Report presenting a single, ordinary, nonlinear differential equation of second order that can be used for determining entry into an exponential planetary atmosphere. The reduced equation includes various terms, some of which represent the gravity force, the centrifugal acceleration, and the lift force. A number of solutions for lifting and nonlifting vehicles entering at various initial angles are obtained from the complete nonlinear equation.

"The amount of water in cloud droplet form ingested by a full-scale supersonic nose inlet with conical centerbody was measured in the NACA Lewis icing tunnel. Local and total water impingement rates on the cowl and centerbody surfaces were also obtained. All measurements were made with a dye-tracer technique" (p. 1).

Report presenting an experimental investigation to determine the effects of planing in a wake on the forces of a planing surface and to locate desirable positions in the wake with regard to the lift and lift-drag ratio of the planing surface. Two combinations of hydro-skis were tested: one with two in tandem and one with three arranged with one hydro-ski in the front and two in the back. Results indicated that the rear hydro-ski in tandem arrangement could have large increases in lift coefficient and small improvements in lift-drag ratio compared with the regular configuration.

Note presenting flight tests conducted with a medium-size single-rotor helicopter, one blade of which was equipped with strain gages, to determine the effects of retreating-blade stall on the rotor blade bending and torsional moments during high-speed flight and pull-up maneuvers. The results indicate that retreating-blade stall has a substantial effect on the periodic rotor blade moments. Results regarding the effect of stall in steady forward flight and effect of stall in pull-up maneuvers are provided.

Report presenting the use of the slender-wing-type analysis to obtain general expressions for the surface pressure, lift, and rolling moment for cambered wings with swept trailing edges. The results are specialized to give the additional loading due to the deflection of trailing-edge control surfaces and the loading due to a particular type of wing twist. A numerical example for aileron control is included.

Note presenting experiments conducted to determine the effect of a strong axial magnetic field on the flow of mercury through a circular channel. The magnetic induction was 15,000 gauss, and the channel was a pyrex tube 17-1/4 inches long and 0.027 inch inside diameter. The results indicated that the stabilizing effect occurred only at Reynolds number above 5,000, so that the region of practical applicability seems to be at fairly high Reynolds numbers and when there are only slight disturbances in the flow.

Report presenting a comparison of several methods for handling excess inlet flow for the Mach number range from 1.5 to 4.0. The following techniques were examined and evaluated: normal- and oblique-shock spillage, bypassing through an auxiliary exit, bypassing to an ejector exhaust nozzle, and bypassing the excess flow through an auxiliary ramjet engine. Charts are presented for the thrust penalties at a variety of Mach numbers.

Ram-jet cycles that use the chemical energy of dissociated oxygen for propulsion in the ionosphere are presented. After a review of the properties and compositions of the upper atmosphere, the external drag, recombination kinetics, and aerodynamic-heating problems of an orbiting ram jet are analyzed. The study indicates that the recombination ram jet might be useful for sustaining a satellite at an altitude of about 60 miles. Atmospheric composition and recombination-rate coefficients were too uncertain for more definite conclusions. The ram jet is a marginal device even in the optimistic view.

Report presenting some measurements of the aerodynamic forces and moments on a rectangular wing of aspect ratio 2 which oscillated about the midchord. The measurements were made at four frequencies over a range of Mach and Reynolds numbers. Results regarding the calculated values of various theories and coefficients of lift and moment are provided.

Report presenting the results of tests conducted on a large bomber-type airplane to determine the ground-reaction forces imposed on the main landing gear under actual landing conditions. The vertical force on the landing gear truck at which the oleopneumatic shock strut began to compress varied over a wide range. Results regarding vertical forces, drag forces, and side forces are provided.

Report presenting heat-transfer measurements made in turbulent flow at a variety of Mach and Reynolds numbers through the use of an axially symmetric annular nozzle consisting of an inner shaped center body and an outer cylindrical sleeve. The results are presented as Stanton number and recovery factor as a function of Reynolds number. Stanton number was found to decrease with an increase in Reynolds number and usually decreases with an increase in Mach number.

Memorandum presenting an experimental investigation to determine the effect on drag of applying the moment-of-area-rule modifications to wing-body combinations with various wing plan forms. The effect of mounting air-to-air type missiles on the wing-mounted bodies of revolution which are part of the moment-of-area-rule modification was also investigated.

Transonic flutter derivatives for unswept wing control surface configurations determined by pressure cell measurements. The control surfaces were mounted on a wing with an aspect ratio of 3, a taper ratio of 0.6, and a wing-thickness ratio of 0.06. Results regarding aerodynamic balance, vortex generators, splitter-plate configurations, and wedges are provided.

Report presenting a determination of transonic flutter characteristics from pressure cell measurements on control surfaces sinusoidally oscillated at an amplitude of plus or minus 1.08 degrees at frequencies from 5 to 30 cycles per second. Various control-surface configurations were investigated, including internal and external aerodynamic balance, vortex generators, a splitter-plate type of control surface, and superposition of triangular shaped wedges or tetrahedra along the rear portion of the control-surface chord.

Report presenting an investigation in an altitude test chamber using a turbojet engine equipped with an afterburner and ejector to compare directly two techniques of determining thrust that are both applicable to flight installations. One method uses a swinging uncooled rake at the ejector outlet while the other requires extensive instrumentation to measure the momentum forces of systems and the force on the internal surface of the ejector nozzle. Results regarding the swinging-rake technique and internal-pressure technique are provided.

Memorandum presenting results of a supersonic flutter investigation of three low-aspect-ratio control surfaces. Two controls were all-movable but the third had a fixed cutout. Results regarding the experiments and calculations are provided.

Report presenting the results of a supersonic flutter investigation of three low-aspect-ratio control surfaces, two which had all-movable controls and one with a fixed cutout. Experimental results are provided and compared to calculations using the piston theory for plan form 2. Modifications for improving the flutter of the various control surfaces are also described.

"A wind-tunnel investigation was made to determine the effects on the aerodynamic characteristics of a 35 degree swept-wing airplane of applying area-suction boundary-layer control to the trailing-edge flaps. Flight tests of a similar airplane were then conducted to determine the effect of boundary-layer control in the handling qualities and operation of the airplane, particularly during landing. The wind-tunnel and flight tests indicated that area suction applied to the trailing-edge flaps produced significant increases in flap lift increment" (p. 1).

Memorandum presenting lift and drag characteristics that have been determined in flight in the landing-approach configuration on 41 jet-propelled fighter-type airplane arrangements, including various wing boundary-layer-control installations. Minimum comfortable approach speeds for carrier-type landings were evaluated for these airplanes by four test pilots. Results regarding the presentation of data, methods for the prediction of minimum comfortable approach speed, reasons for limiting approach speed, comparison of flight and predicted approach speeds, and comparison of test pilots' and service pilots' approach speed are provided.

Report presenting lift and drag characteristics in the landing-approach configuration on 41 jet-propelled fighter-type airplane arrangements using flight testing. Minimum comfortable approach speeds were evaluated by four test pilots. Suggestions for achieving optimal speeds for approach under various conditions are also provided.

Report presenting testing of two blunt-nose models, a flat-face-cone and a hemisphere-cone, at Mach numbers up to 4.7. The main purpose was to determine information about heating rates and transition for different blunt nose shapes for long-range ballistic missiles. Information about pressure measurements and heat transfer is provided.

Memorandum presenting results of tests for possible flutter of a dynamically and elastically scaled model of a proposed all-movable horizontal tail surface for the North American X-15 airplane. Tests at Mach number 6.86 were made on the scaled model and on several other configurations with lower stiffnesses.

"Results of tests for possible flutter of a dynamically and elastically scaled model of a proposed all-movable horizontal tail surface for the North American X-15 airplane are presented herein. Tests at a Mach number of 6.86 were made on the scaled model and on several other configurations having lower stiffness. Flexibility influence coefficients and calculated modes and frequencies for the weakest configuration are presented" (p. 1).

Memorandum presenting an investigation to determine the performance of the XJ79-GE-1 turbojet engine and its components, while operating as integral parts of the engine, conducted in an altitude test chamber. Data were obtained over a range of Reynolds number indices and for various settings of the variable compressor stators and variable-area exhaust nozzle from fully open to fully closed positions. Results regarding the component performance and engine performance are provided.