A study of mixtures of pure methanol and trimethyl borate showed that the composition can be accurately obtained by a simple density determination. The refractive-index determination gives the composition with much less accuracy. The potentiometric titration of boric acid is also discussed.

Report presenting a technique and the results obtained of wind-tunnel forced-oscillation tests on a model of the Douglas D-558-II airplane which was instrumented to obtain the dynamic cross derivative and static derivative. Tests were conducted for a range of Mach numbers and angles of attack. Results regarding sample calculations of the period and damping of the full-scale airplane are provided despite not being conclusive due to the inadequate number of flight conditions investigated.

"A transonic turbine with a stator trailing-edge thickness reduced from 0.030 to 0.010 inch has been investigated experimentally. The performance results indicated an increase in efficiency of 0.6 of a point at design operation, and as much as 2.4 points at off-design conditions, as a result of reducing the trailing-edge thickness. This improvement could only be partially accounted for by the theoretical change in mixing loss for the two stator-blade rows, and it was felt that the improvement was largely due to a reduced amount of low-velocity fluids entering the rotor and the interference effect of these fluids with the mainstream flow" (p. 1).

Report presenting an investigation of the ditching characteristics of the Boeing 707 jet transport in tank no. 2. Various conditions of damage, landing attitude, and speed were investigated. Data were obtained from visual observations, acceleration records, and motion pictures.

"An investigation has been made in the Langley full-scale tunnel of a 47.5 degree sweptback wing-fuselage combination equipped for boundary-layer control by suction. The wing aspect ratio was 3.5, the taper ratio was 0.5, and the airfoil sections normal to the quarter-chord line were NACA 64(sub 1)-A112. The wing configurations tested included the wing with various combinations of extensible leading-edge and split flaps" (p. 1).

Report presenting an investigation to determine the cause for a discrepancy between theoretical and experimental pressure distributions found during a two-dimensional investigation of flapped airfoils in a 2- by 8-inch supersonic tunnel. The results indicated that a tunnel-boundary-layer and model-flow interaction effect on the flow over models mounted directly from the walls in supersonic wind tunnels exists.

Report presenting an experimental and analytical investigation of the flutter of uniform sweptback cantilever wings. The experiments used groups of wings sweptback by rotating and by shearing with angles of sweep ranging from 0 to 60 degrees. Results regarding the experimental investigation and a discussion and comparison of the analytical and experimental results are provided.

Two low-acceleration transonic-flutter vehicles were launched and flown. The first carried two test wings, one of which fluttered at M = 0.92 at a frequency of 61.4 cycles per second. The reference flutter speed determined from two-dimensional theory for an unswept wing in incompressible flow is conservative when compared to the experimental flutter speed. The second vehicle carried two test wings, one of which failed at M = 0.71 because of low-frequency divergent oscillation. Since this failure was not caused by conventional flexure-torsion flutter, no comparison with a reference flutter speed can be made.

Report presenting the effects of changes in Reynolds number on the longitudinal aerodynamic characteristics of a 52 degree sweptback wing with an aspect ratio of 2.88 and NACA 64(sub 1)-112 airfoil sections. The model was tested with the leading edge both smooth and rough. Results regarding force and pitching-moment results, flow observations, and discussion of force and moment characteristics are provided.

Report presenting a study of the flight characteristics of the canard configuration at transonic and supersonic speeds. Known problems concerning the low-speed characteristics of the canard are also investigated.

Report discussing testing on a series of tapered swept wings under conditions simulating rolling flight. The lift, longitudinal-force, and pitching-moment characteristics for three swept wings are provided. The results indicated that a decrease in taper ratio on a swept wing caused a small decrease in damping in roll at low and moderate lift coefficients.

Report discussing the aerodynamic characteristics of three sets of blades over as wide a range of operating conditions as possible. One set of blades was conventional, one had blades that embodied sweep, and one was a nonswept set with thinner blade sections. The sweptback blades were found to be generally inferior to the straight blades, but the Mach numbers tested were not high enough to include speeds that might benefit from sweepback.

From Summary: "Results are presented of an experimental investigation of the characteristics of NACA submerged inlets on a model of a fighter airplane for Mach numbers from 0.30 to 0.875. The effects on the ram-recovery ratio at the inlets of Mach number, angle of attack, boundary-layer thickness on the fuselage, inlet location, and boundary-layer deflectors are shown. The data indicate only a slight decrease in ram-recovery ratio for the inlets ahead of or just behind the wing leading edge as Mach number increased, but showed large decreases at high Mach numbers for the inlets aft of the point of maximum thickness of the wing."

Memorandum presenting the beneficial effects on stability limits and combustion efficiency produced by the application of surfaces immersed in the combustion zone to a ram-jet-type burner. Investigations were made with one, two, three, and four rows of wedges at simulated sea-level and altitude subsonic ram-jet flight conditions. The addition of rows of wedges immersed in the combustion zone regularly extended the stability limits of combustion.

Report presenting control requirements and parameters for a ram jet with a variable-area exhaust nozzle, which have been analyzed from calculated performance charts covering flight Mach numbers from 0.6 to 3.0 and altitudes from sea level to 30,000 feet. Requirements for maximum efficiency, safe and stable operation, maximum range of thrust at a given flight Mach number, and control of fuel flow are discussed and control parameters are selected.

The results of power-off force tests and flight tests of a model with a thin unswept low-aspect-ratio wing are presented. The tests were made with the flaps retracted and deflected. The effects on the lateral flight characteristics of decreasing directional stability were noted.

Report presenting an investigation of icing and ice protection at the inlet of a turbojet engine in the altitude wind tunnel. A method of ice protection was studied that uses hot gas bled from a turbine inlet and injected into the air stream ahead of the compressor inlet. Ice was either prevented or accumulated slowly at various engine speed levels.

Memorandum presenting a correlation of available two-dimensional airfoil data to determine the effects of compressibility on the location of the section aerodynamic center at low lift coefficients. The results indicate that large forward or rearward movements of the aerodynamic center with Mach number are possible.

Report regarding the results of an investigation at high Reynolds numbers and low Mach numbers in the full-scale tunnel to determine the effect of leading-edge high-lift devices and split flaps on the maximum-lift and lateral characteristics of a rectangular wing of aspect ratio 3.4 with circular-arc airfoil section. Results regarding the maximum lift and stalling characteristics on the basic wing, effect of split-flap deflection, effect of leading-edge high-lift devices, and lateral characteristics with the flaps are provided.

Report presenting an investigation to determine the effects of various design parameters on the lateral-stability characteristics of a glider towed by a single towline. The investigation showed that it is possible to obtain inherent lateral stability with a single towline system.

Report presenting an investigation in the pressure wind tunnel to determine the effect of an operating propeller on the aerodynamic characteristics of a model of a vertical-rising airplane with an unswept wing with an aspect ratio of 3. Lift, longitudinal force, pitch, and roll characteristics, with and without power, are presented for the complete model and various combinations of model components.

Report presenting the use of a simplified method of analysis in order to relate the turbine operations for take-off and cruise at rotative speed. This allows turbine velocity diagrams to consider both take-off and cruising operation. Results regarding the two-stage turbine design and the downstream-stator turbine design are provided.

Report presenting a discussion of the flow mechanism in an afterburner extension to a ramjet engine. An experimental evaluation of the operation of 16-inch ramjet equipped with an afterburner at Mach number 1.8 and 2.0 in the supersonic wind tunnel. The experimental data confirmed the proposed method of afterburner operation.

Report presenting foredrag measurements made at zero angle of attack for a series of fineness ratio 3 nose shapes. The types of noses investigated included theoretically derived minimum drag shapes, hemispherically blunted cones, and other more common profiles. Results regarding hemispherically blunted cones, theoretical minimum drag nose shapes, and comparison of foredrag of all the force models are provided.