Preliminary results at high speeds indicate lower bearing temperatures, less internal bearing wear, and greater reliability of the conventional, cage-type cylindrical roller bearings than of either full-complement or special cageless roller bearings of the types investigated, although the latter bearing types have been operated successfully to DN values of 1.0 X 10 superscript 6.

Report presenting load measurements using the swept-wing Bell X-5 and Douglas D-558-II research airplanes during flights in which reductions of longitudinal stability were experienced when pilots attempted to perform routine test maneuvers at moderate values of lift. Results regarding the maximum angles of attack and sideslip measured, pitching accelerations, horizontal-tail loads, wing loads, and stability deficiencies are provided.

Memorandum compiling summaries from NACA reports on fuel that were published between July 1945 and 1952. The summaries are intended to be detailed enough to eliminate the need to obtain the complete report.

Report presenting an investigation in the full-scale tunnel to determine the effects of a Fowler type slotted flap on the aerodynamic characteristics of a semispan 49.1 degree sweptback wing with NACA 65A006 airfoil sections streamwise, an aspect ratio of 3.78, and a taper ratio of 0.59. Results regarding the pitching-moment curve, effect of flap deflection, and lift increments are provided.

"During the course of an investigation by the Langley Pilotless Aircraft Research Division regarding the effectiveness of spoilers and ailerons on sweptback tapered wings, it was necessary to test a given control configuration on wings of varying degrees of stiffness. In the process of conducting these tests, repeated wing failure was experienced with the weaker wing-spoiler configurations, whereas no failure occurred with any of the wing-aileron models. An investigation which was conducted by means of rocket-propelled test vehicles in free flight showed that the cause of the repeated failures was flutter of the bending-torsion type" (p. 1).

Report presenting a transonic investigation made by the free-fall technique of a plane wing and a cambered and twisted wing, each with an aspect ratio 6, taper ratio of 0.5, and a sweepback of 45 degrees. Measurements were made of the loads on the exposed wings, pressures on the fuselage in the vicinity of the wing, and acceleration and angle of attack of the complete model.

"The over-all performance of a 16-stage axial-flow compressor was determined with various stator-blade resettings and a reduction in solidity of the rotor blades in the last three stages. It was shown that little control over the sudden change in slope of the surge-limit line at intermediate speeds was obtained with the blade modifications attempted, except that some change in speed at which the change in slope occurred could be effected by stator-blade resettings" (p. 1).

An analysis is made of the factors affecting the weight-flow rate per unit frontal area of centrifugal compressors with axial-flow vaned diffusers preceded by mixed-flow vaneless sections. It is shown that, for specified inlet conditions to the impeller and vaned diffuser, the weight-flow rate is increased at the expense of pressure ratio and vice versa. Charts are presented to help the designer make a satisfactory compromise between weight-flow rate and pressure ratio. Some conclusions of the investigation are : (1) Prewhirl is of negligible value in centrifugal compressors designed for high weight-flow rates.

Report presenting an experimental investigation performed to determine the effect on base and forebody pressures of using a sting modified with varying length splitter plates and fins instead of a conventional sting to support a cone-cylinder body of revolution.

Report presenting an investigation to evaluate the effects of nacelles and extended split flaps on the longitudinal characteristics of a wing-fuselage-tail combination of a type believed to be suitable for long-range high-speed airplanes. Wind tunnel tests to study the effects of the nacelles and flaps were conducted at a range of Mach and Reynolds numbers. Results regarding the effects of the nacelles with the tail off, effects of tail height, effects of nacelles with the tail on, and effects of flaps are provided.

From Introduction: "The airfoil sections tested, which differ only in thickness ratio, were the NACA 64-006, 64-008, 64-010, and 641-012. Lift, drag, and pitching-moment data were obtained for Mach numbers of 0.3 to that for tunnel choke at angles of attack of -2^o to 31^o. The results of this investigation are reported herein."

Report presenting an investigation of the performance of slurry fuels consisting of 50 percent magnesium powder in a hydrocarbon carrier in a flight-type, 6.5-inch-diameter ramjet engine mounted in a connected-pipe facility. Results regarding the slurry performance and a comparison of slurry and ethylene performance are provided.

Report presenting an investigation to determine the effects of center-of-gravity position on the gust loads of a delta-wing model with the leading edge swept back 60 degrees. A 15-percent change in the center-of-gravity position on the mean geometric chord produced a 7.5-percent change in load for the model in a sharp-edge gust and a 35-percent change in load in a gust with a 6.5 chord gradient distance.

Report presenting a cascade-general-momentum theory method for calculating the operating conditions of a supersonic propeller annulus throughout the flight Mach number range. General flow patterns about the cascade and adjustments to free-stream conditions are discussed.