Report presenting a brief investigation conducted to determine the effects of a 60-40 air flow distribution to the twin inlet ducts of an axial-flow turbojet engine. Data were obtained over a range of exhaust gas temperatures at several altitudes at Mach number 0.64. Results regarding the effect on pressure and temperature patterns, compressor performance, effect on combustor and turbine performance, engine pumping characteristics, and operational characteristics are provided.

Report presenting a review of the literature pertaining to the use of orthotoluidine and triethylamine in rocket propellant combinations and a summary with particular emphasis on ignition delay investigations and fuel mixture applications. The survey indicated that orthotoluidine is about as good a rocket fuel as aniline with respect to cost, performance, and ignition characteristics, but it has a wider temperature application because of its lower freezing point.

Report presenting an investigation to determine the predictability of using ceramals with comparatively low strategic material content for the blades of aircraft turbines, including testing with four different blade root configurations. The most favorable results were obtained for ceramal turbine blades with single serration interlock and dovetail root configurations. Results are also provided for fir-tree blade runs and 4-pin blade runs.

Report presenting an investigation of the effects of heat transfer on boundary-layer transition at higher Reynolds numbers, greater amounts of heating, and a more extensive study of the effects of surface irregularities than what was published in a previous report. Report presenting tests with a smooth model and tests with surface roughness and tunnel flow disturbance are provided.

Report presenting a flight investigation to determine the drag and stability at low lift coefficients of models of a modified-delta-wing airplane at a range of Mach and Reynolds numbers. A summary of the drag and stability data from the tests is provided.

From Introduction: "In response to the ever-increasing need for high thrust augmentation, an investigation was conducted that had as its primary objective the attainment of maximum exhaust-gas temperature and thrust (ref. 1). The investigation reported herein was therefore conducted to ascertain the operational limits of the most promising high-temperature afterburner design of reference 1 and to determine its performance over a wind range of flight conditions."

Report presenting a study of the effects of high reactor and cycle temperatures and the effect of thickness of high-temperature fuel element materials on the feasibility of the nuclear-powered direct-air-cycle aircraft for flight at Mach number 1.5 and an altitude of 35,000 feet. Testing occurred over a range of reactor fuel temperatures, turbine-inlet temperatures, and reactor fuel plate thicknesses.

Report presenting an investigation studying the effects of compressibility on the internal-flow characteristics of an NACA 1-series cowling-spinner combination equipped with a dual-rotation propeller at Mach numbers up to 0.8. Two propellers were examined, one with a sealed propeller-spinner juncture and one with a raised-platform-airfoil shaped juncture. The propeller was not found to have appreciable compressibility effects on the impact pressures when operating at design cruise blade angle.

Report presenting an investigation to determine the effect of rate of flap deflection on flap hinge moment and wing lift at a range of Mach and Reynolds numbers. For the rate of flap-deflection range investigated, the hinge-moment coefficient was practically independent of rate of flap deflection.

From Summary: "An experimental investigation of high-frequency combustion oscillations (screaming) was conducted with a 100-pound-thrust acid-hydrocarbon rocket engine and a 500-pound-thrust oxygen-fuel rocket engine. The oscillation frequencies could be correlated as a linear function of the parameter C/L, where C is the experimentally measured characteristic velocity and L is the combustion-chamber length. The tendency of the engines to scream increased as chamber length was increased. With engine configurations that normally had a low efficiency, screaming resulted in increased performance; at the same time, a five to tenfold increase in heat-transfer rate occurred. It was possible, however, to achieve good performance without screaming."

Report discussing the importance of designing aircraft turbines so that the entire range of operating conditions has been considered. In this particular investigation, the compressor performance was used to determine the turbine design requirements for a turbine-propeller engine to be operated up to altitudes of 40,000 feet and flight velocities up to 600 miles per hour. The two modes of engine operation considered were constant exhaust-nozzle area and variable exhaust-nozzle area.

From Introduction: "Because of variation in the static-pressure drop across the porous material and in the cooling air required along the length of afterburner combustion chambers, a prescribed distribution of permeability is usually necessary. However, as a preliminary investigation, this report is concerned only with the attainment of uniform permeability. The results of an experimental investigation, conducted at the NACA Lewis laboratory, to determine the permeabilities of five thick meshes of wire filter cloth are presented herein."

An analytical investigation was made of two supersonic interceptor type airplanes to determine the most desirable turbojet engine characteristics for this application The airplanes were designed differently primarily because of the amount of subsonic flight incorporated in the flight plan--one flight having none and the other, a cruise radius of 400 nautical miles. Several power plant design variables were varied independently to determine the effect of changes in each parameter on airplane performance. These parameters included compressor pressure ratio, compressor efficiency, turbine-inlet temperature, afterburner temperature, engine specific weight, and air-handling capacity. The effects of using a convergent-divergent exhaust nozzle and of changing the design flight Mach number were also investigated.

Report presenting testing of four delta-wing and body combinations at specified Mach numbers to determine the effect of oscillation amplitude on the damping in pitch. The body tested was the same, but the wings had 25 degree, 30 degree, 35 degree, and 45 degree semiapex angles. Results indicate that the damping-in-pitch parameter can be predicted by theory, and when a variation of this parameter with amplitude occurs, it is usually small and camping increases with decreasing amplitude.