Report presenting outdoor static testing made on two high-solidity propellers of different design, one shrouded and the other unshrouded. Three shrouds were tested to determine the effects of shroud length and exit area. Results regarding the action of shroud, results and comparison of propellers, and comparison with theory are provided.

Report presenting an investigation to correlate the engine service performance of cast Vitallium turbine buckets with standard laboratory metallurgical data. Data was obtained on four turbine wheels of Timken alloy with cast Vitallium buckets. Results regarding the engine test and metallurgical examination are provided.

Report presenting an investigation of an NACA 65A006 airfoil equipped with high-lift devices, including a 0.15-chord drooped-nose flap and a 0.20-chord plain trailing-edge flap. Airfoil section lift, pitching-moment, and drag characteristics obtained at high Reynolds numbers and low Mach numbers with the flaps deflected individually and simultaneously are presented. At Reynolds numbers up to 9.0 x 10(exp 6), the optimum combination of drooped-nose and plain trailing-edge flaps increased the maximum section lift coefficients from 0.78 to 1.89.

Report presenting high-speed wind tunnel testing of horn- and overhang-balance elevators on a full-scale, semispan, horizontal tail. The effects of unshielding the horn and unsealing the overhang were investigated. Results regarding aerodynamic characteristics, distortions of the tail, and critical Mach numbers are provided.

Report presenting calculated performance characteristics of a ducted rocket with gasoline and liquid oxygen as the fuel mixture and with a mass flow of 1 slug per second. Evaluations of net thrust, frontal area, thrust per unit frontal area, and specific fuel consumption are given for all of the flight conditions under which it might operate.

Memorandum presenting a wind-tunnel investigation conducted to determine the rotary stability characteristics in yawing flow of a series of untapered wings with angles of sweep of -45, 0, 45, and 60 degrees. The results of the yawing-flow tests indicated that the values of the rotary derivatives agreed fairly well with simple sweep theory for a moderate range of lift coefficients.

From Introduction: "An analysis of an engine having a division of work such that the power of the reciprocating engine is just sufficient to drive the compressor is reported herein. This combination of a reciprocating-type internal-combustion engine that drives its own supercharging compressor and generates gas for further expansion through a turbine will be called a piston-type gas generator in this report."

Report presenting an investigation of a turbojet engine with compressor-inlet total pressure at various values below that of the exhaust pressure to determine engine performance under conditions simulating operation with inlet-duct losses. Results regarding general performance, application to inlet-duct losses, application to airplane boundary-layer control, and application to turbojet-engine thrust control are provided.

Memorandum presenting wind-tunnel tests at high subsonic Mach numbers conducted on a model of a pursuit airplane with a 45 degree sweptback wing. Tests were made to determine the effect of the wing trailing-edge angle, the fuselage contour at the wing-fuselage intersection, and an extension at the leading edge of the wing root.

Report discussing flight tests of airplane-like models to determine the effect of airfoil section profile and thickness ratio on the zero-lift drag of low-aspect-ratio wings at supersonic speeds. Five rectangular wings with the same aspect ratio and a variety of airfoil thicknesses were tested to determine the effect of thickness ratio.

Report presenting a wind tunnel investigation to determine the downwash angles, dynamic pressure loss, and wake width behind wings with sweep angles of 45, 30, and 0 degrees. Results indicated that the spanwise distribution of downwash was affected by sweep in a manner similar to span loading, increased toward the root by sweepforward and toward the tip by sweepback.

Report presenting flight tests to determine the longitudinal stability and control characteristics of models of the Lark pilotless aircraft. Testing included the standard configuration with the horizontal wing flaps deflected 0 degrees, 15 degrees, and 60 degrees, and a test with the tail surfaces in line with the wings with the wing flaps not deflected. Results regarding time-history records, drag, longitudinal stability, and control effectiveness are provided.

The gust and draft velocities from records of NACA instruments installed in P-61C airplanes participating in thunderstorm flights at Clinton County Army Air Field, Ohio, from August 13, 1947 to August 15, 1947 are presented.

"Investigations were made of the turbine from a Mark 25 torpedo to determine the performance of the unit with three different turbine nozzles at various axial nozzle-wheel clearances. Turbine efficiency with a reamed nondivergent nozzle that uses the axial clearance space for gas expansion was little affected by increasing the axial running clearance from 0.030 to 0.150 inch. Turbine efficiency with cast nozzles that expanded the gas inside the nozzle passage was found to be sensitive to increased axial nozzle-wheel clearance" (p. 1).

"Tests of a 1/20-scale dynamically similar model of the Northrop B-35 airplane were made to study its ditching characteristics. The model was ditched in calm water at the Langley tank no. 2 monorail. Various landing attitudes, speeds,and conditions of damage were simulated during the investigation. The ditching characteristics were determined by visual observation and from motion-picture records and time-history acceleration records" (p. 1).

"An investigation of the spin and recovery characteristics of a scale model of the Grumman XF9F-2 airplane has been conducted in the Langley 20-foot free-spinning tunnel. The effects of control settings and movements on the erect and inverted spin and recovery characteristics of the model in the flight loading were determined. The investigation also included spin-recovery-parachute, pilot-escape, and rudder-pedal- . force tests" (p. 1).

The gust and draft velocities from records of NACA instruments installed in P-61C airplanes participating in thunderstorm flights at Clinton County Army Air FIeld, Ohio, from August 7, 1947 to August 13, 1947 are presented.

This report contains the results of the investigation of the aerodynamic characteristics of the flying mock-up of the Consolidated Vultee XP-92 airplane as conducted in the Ames 40- by 80-foot wind tunnel, Data are presented for test conditions which would give information as to the limits of stability and controllability, and also, the effect of Reynolds number. No analysis of the data has been made.

"Flight tests have been made to determine the longitudinal stability and control and stalling characteristics of the P-47.E-30 airplane. The teat results show the airplane to be unstable stick free in any power-on condition even at the most forward center-of-gravity position tested. At the rearward center-of-gravity position tested the airplane also had neutral to negative stick-fixed stability with power on. The characteristics in accelerated flight were acceptable at the forward center-of-gravity position at low and high altitudes except at high speed where the control-force variations with acceleration were high" (p. 1).

Contains the results of an investigation in the Langley free-flight tunnel to determine the stability and control characteristics of a 1/12-scale dynamic free-flying model of the Consolidated Vultee 7002 airplane (a flying mock-up of the XP-92 airplane). The wing and vertical tail of this model were of triangular plan form with 60 degree sweepback of the leading edge. The results of both force and flight tests of the model are presented.

Memorandum presenting the results of measurements of gust and draft velocities within thunderstorms at an air field over a 7-day period. The data are summarized in tables and compared to previous flights.