Report on an investigation to determine the erect and inverted spin and recovery characteristics of a model of the North American FJ-4 airplane. The testing found that either a flat-type of steep-type spin may be obtained when the airplane is spinning erect. The optimum recovery technique from inverted spins was full rudder reversal with simultaneous movement of the ailerons to full with the stick maintained full forward.

Memorandum presenting a transonic flutter investigation of models of the all-movable horizontal tail of a fighter airplane in the transonic blowdown tunnel. The models were dynamically and elastically scaled by criteria which provide a flutter safety margin. Results regarding some general comments, simulated airplane tests, effects of pitch stiffness with rearward pitch axis, and effect of pitch-axis location are provided.

Report issued by the Bureau of Mines investigations of "converting small particle lignite to a stable, storable fuel of relatively high heating value" (p. 1). The equipment and methods used for the study are presented. This report includes tables, maps, illustrations, and photographs.

Report presenting the low-speed yawed-rolling characteristics of two 40 x 12, 14-ply-rating, type VII aircraft under straight-yawed rolling over a range of inflation pressures and yaw angles for two vertical loadings. Static testing was performed to determine the vertical, lateral, torsional, and fore-and-aft elastic characteristics of tires. Measured lateral and torsional spring constants appeared to decrease with increasing amplitude of tire lateral distortion or twist.

Report presenting an experimental investigation to determine the effects of shroud-lip radius of curvature, shroud length, and shroud diffuser angle on the static thrust characteristics of a small-scale shrouded propeller which simulated a propeller submerged in the wing of an airplane. Results regarding the effect of propeller blade angle, effect of lip radius, effect of propeller location in shroud, effect of shroud length behind the propeller plane, effect of diffuser angle, and effect of ground proximity are provided.

"An analysis, based on the linearized thin-airfoil theory for supersonic speeds, of the wave drag at zero lift has been carried out for a simple two-body arrangement consisting of two wedgelike surfaces, each with a rhombic lateral cross section and emanating from a common apex. Such an arrangement could be used as two stores, either embedded within or mounted below a wing, or as auxiliary bodies wherein the upper halves could be used as stores and the lower halves for bomb or missile purposes. The complete range of supersonic Mach numbers has been considered and it was found that by orienting the axes of the bodies relative to each other a given volume may be redistributed in a manner which enables the wave drag to be reduced within the lower supersonic speed range (where the leading edge is substantially subsonic)" (p. 1).

Note presenting the stress-rupture properties of commercially pure nickel at 1500 degrees Fahrenheit as determined for its application as a container material for molten sodium hydroxide. Stress-rupture tests of L-nickel tubes containing sodium hydroxide were run with atmospheres of air or argon external to the tubes. Sodium hydroxide was found to have little effect on the stress-rupture strength of nickel tubes tested in argon at 1500 degrees Fahrenheit for times up to 200 hours.

"The momentum integral equations are derived for the boundary layer on an arbitrary curved surface, using a streamline coordinate system. Computations of the turbulent boundary layer on a slightly yawed cone are made for a Prandtl number 0.70, wall to free-stream temperature ratios of 1/2, 1, and 2, and Mach numbers from 1 to 4. Deflection of the fluid in the boundary layer from outer stream direction, local friction coefficient, displacement surface, lift coefficient, and pitching-moment coefficient are presented" (p. 1).

Note presenting a method for solving problems associated with Laplace and Poisson equations which, in general, requires considerably fewer equations than the usual methods and which gives a convergent solution by the method of successive approximations.

Note presenting an experimental investigation to study the feasibility, from considerations of lateral trim, of having all the propellers of a tilting-wing vertical-take-off-and-landing (VTOL) airplane rotate in the same direction since this is a desirable feature from practical considerations. The model was a wing with four propellers, the slipstream from which covered practically the entire span of the wing. Results regarding basic data and application of the data are provided.

Report presenting a flight investigation at subsonic speeds to improve the damping of lateral oscillations by means of a viscous damping cylinder in the rudder system in conjunction with adjusted hinge-moment parameters. A highly geared balancing tab was also added to the rudder. Results regarding the original configuration and three different levels of modification are provided.

Note presenting a theoretical treatment for determining lift and moment on thin arrowhead or pointed-tip wings of which the delta plan form is a special case with an unswept trailing edge. Expressions have been developed for the section and total forces and moments to the third power of the reduced frequency. Sample results are given in the form of curves to show that retention of terms to the third power of the frequency gives good accuracy over a range of frequency that covers many practical flutter applications.

A method is presented for the calculation of lift coefficients for rectangular lifting surfaces of aspect ratios from 0.125 to 10 operating at finite depths beneath the water surface, including the zero depth or planing condition. Theoretical values are compared with experimental values obtained at various depths of submergence with lifting surfaces of aspect ratios from 0.125 to 10. The method can also be applied to hydrofoils with dihedral. Lift coefficients computed by this method are in good agreement with existing experimental data for aspect ratios from 0.125 to 10 and dihedral angles up to 10 degrees.

Note presenting a study of the corrosion resistance of 11 nickel-base compositions to molten sodium hydroxide at 1500 and 1700 degrees Fahrenheit in order to find a container material for the caustic at these temperatures. Results are provided for the solid-solution alloys, nickel with mechanically dispersed second phase materials, and the precipitation-hardened alloy.

Report presenting an experimental investigation of turbojet engine performance with several configurations of interacting multiple-loop controls in order to determine the ideal mode of control for optimum rotor speed and turbine-discharge temperature during thrust increase and afterburner ignition conditions.

Report presenting a theoretical analysis of air flow in a channel in which oxygen dissociation and recombination occur. An investigation is also made of the comparative relaxation times of the oxygen dissociation-recombination reaction in relation to molecular vibrations.

From Introduction: "In the present report, consideration is given to certain features intended to improve the accleration-limiting characteristics of a normal-accleration control system."

Report presenting a wind-tunnel investigation to determine the static longitudinal stability and trim characteristics of a sweptback-wing jet-transport model equipped with an external-flow jet-augmented flap. Tests were also conducted to determine the effects of wing position, vertical position of the horizontal tail, and size of the horizontal tail.

Report presenting six-percent-thick NACA 63-series compressor-blade sections with a loaded-leading-edge mean line investigated systematically in a two-dimensional porous-wall cascade over a range of Reynolds numbers. Blades cambered to have four different isolated-airfoil lift coefficients were tested over the usable angle-of-attack range at four different inlet-air angles and two different solidities.

Note presenting the aerodynamic characteristics of several noncircular two-dimensional cylinders with axes normal to the stream at various flow incidences for a range of Reynolds numbers as determined from low-speed wind-tunnel tests. The results indicate that these parameters have large effects on the drag and side force developed on these cylinders. Results regarding drag of two-dimensional cylinders, side force developed on two-dimensional cylinders, and directional stability and spinning characteristics of three-dimensional bodies are provided.

Report presenting an investigation of the effects of high temperatures incurred at hypersonic speeds using an ethylene-heated high-temperature jet.

Note presenting an investigation performed in the high-speed 7- by 10-foot tunnel to determine the rolling derivatives for swept wing-body configurations at angles of attack from 0 to 13 degrees and at high subsonic Mach numbers. Results regarding experimental rolling derivatives and estimations of rolling derivatives are provided.

"Calculations have been made of the initial portion of the boundary of axisymmetric free jets exhausting at large pressure ratios from a conically divergent nozzle having a jet exit Mach number of 2.5 and a semidivergence angle of 15 degrees. The results of the calculations indicate the size and shape of the jet to be expected at large pressure ratios, the effects of ratio of specific heats, and the large initial inclinations of the boundary that are likely to be encountered by hypersonic vehicles at high altitude" (p. 1).

Report presenting overall sound-pressure levels and frequency spectra under static conditions from a modified supersonic propeller designed to operate efficiently at a high forward speed without the high noise levels associated with the supersonic propeller. The three-blade, 10-foot-diameter, 1700-rpm propeller is powered by a turbine engine and is designed to operate at a Mach number of 0.95 at 40,000 feet.