Memorandum presenting an analysis of probable heat-exchanger weights for stationary and rotary regenerator heat exchangers for use in a hydrogen-expansion turbine engine. This is because rotary regenerators offer possibilities for a considerably lighter heat-exchanger core, possibly one-fourth that of the stationary regenerators.

Memorandum presenting a theoretical mixed-jet one-spool turbofan engine analyzed over a range of flight Mach numbers up to 2.95. The engine was characterized by an eight-stage fan-compressor unit. Results regarding performance maps, rotating stall, turbofan inlet axial velocity, and weight-flow variations are provided.

Performance characteristics of underslung vertical wedge inlet with porous suction at Mach numbers of 0.63 and 1.5 to 2.0.

Memorandum presenting an experimental and analytical study made at transonic speeds up to Mach number 1.43 to determine the ability of present calculation procedures to predict transonic drag-rise changes which result from physical model changes. Both wing-body and wing-body-tail configurations were investigated.

Memorandum presenting certain considerations and techniques pertinent to the application of the supersonic area rule to the design of airplane fuselages. Some of the factors considered are an extension of the rule to account for the interference effects of the wing and tail on the general flow field for asymmetrical configurations, the determination of fuselage area developments which result in approximately the minimum wave drag, and the influence of wing parameters and design Mach number on the effectiveness of fuselage shaping.

"Theoretical values of performance parameters for liquid ammonia and liquid fluorine as a rocket propellant were calculated on the assumption of equilibrium composition during the expansion process for a wide range of fuel-oxidant and expansion ratios. The parameters included were specific impulse, combustion-chamber temperature, nozzle-exit temperature, equilibrium composition, mean molecular weight, characteristic velocity, coefficient of thrust, ratio of nozzle-exit area to throat area, specific heat at constant pressure, coefficient of viscosity, and coefficient of thermal conductivity" (p. 1).

"Theoretical values of performance parameters for liquid ammonia and liquid fluorine as a rocket propellant were calculated on the assumption of equilibrium composition during the expansion process for a wide range of fuel-oxidant and expansion ratios. The parameters included were specific impulse, combustion-chamber temperature, nozzle-exit temperature, equilibrium composition, mean molecular weight, characteristic velocity, coefficient of thrust, ratio of nozzle-exit area to throat area, specific heat at constant pressure, coefficient of viscosity, and coefficient of thermal conductivity" (p. 1).

Memorandum presenting an instrument for recording and indicating the frequency and intensity of aircraft icing conditions to obtain statistical icing data over worldwide air routes during routine airline operations. Data of this type is needed to provide pertinent meteorological information necessary for the optimum design of ice-protection systems. The features that make this particular instrument desirable include the simplicity of operation, freedom from maintenance and operating problems, automatic operation upon encountering an icing condition, visual indications of icing intensity available to the pilot, total weight of 18 pounds, and continuous recorded data.

Different aircraft engines are categorized as being of interest to only the Army or Navy or to both armed services. A listing of the different engines is presented along with some statistics, namely, horsepower.

Report presenting an investigation of several wingless missile configurations for a range of Mach numbers to determine their lift, drag, and pitching-moment coefficients. Results for missiles having nose controls and missiles having tail controls are provided. The results were also compared to a conventional missile with wings.

Report presenting development tests on a model of the Republic F-105 airplane at a Mach number of 0.20. The purpose of the current investigation is to obtain the longitudinal force and moment characteristics of the model equipped with trailing-edge flaps of various spans and deflections. Results regarding the longitudinal stability characteristics and effect of the horizontal tail are provided.

Report presenting a flight investigation of a rocket-launched solid-fuel ram-jet engine designed to bypass cooling air around the fuel charge. The internally cooled combustor averted combustor burn-out during the flight test. Results regarding the net thrust coefficient, gross thrust coefficient, time history of the air specific impulse, and total fuel load are provided.

A compilation of the six technical papers presented at the NACA Conference on Engine Stall and Surge on February 3, 1955 at the Lewis Flight Propulsion Laboratory. A list of conference attendees is also provided.

Memorandum presenting an investigation of a can-type flame holder employing a fuel-air-mixture control sleeve in a 20-inch-diameter ramjet combustor conducted by free-jet and direct-connect techniques at a simulated flight Mach number of 3.0 and altitudes from about 70,000 to 80,000 feet. Results regarding the effect of shortening combustion chamber and effect of pilot-burner variables are provided.

Memorandum presenting an investigation of the effect of the number and width of annular flame-holder gutters on afterburner performance in a 26-inch-diameter afterburner test rig. The burner inlet temperature was held at 1250 degrees Fahrenheit. Results regarding the effect of gutter width on stability limits and effect of flame-holder blockage on pressure drop are provided.

Report presenting an investigation of the effects of afterburner-inlet total temperature, total pressure, velocity, fuel-air ratio, and afterburner combustion-chamber length on afterburner performance and stability limits using a cylindrical afterburner installed in a duct test rig. The afterburner was investigated over a range of total temperature, total pressure, velocity, and afterburner fuel-air ratios.

Memorandum presenting a preliminary investigation to determine the effects of alpha-particle bombardment on the creep rate of aluminum wire at 400 degrees Fahrenheit. The alpha radiation from an 85-millicurie polonium source appeared to decrease slightly the creep rate of the aluminum.

Report presenting an investigation of a surge inhibitor that was able to cause a considerable gain in stable-airflow operating range over the range of equivalent impeller tip speeds tested. While the inhibitor was designed to triple the stable-airflow operating range, it increased it more than eight times its original value.

Memorandum presenting a determination of the performance of a single-cylinder spark-ignition engine modified to operate on a compression-ignition cycle with a compression ratio of 8.0. Experimental data were obtained at an inlet-manifold pressure of 100 inches of mercury absolute, fuel-air ratios of 0.040 and 0.025, and engine exhaust pressures of 30 to 100 inches of mercury absolute. Results regarding single-cylinder-engine experimental data and full-scale-engine calculations are provided.

Report presenting investigations to determine the antiknock effectiveness of various additive-water solutions used as internal coolants in conjunction with AN-F-28, Amendment-2, fuel in a modified CFR engine.

From Introduction: "Water injection at the compressor inlet has been successfully used to increase the thrust of turbojet engines. References 1 and 2 indicate that the sea-level static thrust of a centrifugal-flow-type turbojet engine may be increased about 25 percent by use of liquid injection. Reference 3 indicates that greater thrust augmentation is possible at a compressor pressure ratio of 11 than of 4."

Report presenting a wind-tunnel investigation to determine the effects of leading-edge radius and maximum thickness-chord ratio on the variation with Mach number of the aerodynamic characteristics of several thin symmetrical NACA 4-digit-series airfoil sections. The variations with Mach number of the lift, drag, and pitching moment for a 4-percent-chord-thick airfoil section are not significantly affected by a change of leading-edge radius from 0.18 to 0.53 percent of the chord. Results regarding the leading-edge radius effects and maximum thickness-chord ratio are provided.

Memorandum presenting an investigation conducted in the 4- by 4-foot supersonic tunnel to determine the longitudinal stability and control characteristics of a model of a supersonic airplane configuration at Mach number 1.40. The model had a 40 degree sweptback wing with 10-percent-thick circular-arc sections normal to the quarter-chord line. The results indicated a high degree of longitudinal stability that was fairly constant throughout the trim-lift-coefficient range.

Report presenting a preliminary investigation of cone-type diffusers designed for minimum spillage at the inlet during operation in the supersonic tunnel at Mach number 1.85. Pressure recoveries of a series of stationary cones with included angles from 20 degrees to 60 degrees were investigated. Results regarding the pressure recovery with stationary cones and pressure recovery of movable-cone configurations are provided.