"A method is presented for the computation and graphic representation of a series of possible turbine designs for any specific application. The use of a preliminary design chart is suggested for determining the number of stages and the effects of exit whirl and annular-area divergence on possible configurations. A specific design chart can then be made to aid in the study of the relations between turbine radius ratio, diameter, and significant design parameters such as Mach numbers, turning angles, and blade root stresses" (p. 1).

Note presenting a consideration of a wing-selection problem sometimes encountered in the preliminary design of supersonic airplanes and missiles. The problem is to determine the span, section thickness ratio, and skin thickness or hollowness ratio of the wing of least drag when the plan form, section shape, wing lift requirement, and flight conditions are assumed known. An example of the application of the method to a diamond wing at Mach number 2.0 for a range of specified flight conditions is presented.

The charts presented give the compressive buckling coefficients for a single-truss-core and a double-truss-core sandwich plate. These charts cover a wide range of sandwich proportions and may be used for sandwiches with unequal faces. They apply to inplane compressive loads acting parallel or perpendicular to the core direction or for various combinations of these loads. (author).

"Charts giving the compressive-buckling stress coefficients for sheet panels of a shape occurring in swept-wing plan forms are presented. The panels are assumed to be a part of a continuous flat sheet divided by nondeflecting supports into parallelogram-shaped areas. The stability analysis was performed by the energy method and the results show that, over a wide range of panel aspect ratio, such panels are decidedly more stable than equivalent rectangular panels of the same area" (p. 1).

"An experimental determination of the critical bending moment of a box beam stiffened by posts is described and discussed. The experimental buckling load is in good agreement with that given by theory. Since appreciable distortion of the beam cross section occurred before the buckling load was reached, modification of post construction by the use of several ribs may be necessary for maintenance of the rectangular shape of the cross section" (p. 1).

Note presenting testing of twenty-seven structural joint specimens of 2024-T3 and 2024-T4 aluminum alloy consisting of a T-stringer riveted to a 10- by 10-inch skin surface under simulated aerodynamic heating with no external loading applied. Rivet size and pitch were found to influence the conductance but the rivet materials tested had no observable effect.

"Theoretical buckling stresses are determined in explicit form for circular cylinders with circumferential and axial stiffening. The loadings are axial compression, radial pressure, hydrostatic pressure, and torsion. Analyses were confined to moderate-length and long cylinders" (p. 1).

"The local buckling of stiffener sections and the buckling of plates with sturdy stiffeners are reviewed, and the results are summarized in charts and tables. Numerical values of buckling coefficients are presented for longitudinally compressed stiffener sections of various shapes, for stiffened plates loaded in longitudinal compression and in shear, and for stiffened cylinders loaded in torsion. Although the data presented consist primarily of elastic-buckling coefficients, the effects of plasticity are discussed for a few special cases" (p. 1).

"The local buckling of stiffener sections and the buckling of plates with sturdy stiffeners are reviewed, and the results are summarized in charts and tables. Numerical values of buckling coefficients are presented for longitudinally compressed stiffener sections of various shapes, for stiffened plates located in longitudinal compression and in shear, and for stiffened cylinders loaded in torsion. Although the data presented consist primarily of elastic-buckling coefficients, the effects of plasticity are discussed for a few special cases" (p. 1).

"A comprehensive review of failure of stiffened curved plates and shells is presented. Panel instability in stiffened curved plates and general instability of stiffened cylinders are discussed. The loadings considered for the plates are axial, shear, and the combination of the two. For the cylinders, bending, external pressure, torsion, transverse shear, and combinations of these loads are considered" (p. 1).

Note presenting an investigation of the instability of flow from two ducts that join into a common duct and of the influence of the various parameters on the phenomenon. A two-dimensional potential analysis was carried out under the assumption that the two ducts discharge into a region of constant pressure.

Report presenting the use of linearized theory for compressible unsteady flow to treat the problem of a partial-span rectangular control surface hinged at its leading edge and mounted on a rectangular wing, oscillating in supersonic flow. The motions of the wing-aileron configuration are assumed to consist of vertical translation, pitching, and aileron rotation. Results regarding the spanwise aerodynamic effects and application to flutter are provided.

Note presenting the results of spin-tunnel investigations compared with corresponding full-scale results for 60 different airplane designs. The purpose of the comparison was to determine the reliability of the model results in predicting full-scale spin and recovery characteristics. Results regarding the recovery characteristics, angle of attack, rate of rotation, altitude loss per revolution, angle of wing tilt, and emergency spin-recovery parachutes are provided.

"Results are presented of an investigation to determine the effect of boundary-layer displacement and leading-edge bluntness on surfaces in hypersonic flow. The presence of the boundary layer and the blunt leading edge induce pressure gradients which in turn affect the skin friction and heat transfer to the surface. Methods for predicting these phenomena on two-dimensional surfaces are given and a brief review of recent three-dimensional results is presented" (p. 1).

Note presenting a comprehensive review on the method of split rigidities. The principles on which the method is based are discussed and it is shown how these principles are applied. The method is applied to several examples of using this method to calculate buckling stresses of structures that buckle in composite modes.

Results are presented of a wind-tunnel investigation to determine influence of the fuselage and tail on static stability and rotary derivatives in roll of a model having 45 degrees sweptback wing and tail surfaces. The wing alone and the model without the horizontal tail showed marginal longitudinal stability near maximum lift. The longitudinal stability of the complete model was satisfactory. The vertical tail produced larger increments of rate of change of lateral-force and yawing-moment coefficients with wing-tip helix angle than the fuselage or the horizontal tail.

Note presenting the velocity potentials, span loadings, and corresponding force and moment derivatives for a number of slender-tail arrangements performing a steady rolling motion at supersonic speeds. The method of analysis is based on an application of conformal-transformation techniques.

Note presenting experimental results that verify an analysis of errors occurring when thermocouples are used to measure the temperature of surfaces exposed at temperatures different from that of the surface. The data indicate that the electrical insulation of the wires is not effective in reducing the errors involved when the thermocouples are placed normal to the surface and exposed to the ambient fluids.

Report presenting turbulent-heat-transfer measurements obtained through the use of an axially symmetric annual nozzle consisting of an inner shaped center body and an outer cylindrical sleeve at Mach number 3.90. Results regarding the variation of wall temperature with longitudinal distance, variation of local Nusselt number with local Reynolds number, and variation of local temperature-recovery factor with local Reynolds number are provided.

Report present a study of the problem of determining nonlinear parameters of dynamic systems, such as aircraft or servomechanisms, whose measured responses are nonlinear. Nonconstant coefficients can be determine satisfactorily for first- or second-order systems using one or a combination of the techniques developed. The methods can be divided into three categories: the equations-of-motion methods, the response curve-fitting methods, and the phase-plane methods.

Report presenting surface temperature distributions on a hollow cylinder aligned with the airstream was studied in a Mach 3.12 wind tunnel at a range of Reynolds numbers. Transition with and without single roughness elements was observed from surface temperature distributions and high-speed schileren motion pictures. Results regarding pressure distributions, recovery-factor distributions, high-speed schileren motion pictures, transition Reynolds number, heat-conduction effects, and a qualitative description of observed flows are provided.

Experimental and theoretical results are presented for boundary layer studies consisting of Schlieren observations and momentum surveys made on hollow cylinder models with their axes aligned parallel to the stream. Results were obtained for three model diameters and for natural and artificially induced turbulent boundary layer flows.

The trajectories of droplets in the air flowing past an NACA 65AO04 airfoil at an angle of attack of 8 deg were determined. The amount of water in droplet form impinging on the airfoil, the area of droplet impingement, and the rate of droplet impingement per unit area on the airfoil surface were calculated from the trajectories and presented to cover a large range of flight and atmospheric conditions. These impingement characteristics are compared briefly with those previously reported for the same airfoil at an angle of attack of 4 deg.

Wind-tunnel tests were conducted to determine the ground effects on a tailless model with a wing of aspect ratio 2 and infinite taper, and on a tailed model with a triangular wing of aspect ratio 3, with flaps. Control-surface hinge moments were measured on the tailless model. The results are compared with the predictions of the theory of Tani, et al.