Report presenting the combustion efficiencies of 10 experimental jet-propulsion fuels that are approximately 200 degrees Fahrenheit cuts of five selected crudes available in large quantities in a turbojet engine combustor at altitude conditions.

This report covers progress in chemical and spectrographic analysis, chemical work, beta-counting methods of analysis, and ore-dressing and pyrometallurgical studies.

Memorandum presenting an investigation of the effect of fuel composition and boiling point on the performance of the type of I-16 jet-propulsion engine. Testing occurred with 14 fuels embodying different types of hydrocarbon and with a range of boiling points. The results indicated that fuel composition and boiling range have a negligible effect on engine thrust, rotor speed, and gas temperatures for the principal types of hydrocarbon fuel when used for short periods of time.

Report presenting a study of the effect of fuel properties on carbon deposition in jet-propulsion engine combustors using seven fuels: kerosene, Diesel fuel oil, toluene, xylene, 62-octane gasoline, a commercial solvent, and AN-F-32 (JP-1) in an I-16 engine at static sea-level conditions and constant rotor speed. Results regarding the reproducibility of data, reduced exhaust-jet-nozzle area, and fuel comparison are provided.

An analysis has been made of the characteristics of several cooling cycles suitable for cockpit cooling of supersonic aircraft. All the cycles considered utilize the difference between dynamic and ambient static pressure to actuate the cooling system and require no additional power source. The results of the study indicate that as flight speeds become greater, increasingly complex systems are required to reduce the altitudes above approximately 35,000 feet, a system composed of an externally loaded expansion turbine in conjunction with a supersonic diffuser would maintain tolerable ventilating air temperature, at least up to a flight Mach number of 2. The most complex system considered,composed of compressor, intercooler, and expansion turbine with the intercooler cooling air decreased in temperature by expansion through an auxiliary turbine is capable of maintaining a ventilation air temperature less than ambient temperature up to a flight Mach number of 3.7.

An investigation has been conducted in the Cleveland 18- by 18-inch supersonic tunnel at a Mach number of 1.85 and angles of attack from 0 deg to 5 deg to determine optimum design configurations for a convergent-divergent type of supersonic diffuser with a subsonic diffuser of 5 deg included divergence angle. Total pressure recoveries in excess of theoretical recovery across a normal shock at a free-stream Mach number of 1.85 wore obtained with several configurations.

Report presenting an investigation in the two-dimensional low-turbulence tunnels to develop optimum double-slotted-flap configurations for seven thin NACA airfoil sections. Each was equipped with the same flaps and measured at the same Reynolds numbers. Results regarding the lift characteristics and pitching moment are provided.

"Investigations were conducted in the Cleveland altitude wind tunnel to determine the performance and operational characteristics of the 19B-2, 19B-8, and 19XS-1 turbojet engines. One objective was to determine the effect of altitude, flight Mach number, and tail-pipe-nozzle area on the performance characteristics of the six-stage and ten-stage axial-flow compressors of the 19B-8 and 19XB-1 engines, respectively, The data were obtained over a range of simulated altitudes and flight Mach numbers" (p. 1).

The test of March 7, 1947 was planned as a check on power coefficient values; however, an analysis of reactivity data gave evidence of a considerable flattening of ``A`` rod in the region between 0--75 inches out. A second test of longer duration was therefore made on April 1, 1947 in order to obtain a check calibration of this portion of the control rod. The results of this test verified the flattening of this portion of ``A`` rod. The redetermined power coefficients based on new rod calibrations are given.

Report presenting the results of pressure-distribution tests to determine the effects of compressibility on the characteristics of the NACA 66,2-215, 66,2-015, 65(216)-418, 16-212, and 23015 airfoil sections. Schileren photographs of the air flow and data on the wake characteristics was also obtained.

Report presenting an investigation of aileron flutter associated with high-speed flight. When the aileron control system was modified by installing a hydraulic irreversible unit, it was possible to delay aileron flutter and reduce its amplitude. Results regarding the aileron flutter with and without the modifications, analysis of the time histories for the control systems, and relation between aileron upfloat and flutter are provided.

Report presenting the air-flow behavior over the wing of an XP-51 airplane including photographs of tufts attached to the wing surface and chordwise pressure distributions. A comparison of tuft studies from flight results are compared with results from wind-tunnel testing. Three types of flow were observed: steady flow, unsteady flow, and break-away flow are provided.

Further data on the changes in length and weight of expanded graphite samples which were exposed in the pile in atmospheres of oxygen, carbon dioxide, and helium show that all three gases produce roughly the same shrinkage and weigh loss. This result is unexpected in that there is no precedent for such behavior in a helium atmosphere; however, it was found that water vapor had entered the helium stream by some unknown means and had condensed on the plugs at the inlet end of the tube. This opens the possibility that the graphite in the helium-filled tube was attacked by the reaction C + H{sub 2}O = CO + H{sub 2}. This experiment is to be repeated. The data are tabulated in this report. The expansion of the graphite before the experimental exposure was in all cases very nearly 0.6% per 1000 MD/CT. Both the D and the F Piles were scrammed by a power surge on April 14. Eight of the vertical rods did not drop into the D Pile. These and subsequent rod difficulties delayed the start up to such an extent that the reactivity losses associated with the build up of xenon poison and the cooling of …

"Results of tests of an airspeed head mounted on a freely falling body are presented in preliminary form. Measurements were made throughout the transonic speed range. Details and dimensions of the airspeed head and the body are given in figure 1" (p. 1).

Partial measurements in flight of the handling qualities of a Grumman XF7F-1 airplane were investigated. Results are for low altitude and normal center of gravity conditions only.

Memorandum presenting a calculation of the trajectories for a supersonic antiaircraft missile by a step-by-step integration method for a number of different conditions. The effects of changing drag, initial thrust ratio, and weight ratio, which are the principal variables controlling the trajectory for a fixed launching angle, were investigated.

Report presenting a method for calculating the drag, in a real compressible fluid and at subcritical Mach numbers, of airfoil sections at arbitrary life coefficients and of bodies of revolution at zero angle of attack. The values of drag coefficient are compared with values obtained for the same configurations by other methods. The differences between the results are found to lie withint he limits of accuracy of current experimental techniques.

Report presenting measurements of the behavior at supercritical Mach numbers of ailerons on a jet-propelled fighter plane. Results regarding aileron upfloat and aileron oscillations are provided.

"An investigation of an NACA submerged intake installation on the Ryan FR-1 was conducted to determine the full-scale aerodynamic characteristics of this installation. In addition, tests were conducted on the submerged inlet with revised entrance lips and deflectors to determine the configuration which would result in the best dynamic pressure recovery measured at the inlet for this installation without a major rework of the entrance. Stalling of the air flow over the inner lip surface created excessive dynamic pressure losses with the original entrance. The revised entrance produced a 12-percent increase in dynamic pressure recovery at the design high-speed inlet-velocity ratio and resulted in an improvement of the critical-speed characteristics of the entrance lip" (p. 1).

Tests of a PB2Y-3 flying boat were made at the U.S. Naval Air Station, Patuxent River, Md., to determine its hydrodynamic trim limits of stability. Corresponding tests were also made of a 1/8-size powered dynamic model of the same flying boat in Langley tank no. 1. During the tank tests, the full-size testing procedure was reproduced as closely as possible in order to obtain data for a direct correlation of the results. As a nominal gross load of 66,000 pounds, the lower trim limits of the full-size and model were in good agreement above a speed of 80 feet per second. As the speed decreased below 80 feet per second, the difference between the model trim limits and full-scale trim limits gradually became larger. The upper trim limit of the model with flaps deflected 0 deg was higher than that of the full-size, but the difference was small over the speed range compared. At flap deflections greater than 0 deg, it was not possible to trim either the model of the airplane to the upper limit with the center of gravity at 28 percent of the mean aerodynamic chord. The decrease in the lower trim limits with increase in flap …

Report presenting tests to determine the effect of sweepback angle and aspect ratio on the drag at supersonic speeds of wings of NACA 65-009 airfoil section. The current report is part of a bigger investigation and includes results for aspect ratios of 3.8 and 5.0. Results regarding the drag coefficient and general effect of aspect ratio are provided.

Abstract: The output signal of a linear accelerator may have a rise time of 1-2 x 10[minus]7 seconds. Therefore, the output of a pulse height selector operating on this signal has a variation of delay from the original signal of about this amount. In the instrument to be described in this technical report this difficulty is largely resolved.

Report presenting measurements downwash angles behind a model of a high-aspect-ratio wing at points near the probable tail location at Mach numbers up to 0.89 in the high-speed tunnel. The model has an NACA 65-210 section, an aspect ratio of 9.0, a taper ratio of 2.5:1, no twist, dihedral, or sweepback. Results regarding experimental data and comparison of experimental and calculated results are provided.

A theoretical analysis of the temperature distribution through the trailing portion of a blade near the coolant passages of liquid cooled gas turbines was made. The analysis was applied to obtain the hot spot temperatures at the trailing edge and influence of design variables. The effective gas temperature was varied from 2000 degrees to 5000 degrees F in each investigation.