"Flight icing-rate data obtained in a dense and abnormally deep supercooled stratiform cloud system indicated the existence of liquid-water contents generally exceeding values in amount and extent previously reported over the midwestern sections of the United States. Additional information obtained during descent through a part of the cloud system indicated liquid-water contents that significantly exceeded theoretical values, especially near the middle of the cloud layer. The growth of cloud droplets to sizes that resulted in sedimentation from the upper portions of the cloud is considered to be a possible cause of the high water contents near the center of the cloud layer" (p. 1).

Report presenting an investigation conducted to determine the overall performance of the J73 two-stage turbine with a standard rotor-blade configuration. The turbine operated with a maximum brake internal efficiency between 0.91 and 0.92 at an overall pressure ratio of about 3.4 and 120 percent equivalent design rotor speed. Results regarding the overall performance, variation of equivalent weight flow with overall pressure ratio, and effect of limiting blade loading are provided.

Report presenting flight measurements of aerodynamic tail loads made on the Douglas D-558-II from which the variation with Mach number of the wing-fuselage aerodynamic center, static-longitudinal-stability parameter, the tail load per g, and the zero-lift wing-fuselage pitching-moment coefficient determined up to Mach number 0.87.

From Summary: "Force characteristics determined from tank tests of a 1/5.78-scale model of a hydro-ski-wheel combination for the Grumman JRF-5 airplane are presented. The model was tested in both the submerged and planing conditions over a range of trim, speed, and load sufficiently large to represent the most probable full-size conditions."

Report presenting a wind-tunnel investigation to determine the effects of two wing-root leading-edge plan-form modifications, including a notched leading-edge fillet and a rounded leading-edge fillet, on the low-speed longitudinal stability characteristics of an airplane model with a 50.7 degree sweptback wing. Results regarding stability at zero lift, variation of stability with lift coefficient, and lift and drag characteristics are provided.

Report presenting an investigation at transonic speeds to determine the control characteristics of a linked flap and spoiler. The control consisted of a linked combination of a quarter-span inboard plug-type spoiler and a full-span flap. Results regarding the hinge-moment, pitching-moment, lift, and rolling-moment are provided.

Report presenting an investigation using the NACA wing-flow method at transonic speeds to determine the contributions of wing, tail, and fuselage to the aerodynamic characteristics of a semispan airplane model with a long slender fuselage and straight wing and tail of low aspect ratio with faired symmetrical double-wedge airfoil sections 4.6 percent of the chord in thickness. Results regarding the drag, pitching moment, downwash, and lift are provided.

Report presenting an investigation to determine the feasibility of utilizing a reduced-chord rotor blading on the two-stage turbine of the J73 turbojet engine in order to reduce the weight. The turbine was operated as a component over a range of speeds and overall pressure ratios at turbine-inlet conditions corresponding to 35 inches of mercury absolute and 700 degrees R. Results regarding the overall performance, performance map, and peak efficiency are provided.

Report presenting an evaluation of the stage performance of the J73 turbine on the basis of previous performance investigations of the first stages alone and of the two-stage turbines with standard and with reduced-chord rotor blading for a range of rotational speeds and pressure ratios. The results demonstrated that both of the two-stage turbines and first-stage turbines had comparable performance.

Report presenting an investigation in the 4- by 4-foot supersonic pressure tunnel to determine the static longitudinal stability and control characteristics of a model of a 45 degree swept-wing fighter airplane at three Mach numbers. The results indicate that the static margin, which was fairly constant through the lift range, decrease from 32 to 27 percent mean aerodynamic chord with increase in Mach number from 1.41 to 2.01.

Memorandum presenting a flight investigation of the Bell X-5 variable-sweep research airplane in the 45 degree wing sweptback configuration over a range of Mach numbers. Lift and drag values are presented and a comparison is made with data obtained with a wing sweepback of 59 degrees.

Report presenting vibratory stress measurements on a supersonic-type propeller for forward Mach number up to 0.95. Results regarding the bending stress and torsion stress are provided.

The J33-A-27 compressor was operated at an inlet pressure of 14 inches of mercury absolute and ambient inlet temperature over a range of equivalent impeller speeds from 6100 to 11,800 rpm. At the design equivalent speed of 11,800 rpm, the J33-A-27 compressor had a peak pressure ratio of 4.40 at an equivalent weight flow of 105.7 pounds per second and a peak adiabatic temperature-rise efficiency of 0.745. The maximum equivalent weight flow at design speed was 113.5 pounds per second.

"The multistage turbine from the J73 turbojet engine has previously been investigated with standard and with reduced-chord rotor blading in order to determine the individual performance characteristics of each configuration over a range of over-all pressure ratio and speed. Because both turbine configurations exhibited peak efficiencies of over 90 percent, and because both units had relatively wide efficient operating ranges, it was considered of interest to determine the performance of the first stage of the turbine as a separate component. Accordingly, the standard-bladed multistage turbine was modified by removing the second-stage rotor disk and stator and altering the flow passage so that the first stage of the unit could be operated independently" (p. 1).

Memorandum presenting system analyses and autopilot design procedure for a supersonic pilotless aircraft with twin jet engines. The autopilots investigated were a gyro-actuated control, a gyro-actuated control with a rate-sensing device, and an electronic-hydraulic autopilot. Results regarding the airframe and gyro-actuated control system; airframe, gyro-actuated control, and rate servo; airframe and electronic-hydraulic autopilot; and contribution of method of analysis to system design are provided.

An investigation has been conducted in the Cleveland altitude wind tunnel to determine the operational characteristics of the I-40 jet-propulsion engine over a range of pressure altitudes from 10,000 to 50,000 feet and ram-pressure ratios from 1.00 to 1.76. Engine operational data were obtained with the engine in the standard configuration and with various modifications of the fuel system, the electrical system, and the combustion chambers. The effects of altitude and airspeed on operating speed range, starting, windmilling, acceleration, speed regulation, cooling, and vibration of the standard and modified engines were determined, and damage to parts was noted.

Report presenting an investigation at low speed to determine some of the effects of wing fences on the lateral stability derivatives of a flat-plate 60 degree delta-wing model oscillating continuously in yaw. Results regarding the variation with angle of attack, effect of frequency, effect of amplitude, number of fences, and some effects of fence geometric characteristics are provided.

Report presenting experimental data from calm- and rough-water landing impacts with a dynamic model of a seaplane incorporating a flat-bottom hydro-ski mounted on a rigid strut and on a shock-absorber strut. Results regarding the fixed-ski case and translating-ski case are provided.

Report presenting an investigation at a free-stream Mach number of 1.80 in a blowdown tunnel to study the effect on the pressure distribution of a zero-angle-of-attack wing surface when certain exhaust parameters of a hot turbojet engine are varied. Results regarding shock wave and pressure coefficients are provided.