Abstract. Experimental work was carried out to improve material conversion efficiency and to reduce handling costs inherent in the present process for production of high purity calcium. Charges up to 54 pounds were handled successfully in the equipment available. Material losses were reduced and more complete removal of alkali and alkaline earth metals was effected by controlled pressures of inert gas and by melting under positive pressure of Argon.

A method of calibrating the static-pressure source of a pitot static airspeed installation on an airplane in level flight, dives, and other maneuvers at high altitude and at transonic and supersonic speeds is described. The method principally involves the use of radar-phototheodolite tracking equipment. The various sources of error in the method are discussed and sample calibrations are included.

Report presenting a flight investigation of rocket-powered models at high-subsonic, transonic, and supersonic speeds to determine the zero-lift drag of fin-stabilized bodies of revolution differing in maximum diameter. All bodies had 6.04 fineness ratio and cut-off sterns with equal base area. The most favorable location out of the 20-percent, 40-percent, and 60-percent positions were evaluated for different speeds.

The aerodynamic characteristics of 34 miscellaneous airfoils tested in the Langley two-dimensional low-turbulence tunnels are presented. The data include lift, drag, and in some cases, pitching-moment characteristics, for Reynolds numbers between 3.0 x 10 (exp 6) and 9.0 x 10 (exp 6).

"An investigation was conducted to determine the cause of failures in the seventh- and tenth-stage blades of an axial-flow compressor. The natural frequencies of all rotor blades were measured and critical-speed diagrams were plotted. These data show that the failures were possibly caused by resonance of a first bending-mode vibration excited by a fourth order of the rotor speed in the seventh stage and a sixth order in the tenth stage" (p. 1).

Report presenting data from 95 subsonic flutter tests conducted in the flutter research tunnel on untapered cantilever wings with sweepback angles of 0, 45, and 60 degrees and carrying a single concentrated weight. The primary purpose of the investigation was to present experimental information to be used to evaluate analytical procedures for determining the flutter speed of weighted sweptback wings. The dynamic pressure, flutter velocity, Mach number, natural and flutter frequencies, and phase-angle relationships of the stresses for the natural and flutter frequencies are presented.

"An experimental investigation, using microscopic observation and color motion photomicrographs of the action, was conducted to determine the cause of fretting. Glass and other noncorrosive materials, as well as metals, were used as specimens. A very simple apparatus vibrated convex surfaces in contact with stationary flat surfaces at frequencies of 120 cycles or less than l cycle per second, an amplitude of 0.0001 inch, and load of 0.2 pound" (p. 135).

"High-speed wind-tunnel tests were conducted of two versions of a 0.17-scale model of the McDonnell XF2H-1 airplane to ascertain the high-speed stability and control characteristics and to study means for raising the high-speed buffet limit of the airplane, The results for the revised model, employing a thinner wing and tail than the original model, revealed a mild diving tendency from 0.75 to 0.80 Mach number, followed by a marked climbing tendency from 0.80 to 0.875 Mach number. The high-speed climbing tendency was caused principally by the pitching-moment characteristics of the wing" (p. 1).