A lightweight instrument that utilizes resistance-wire electric strain gases to measure propeller-shaft thrust has been developed. A wind-tunnel investigation on a propeller installed, on a single-engine pursuit airplane showed that the instrument gave a reliable indication of propeller-shaft thrust to an accuracy of +/-2 percent within its calibrated range. No attempt was made to determine the relation of indicated shaft thrust to net propeller thrust.

Report presenting a partial-span wing tested to determine the cause of a flutter which had occurred in high-speed flight. Changes were made to the wing stiffness, location of the center of gravity of the wing, and the mass balance of the aileron. Results regarding the effect of wing changes on flutter, effect of aileron changes on flutter, shock-wave study, and static aerodynamic coefficients are provided.

Memorandum describing preliminary investigations of two 3-inch-diameter slotted test sections over a range of pressure ratios from 1.3 to 10.0. The two test sections varied based on the number of slots and amount of open space, but they showed no appreciable difference in performance. Results regarding the slots with no chamber around the test section and with a closed chamber around the test section are provided.

Report presenting the lift and pitching-moment characteristics of two wings of the same plan form measured over a range of Mach and Reynolds numbers using the wing-flow method. One wing had a symmetrical airfoil section and no twist, while the other was cambered and twisted to support a uniform load distribution at a lift coefficient of 0.25 at Mach number 1.5. A comparison with previous testing is also provided.

Report discussing an investigation of the aerodynamic characteristics of an airfoil-forebody swept flying boat hull with a wing and tail swept back 51.3 degrees at the leading edge. The swept hull's minimum drag coefficient was about the same as the parent model or streamline model. Various combinations of flaps were also utilized.

Report presenting wind-tunnel tests that have been conducted to evaluate the independent effects of Reynolds and Mach numbers on the aerodynamic characteristics of a horizontal tail of aspect ratio 4.5 with a plain sealed elevator with a tab. Lift, drag, pitching moment, elevator hinge moment, tab hinge moment, streamwise distribution of static pressure at the midsemispan, and pressure difference across the elevator-nose seal were measured.

Report presenting an investigation of the low-speed, power-off static longitudinal stability and control characteristics of a canard model with a triangular wing and horizontal tail in the free-flight tunnel. Results regarding the horizontal tail used to overcome change in stability and horizontal tail used for longitudinal control are provided.

Report presenting turbulent-boundary-layer profiles at large Reynolds numbers and with Mach numbers up to 1.2. In this investigation, velocity profile shapes were substantially unaffected by compressibility. Results regarding the temperature considerations, velocity profiles, and turbulent boundary layer under normal shock are provided.

Report discussing an investigation to determine the effect of sweepback on the static and rolling stability derivatives of a series of wings with a taper ratio of 0.6 and an aspect ratio of 4. The influence on the straight-flow characteristics, rolling-flow characteristics, and aileron characteristics are provided.

Report presenting the specific impulse of liquid diborane and liquid oxygen over a range of mixture ratios in a 100-pound-thrust rocket engine operating at a combustion-chamber pressure of 300 pounds per square inch absolute. A faired curve through the experimental data had approximately the same shape as the theoretical curve.

NACA instrumentation has been installed in the Northrop X-4 airplane to obtain stability and control data during the Northrop conducted acceptance tests. The results o. the third flight of the X- ll. number 1 airplane are presented in this paper. The results of this flight showed that the directional stability as measured in steadily increasing sideslips was positive and high and that the lateral stability was positive.

Results of previous model ditching tests of the Lockheed Constellation airplane are reported. Further model tests have been made to determine the probable ditching characteristics and the proper ditching technique for the airplane with the Speedpak attached. This paper presents the results of these tests. Design information was furnished by the Lockheed Aircraft Corporation. A three-vies drawing of the airplane with the Speedpak attached is shown. The tests were made in calm water at the Langley tank no.2 monorail.

Report presenting a wind-tunnel investigation to determine the effect of propeller operation on the characteristics of submerged inlets. The tests were performed with a model of a hypothetical fighter airplane powered by a turbine-propeller unit. The propeller had eight blades with thin airfoil shanks and dual rotation and the submerged inlets were placed in the fuselage behind the propeller and forward of the wing.

A model of a Consolidated Vultee Aircraft Corporation Skate 7 sea-plane was tested in Langley tank no. 2. Resistance data, spray photographs, and underwater photographs are given in this report without discussion.

From Summary: "A single-stage modification of the turbine from a Mark 25 torpedo power plant was investigated to determine the performance with two nozzles and three rotor-blade designs. The performance was evaluated in terms of brake, rotor, and blade efficiencies at pressure ratios of 8, 15 (design), and 20. The blade efficiencies with the two nozzles are compared with those obtained with four other nozzles previously investigated with the same three rotor-blade designs."

A Japanese log rodmeter of the rotating-vane impeller type, with a commutator on the impeller shaft, was calibrated in Langley tank no. 1. The rotational speed of two impellers was determined for forward speeds up to 24 knots at angles of yaw up to ?10 0 . In general, the rotational speeds of two apparently identical impellers tested in the rodmeter decreased with increasing yaw angle, right yaw causing a greater decrease than left yaw. The difference in calibration between the two impellers was approximately the same as that produced by a change in yaw angle from 50 left to 50 right. Evidence of cavitation within the impeller fairing appeared at speeds above 24 knots.

A 0.1-size powered dynamic model of a large, high-speed flying boat was landed in Langley tank no. 1 into oncoming waves 4 feet high (full size). The model was tested with two afterbodies of differing lengths (4.12 and 6.63 beams). The short afterbody had a constant angle of dead rise of 22.5deg and a keel angle of 6.5deg. The long afterbody had warped dead rise and a keel angle of 8.5deg. The vertical accelerations were slightly greater and the maximum angular accelerations and maxim= trims were slightly less for the model with the long afterbody than for the model with -the short afterbody. A wave length of 210 feet (full size) imposed the highest accelerations on the model with either the long or the short afterbody.

"An investigation was conducted to determine the effect of turbine-disk cooling with air on the efficiency and the power output of the radial-flow turbine from the Turbo Engineering Corporation TT13-18 turbosupercharger. The turbine was operated at a constant range of ratios of turbine-inlet total pressure to turbine-outlet static pressure of 1,5 and 2.0, turbine-inlet total pressure of 30 inches mercury absolute, turbine-inlet total temperature of 12000 to 20000 R, and rotor speeds of 6000 to 22,000 rpm, Over the normal operating range of the turbine, varying the corrected cooling-air weight flow from approximately 0,30 to 0.75 pound per second produced no measurable effect on the corrected turbine shaft horsepower or the turbine shaft adiabatic efficiency" (p. 1).