Note presenting an investigation of the influence of the wheel drag on the performance of the landing gear. The differential equations are developed and solved by numerical integration and by an analytical method. The possibilities of an eccentric wheel and an inclined shock strut are considered.

Aerodynamic coefficients similar to those of the isolated airfoil are obtained as functions of the cascade geometry and the phasing between successive blades; the phasings considered are zero, 90 degrees, and 180 degrees. These aerodynamic coefficients are plotted for the special case when all the airfoils are vibrating in bending in phase (360 degree phasing). It is shown that the effect of cascading for this case is to reduce greatly the aerodynamic damping.

Note presenting a study of certain features of transverse resonance in an idealized combustion chamber. Modes of weak oscillation are described with average Mach number neglected but with the effect of axial gradient of mean temperature considered. The nature of finite transverse periodic waves is also analyzed.

Report presenting the results of tension and compression tests on 3S aluminum alloy sheet presented together with values of Poisson's ratio in the plastic range.

Note presenting an investigation of the effect of prerotation on the wheel spin-up drag loads on a small landing gear during landings by means of tests in the impact basin. A series of simulated landings with various amounts of prerotation was made with a dropping weight of 2500 pounds and a forward speed of 85 fps at a strut angle of 15 degrees. The results indicated that for horizontal velocities up to at least 85 fps, prerotatoin, even partial prerotation, appears to be a practical method for obtaining appreciable reductions in the spin-up drag loads.

Report presenting the use of a droplet camera developed at the NACA Lewis laboratory to obtain drop-size distribution and drop-velocity data for isooctane injected from a simple orifice directly into a turbulent air stream. Vaporization and drag coefficients were calculated for isooctane drops accelerating and evaporating in streams with velocities of 140 and 180 feet per second. Results regarding the vaporization-rate equations, drop-size-distribution analyses, analysis of drop-velocity data, and fuel-spray-evaporation calculations are provided.

Report presenting pressure and scattered-light measurements in the 11-inch hypersonic tunnel to determine the effect of stagnation temperature on the flow in two Mach number 7 nozzles and to determine the nature of the condensation process occurring at low stagnation temperatures. Results regarding the static-pressure measurements, Mach number effect, particle size and concentration, and general discussion are provided.

Note presenting an evaluation of an accelerometer method for obtaining landing-gear drag loads for a series of landings with a small landing gear. Drag loads were obtained from time histories of angular acceleration of the wheel, the moment of inertia, and the deflected tire radius.

Report presenting a calculation of subsonic span loads and the resulting stability derivatives for a systematic series of vertical- and horizontal-tail combinations in sideslip and in steady roll in order to provide information embracing a wide range of probable tail configurations. The results of this investigation, which had a wide range of geometric variables than previous studies, showed trends which were in general agreement with the results of previous investigations.

Note presenting transition tests made in free-flight on a slender body of revolution at a Mach number of 3.5, wall to free-stream temperature ratio of unity, and with a noiseless and zero-turbulence air stream. The parameter which was varied was surface roughness.