Report presenting a study of the acceleration characteristics of a turbojet engine equipped with variable-position inlet guide vanes in the altitude test chamber. Maximum acceleration values for 3 engines of the same model were also obtained during testing and were found to differ as much as 50 percent. Results regarding the effect of fuel step size and inlet guide vane on acceleration, effect of flight condition, reproducibility of engine acceleration, compressor pressure ratio in relation to acceleration, and acceleration with inlet air distortion are provided.

Report discussing testing of a scale model of the Convair F-102B to determine its aerodynamic characteristics at several Mach numbers. Four basic body modifications and two afterbody configurations were evaluated.The body modifications were all found to slightly reduce values of minimum drag, but did not cause a change in the static stability and lift-curve-slope values compared to the F-102A.

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.

From Summary: "A preliminary investigation of the effects of changes in the elevator and rudder settings and of small changes in attitude upon the aerodynamic forces and moments exerted upon a spinning airplane was undertaken with the spinning balance in the 5-foot vertical tunnel of the National Advisory Committee for Aeronautics. The tests were made on a 1/12-scale model of the "NY-1" airplane. Data by which to fix the attitude, the radius of spin, and the rotational and air velocities were taken from recorded spins of the full-scale airplane."

Report presenting an investigation to determine the effects of a vertical tail with the leading edge swept back 63 degrees on the aerodynamic characteristics of a wing-fuselage combination with a wing with the leading edge swept back 63 degrees. The aerodynamic characteristics in sideslip with and without the vertical tail are also presented. Results regarding the directional stability, rudder effectiveness, and rudder hinge moments are described.

From Summary: "Results of wind-tunnel tests are presented for a wing with the leading edge swept back 63^o and of symmetrical section in combination with a body at Mach numbers from 0.5 to 0.95 and from 1.09 to 1.51."

Report presents the results of a study made to determine the air-flow characteristics around finned cylinders. Air-flow distribution is given for a smooth cylinder, for a finned cylinder having several fin spacings and fin widths, and for a cylinder with several types of baffle with various entrance and exit shapes. The results of these tests show: that flow characteristics around a cylinder are not so critical to changes in fin width as they are to fin spacing; that the entrance of the baffle has a marked influence on its efficiency; that properly designed baffles increase the air flow over the rear of the cylinder; and that these tests check those of heat-transfer tests in the choice of the best baffle.

From Introduction: "This report presents the results of an analysis to determine the coolant flow and pressure requirements for a particular return-flow turbine rooter blade design utilizing hydrogen, helium, or air as the coolant."

From Introduction: "V-g records supplied the NACA by the Bureau of Aeronautics in 1948 and 1949 have provided additional material. These records are analyzed statistically in this report to the frequency of large values of acceleration and airspeed, and results are compared with the design requirements."

From Introduction: "This paper presents results of an analysis of shear, bending-moment, and torque loads measured on the vertical tail during rudder-step, rudder-pulse, aileron-roll, and steady-sideslip maneuvers. In order to assess effects of Mach number and altitude, the maneuvers were performed at altitudes of 15,000, 25,000, and 35,000 feet and Mach numbers from 0.49 to 0.82."

Report presenting an analysis made to permit a comparative evaluation of the turbine rotor cooling-air requirements with convection-cooled blades for four combustor-outlet radial gas-temperature profiles: a uniform profile, a profile representable by a complete cycle of the cosine wave using cooler gas layers near the turbine casing, a profile representable by one-half cycle of the cosine wave using cooler gas layers near the stator inner ring, and an optimum profile resulting in the absolute minimum cooling-air requirements.

Report presenting boundary-layer measurements on rocket-powered free-flight models to determine average skin-friction coefficients. The test body, NACA RM-10, was a fin-stabilized parabolic body of revolution of fineness ratio 12.2 with a blunt base to provide space for a rocket jet. Results regarding the skin-friction and boundary-layer profiles and experimental and theoretical curves are provided.

Report presenting a friction, wear, and endurance-lift study made with bonded films of mixed oxides containing lead monoxide (PbO) as the main component. The coatings lubricated over the entire temperature range, but were far more effective from 500 to 1250 degrees Fahrenheit than at the lower temperatures. Results regarding the effect of silica additions on coating formation, determination of coating composition, effect of coating thickness on friction and wear, effect of temperature on friction and wear, and endurance properties are provided.

Memorandum presenting a single J33 combustor and an experimental tubular combustor incorporating a fuel vaporizer as operated with gaseous hydrogen at temperatures slightly above the boiling point of the fuel. Data were obtained to explore possible effects of the fuel temperature on combustor performance and on the control and measurement of fuel flow.

Report presenting a method for calculating the path of a jettisonable nose section at any speed by means of successive approximations using static aerodynamic characteristics. Conditions for consideration, including the effect of stabilizing fins, are included in the calculations.

Report presenting an attempt to determine the reliability and calibration of the Langley transonic tunnel in the open slotted test section. Results regarding test-section calibration, including flow uniformity, calibration, and angularity, model testing and boundary interference, and reduction of interference are provided.

Report presenting five fuels of boiling temperatures and several hydrocarbon types in a jet-propulsion annular combustor to determine the effect of fuel boiling temperature and paraffinic and aromatic hydrocarbon types on combustion efficiency and altitude operational limit. At the severe inlet-air condition, the highest combustion efficiencies were obtained with the paraffinic and aromatic fuels with low boiling temperatures were found to vary from 30 to 58 percent.

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.

Report presenting a comparison of normal load factors measured during combat operations with those measured during an NACA flight program conducted with fully instrumented service airplanes in operational training. Results indicated that for an equal number of maneuvers, normal load factors obtained from the NACA program are greater than those obtained during combat when based on the service-limit load factor.

Report presenting an investigation to determine the lift, drag, and pitching-moment characteristics of the NACA 0010 and 0010-64 airfoil sections at Mach numbers up to 0.91 and for a range of Reynolds numbers.

Report presenting an investigation of an 18-foot-radius helicopter rotor powered by tip-mounted ramjet engines in the helicopter test tower. The engine performance is compared with the performance determined in a previous investigation of a 9-foot-radius rotor with the same engines at similar speeds but with twice the centrifugal forces. Results regarding the propulsive characteristics, minimum specific fuel consumption and corresponding propulsive thrust, and operational characteristics are provided.

Report presenting a comparison of the performance of a German Jumo 004 can-type combustor and the performance of two contemporary United States turbojet combustors to determine whether the Jumo 004 was more advanced and to determine whether there are basic, inherent differences in the performance achieved with the can or annular combustor type. Results regarding altitude operational limits, combustion efficiency, pressure loss, and temperature profile at combustor outlet are provided.

Memorandum presenting a force-test investigation to determine whether the static stability characteristics of a twisted and cambered 68.7 degree delta wing could be approximated by a plane wing of similar plan form with dihedral. Results regarding longitudinal characteristics and lateral characteristics are provided.

Report presenting a wind-tunnel investigation of a semispan delta wing with the leading-edge swept back 60 degrees. A half-delta control surface was used and testing was performed with and without fences. Results regarding the rolling effectiveness, wing characteristics, and control-surface characteristics are provided.