throughout the high subsonic speed range.

"Flutter models of the upper and lower vertical tails of an air-to-ground missile have been tested in the Mach number range from 0.5 to 3.0. It was found that the upper surface exhibited more or less conventional flutter behavior throughout the Mach number range, whereas the lower surface experienced a sudden change in flutter mode at a Mach number of about 1.18. This change in flutter mode was accompanied by a decrease of about 50 percent in the density required for flutter to occur" (p. 1).