Report presenting a flight investigation to determine the comparative performance of AN-F-58 and AN-F-32 fuels in a 4000-pound-thrust turbojet engine. The fuels were equivalent over the range of conditions investigated. Results regarding corrected net thrust, corrected jet-fuel consumption, variation of corrected tail-pipe temperature, combustor blow-out speeds, and visual observations of the jet exhaust are provided.

Note presenting pressure distribution measurements made on the wing of a fighter-type airplane to determine the span loading and to compare center-of-pressure results with those obtained by strain-gage measurements on the same airplane during a previous flight investigation. Flight tests were all made at a pressure altitude of about 30,000 feet and covered a Mach number range from approximately 0.35 to 0.81. Results regarding additional air load, spanwise center of pressure of additional air load, basic air load distribution, and span loading during a stall and buffeting are provided.

Report presenting a discussion of the aerodynamic forces and moments on inclined bodies of revolution. An approximate theory to allow for the effects of viscosity is developed and applied. Results regarding the variation of lift and pitching moment, and center of gravity are provided.

Report presenting pressure distributions of three triangular wing models: a wing-alone model, the same wing combined with a body, and a mock-up of a triangular-wing airplane. Results regarding the separation-vortex air flow over triangular wings, general comments regarding the applicability of the study, chordwise pressure distribution, section lift characteristics, center of pressure, and span load distribution are provided.

Report presenting an investigation to determine the aerodynamic characteristics in sideslip of a triangular wing of aspect ratio 2.04 in combination with a body of fineness ratio 12.5 and a vertical tail surface. The body combined with the triangular plan-form wing caused no significant changes in the lift characteristics of the wing and only a 1-percent decrease in the static margin. Results regarding the longitudinal characteristics, lateral and directional characteristics, and estimation of tail and rudder effectiveness are provided.

Report presenting an altitude-chamber investigation to determine the altitude performance characteristics of the British Rolls-Royce Nene II turbojet engine with an 18.41-inch-diameter jet nozzles. Testing occurred at a range of simulated altitudes and ram-pressure ratios. Results regarding the simulated flight performance, generalized performance, and effect of jet-nozzle area on performance are provided.

"The flexural vibration of a rotating propeller blade with clamped shank is analyzed with the object of presenting, in matrix form, equations for the elastic bending moments in forced vibration resulting from aerodynamic forces applied at a fixed multiple of rotational speed. Matrix equations are also derived which define the critical speeds end mode shapes for any excitation order and the relation between critical speed and blade angle. Reference is given to standard works on the numerical solution of matrix equations of the forms derived" (p. 1).

"High-speed wind-tunnel tests were conducted of two versions of a 0.17-scale model of the McDonnell XF2H-1 airplane to ascertain the high-speed stability and control characteristics and to study means for raising the high-speed buffet limit of the airplane, The results for the revised model, employing a thinner wing and tail than the original model, revealed a mild diving tendency from 0.75 to 0.80 Mach number, followed by a marked climbing tendency from 0.80 to 0.875 Mach number. The high-speed climbing tendency was caused principally by the pitching-moment characteristics of the wing" (p. 1).

Report presenting an investigation of the flutter of a small one-blade wooden propeller with a Clark Y section. The highest flutter speeds were found in the vicinity of the angle of zero aerodynamic moment, with flutter speed increasing in this region with decreasing pressure.

Memorandum presenting an investigation conducted to evaluate the effectiveness of a simple internal regenerative fuel preheater for a 20-inch-diameter ram jet. Data obtained at subsonic sea-level conditions indicated that fuel could be successfully preheated in this manner.

Report presenting an application of the linearized supersonic flow theory to the calculation of the camber and twist required for various lift distributions on a triangular wing with leading edges behind the Mach cone. Several specific examples are used and plots of the cambered surfaces, corresponding lift distributions, and values of the theoretical drag coefficients are presented.

From Introduction: "Recent investigations have indicated several wing plan forms, wing sections, and wing-body-tail combinations suitable for flight at supersonic speeds. One such lifting surface, a thin, sharp-edged without sweep of aspect ratio 4 and taper ratio 0.5, has been the subject of an investigation in the Ames 12-foot pressure wind tunnel. The aim of the investigation was to determine the aerodynamic characteristics of such a wing plan form throughout the range of subsonic Mach numbers up to 0.94."

Memorandum presenting measurements of some of the high-speed characteristics of the D-558-1 airplane up to Mach number 0.89. The results of the tests showed that the stabilizer incidence drastically affected the longitudinal trim characteristics above a Mach number of 0.80.

Report discussing tests of a scale model of the XB-51 airplane to determine its force, stability, and control characteristics in pitch and yaw at various Mach numbers. The effects of the dive breaks and the bomb bay are also described.

Report presenting an altitude-chamber investigation to determine the altitude performance characteristics of the British Rolls-Royce Nene II turbojet engine with a standard 18.75-inch-diameter jet nozzle. Results regarding the simulated flight performance and generalized performance across other altitude and pressure characteristics are provided.

Note presenting a theory of plasticity based on the concept of slip as proposed for the relationship between stress and strain for initially isotropic materials in the strain-hardening range. The theory is an extension to polyaxial stress conditions of the conventional uniaxial stress-strain relation, and time-dependent effects, such as creep and stress relaxation, are not considered.

Memorandum describing preliminary investigations of two 3-inch-diameter slotted test sections over a range of pressure ratios from 1.3 to 10.0. The two test sections varied based on the number of slots and amount of open space, but they showed no appreciable difference in performance. Results regarding the slots with no chamber around the test section and with a closed chamber around the test section are provided.

Report presenting an investigation of the low-speed, power-off static longitudinal stability and control characteristics of a canard model with a triangular wing and horizontal tail in the free-flight tunnel. Results regarding the horizontal tail used to overcome change in stability and horizontal tail used for longitudinal control are provided.

"As part of the performance investigation of compressors for the J33 turbojet engine, the A-21 model and the A-23 model with a 17- and a 34-blade impeller were operated with water injection at their respective design equivalent speeds of 11,500 and 11,750 rpm. Inlet conditions of pressure of 14 inches of mercury absolute and of ambient temperature correspond to those of the investigation of these models without water injection. The water-air ratio by weight ranged from 0.05 to 0.06. By the use of water injection, the peak pressure ratio of the A-21 compressor and the A-23 compressor with a 34-blade impeller increased approximately 0.38, whereas that of the A-23 compressor with a 17-blade impeller increased only 0.14" (p. 1).

Contains results of calculations made to determine the neutral oscillatory stability boundaries, period and time to damp of the oscillatory mode, and motions following disturbances. The calculations were made for Mach numbers of 0.75 and 2.3 at an attitude of 35,000 feet and for the landing condition at sea level.

Note presenting the method of numerical integration for calculation of beam deflection in matrix form to give it the advantages which are inherent in an influence-coefficient method. Examples are presented to show that the use of weighted matrices reduces the calculation time required to obtain a desired degree of accuracy.

"An investigation was conducted to determine the effect of turbine-disk cooling with air on the efficiency and the power output of the radial-flow turbine from the Turbo Engineering Corporation TT13-18 turbosupercharger. The turbine was operated at a constant range of ratios of turbine-inlet total pressure to turbine-outlet static pressure of 1,5 and 2.0, turbine-inlet total pressure of 30 inches mercury absolute, turbine-inlet total temperature of 12000 to 20000 R, and rotor speeds of 6000 to 22,000 rpm, Over the normal operating range of the turbine, varying the corrected cooling-air weight flow from approximately 0,30 to 0.75 pound per second produced no measurable effect on the corrected turbine shaft horsepower or the turbine shaft adiabatic efficiency" (p. 1).

A spin-recovery investigation has been conducted in the Langley 20-foot free-spinning tunnel on a 20-scale model modified to represent the McDonnell XF2H-1 airplane. The project included tests both with tip tanks installed and with the tanks removed. The results indicated that the recovery characteristics of the airplane would be satisfactory for all loadings by normal recovery technique (full reversal of the rudder, followed 1/2 turn later by movement of the elevator down). The rudder pedal and the elevator stick forces likely to be encountered in a spin should be within the capabilities of the pilot.

"The spin and recovery characteristics of the Northrop XF-89 airplane, as well as the spin-recovery parachute requirements, the control forces that would be encountered in the spin, and the best method for the crew to attempt an emergency escape are presented in this report. The characteristics were mainly estimated rather than determined by model tests because the XF-89 dimensional and mass characteristics were such as to make this airplane similar to several others, models of which have previously been tested. Brief tests were made on an available model of similar design to augment the estimation" (p. 1).