This report helps determine tritium in the range of 0.1 to 100% in other gases using an ion chamber that is analyzed within this report.

Report describing an investigation conducted with a single combustor from a J47 turbojet engine using weathered aviation gasoline and several spark-plug modifications to determine altitude ignition, acceleration, and steady-state operating characteristics. Results regarding ignition, acceleration, altitude operational limits, combustion efficiency, and pressure loss are provided.

The durability of five different structural or cooling configurations or combination of both of air-cooled blades made of noncritical materials was investigated in a modified turbojet engine. The greater part of the investigation was conducted at an engine speed of 11,500 rpm, a turbine-inlet temperature of approximately 1670 degrees F, and a cooling-air to combustion gas flow ratio per blade of 0.05. The results of the investigation indicated that air-cooled blades made of noncritical metals can be operated for extended periods of time in engines at current inlet temperatures; however, before these blades are considered completely satisfactory for gas-turbine application, some means such as coatings is required to inhibit the oxidation of the blades.

Report presenting a comparison of the transonic aerodynamic characteristics of unswept and 45 degree sweptback wings in the high-speed tunnel and slotted tunnel. The purpose of the investigation was to explore the possibilities and limitations associated with transonic testing of relatively large wings in a rectangular slotted tunnel. Results regarding lift, pitching moments, drag, bending moments, and Schileren photographs are provided.

Time constants that characterize engine speed response of a turbine-propeller engine over the cruising speed range for various values of constant fuel flow and constant blade angle were obtained both from steady-state characteristics and from transient operation. Magnitude of speed response to changes in fuel flow and blade angle was investigated and is presented in the form of gain factors. Results indicate that at any given value of speed in the engine cruising speed range, time constants obtained both from steady-state characteristics and from transient operation agree satisfactorily for any given constant fuel flow, whereas time constants obtained from transient operation exceed time constants obtained from steady-state characteristics by approximately 14 percent for any given blade angle.

Memorandum presenting flight tests conducted on two straight-wing jet airplanes of generally similar configuration, one exhibiting a diving tendency and the other a climbing tendency, in order to investigate the cause for the particular type of behavior of each airplane at high Mach numbers. The results showed that the diving tendency experienced by the one airplane was due to the predominant effect of an increased angle of attack of the horizontal tail.

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.

Report presenting an investigation in the high-speed 7- by 10-foot tunnel through a range of Mach numbers to determine the effects of external-store fineness ratio, store shape, store chordwise position, pylon thickness, pylon length, and pylon sweep angle on the aerodynamic characteristics of a number of underwing pylon-suspended external stores in combination with a 45 degree sweptback semispan wing and fuselage.

Report presenting a wing-body combination with a plane triangular wing of aspect ratio 2 with NACA 0005-63 thickness distribution in streamwise planes, which has been twisted and cambered for a trapezoidal span load distribution at subsonic and supersonic Mach numbers.

Performance of a J47D (RX1-1) turbojet engine equipped with afterburner, variable-area exhaust nozzle, and integrated electronic control was determined over a range of flight conditions. These data were obtained with the electronic control both operative and inoperative. For operation with scheduled exhaust nozzle area, the minimum specific fuel consumption of 1.15 pounds of fuel per hour per pound of net thrust occurred at about 7200 rpm at altitudes from 5000 to 25,000 feet at a flight Mach number of 0.19.

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.

From Summary: "Experimental force, moment, and center-of-pressure variations for a large number of bodies of revolution have been compared with the calculated characteristics based on the approximate theory developed in NACA-RM-A9I26. The bodies varied in fineness ratio from 4.5 to 21.1, from blunt unboattailed bodies to airship hulls, and the experimental results are given for widely varying Mach number ranges of angle of attack. It is shown that the lift and drag characteristics are fairly accurately predicted by the theory but that the actual center of pressure is more rearward than the theory indicates."

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.

Memorandum presenting pressure distributions on two wing-body combinations obtained at a Mach number of 1.9 to investigate the wing-body interference. A rectangular wing, a triangular wing, and a cylindrical body with an ogive nose were studied alone and in combination. The pressure distributions over the wing-body combination compared favorably with theoretical calculations based primarily on a generalization of the method of Nielsen and Matteson, except at the root section of the wings where the boundary layer of the body modified the flow.

Report presenting testing of two two-blade propellers in the 8-foot high-speed tunnel for a range of blade angles and Mach numbers. The results show that changes in thrust loading due to compressibility effects were much smaller for the thin-blade propeller than for the thick-blade propeller.

A wind tunnel investigation has been conducted to determine the steady-state windmilling and engine speed decay characteristics of the J34-WE-32 turbo-jet over a range of altitudes from 5000 to 50,000 feet and simulated flight Mach numbers from 0.19 to 1.06. The effect of an engine accessory load on the speed decay characteristics was also determined. The accessory load was about 7.8 horsepower for engine speeds above 4000 rpm and decreased with decreasing engine speed. An analysis of the speed decay data was made and engine speed decay rates were determined for hypothetical accessory loads up to 40 horsepower.

A spark energy of 2.13 joules per spark at 1 spark per second produced ignition to an altitude of 50,000 feet at a flight Mach number of 0.6. The minimum power requirements for ignition were obtained from a combination of low spark repetition rates and high spark energy. The altitude-ignition limit was also increased by increasing spark-gap immersion, fuel temperature, inlet-air temperature, and fuel volatility, and by decreasing flight Mach number. The maximum altitude at which flame propagation was accomplished from combusters with spark plugs to combusters without spark plugs to combustors without spark plugs was increased about 5000 feet by increasing fuel volatility.

"A multiple-range potentiometer circuit is described that provides automatic measurement of temperatures or temperature differences with any one of several thermocouple-material pairs. Techniques of automatic reference junction compensation, span adjustment, and zero suppression are described that permit rapid selection of range and wire material, without the necessity for restandardization, by setting of two external tap switches" (p. 1).

An investigation was made of the variation of the pressure limits of flame propagation with tube diameter for quiescent propane with tube diameter for quiescent propane-air mixtures. Pressure limits were measured in glass tubes of six different inside diameters, with a precise apparatus. Critical diameters for flame propagation were calculated and the effect of pressure was determined. The critical diameters depended on the pressure to the -0.97 power for stoichiometric mixtures. The pressure dependence decreased with decreasing propane concentration. Critical diameters were related to quenching distance, flame speeds, and minimum ignition energy.

Report presenting an investigation to compare the characteristics of a full-span and a semispan highly swept wing in order to evaluate the general validity of the semispan wing testing technique. Results regarding the lift, drag, and pitching-moment characteristics are provided.

"An experimental investigation of the aerodynamics of a slender cone-cylinder body of revolution was conducted at a Mach number of 3.85 for angles of attack of 0 degree to 10 degrees and a Reynolds number of 3.85x10(exp 6). Boundary-layer measurements at zero angle of attack are compared with the compressible-flow formulations for predicting laminar boundary-layer characteristics. Comparison of experimental pressure and force values with theoretical values showed relatively good agreement for small angles of attack. The measured mean skin-friction coefficients agreed well with theoretical values obtained for laminar flow over cones" (p. 1).

Report presenting the results of a wind-tunnel investigation to determine the control effectiveness and variations of forces and moments as functions of angles of attack and sideslip for a scale model of the MX-775A missile at a range of Mach and Reynolds numbers. Results regarding the static longitudinal stability and control characteristics, Reynolds number effects, lateral-control characteristics, and clipped-wing configuration characteristics are provided.

Memorandum presenting an investigation of the effect on load-range performance of various combinations of compressor pressure ratio and turbine-inlet temperature for the turbine-propeller engine and to provide a means for comparing the load range of turbine-propeller and turbojet engines for a range of flight speeds.

Report presenting an investigation to determine the effects of a simplified form of boundary-layer control on the low-speed longitudinal characteristics of a sweptback wing. The primary objective was to improve the longitudinal characteristics of the sweptback wing at lift coefficients below the maximum. Results regarding the characteristics of the wing without boundary-layer control and effects of boundary-layer control are provided.