Carpet plots included permit the selection of the blade camber and the design angle of attack required to fulfill a design vector diagram. Other carpet plots provide means for the prediction of off-design turning angles.

A report in two parts: one is a brief review of methods available to helicopter designers for obtaining desired stability characteristics by modifying airframe design and the other is a review of some of the methods of predicting rotor stability derivatives.

From Summary: "Data from ditching investigations conducted at the Langley Aeronautical Laboratory with dynamic scale models of various airplanes are presented in the form of tables. The effects of design parameters on the ditching characteristics of airplanes, based on scale-model investigations and on reports of full-scale ditchings, are discussed. Various ditching aids are also discussed as a means of improving ditching behavior."

Report presenting an investigation in the high-speed 7- by 10-foot tunnel to determine some effects of tail height and wing plan form on the static longitudinal stability characteristics of a complete, small-scale model at high subsonic speeds. It had both a low-tail and high-tail position. Results regarding the lift and drag characteristics and longitudinal stability characteristics are provided.

Report presenting results from pitot-static and hot-wire anemometer surveys at low speed of the flow over a thin, sharp-edge airfoil which simulated a flat plate. The primary purpose was to obtain detailed measurements of the flow associated with the so-called thin-airfoil type of stall. Results regarding the preliminary tests, pressure distributions, mean flow measurements, velocity fluctuation measurements, and observations and measurements of the flow in the immediate vicinity of the leading edge are provided.

"Slender-body theory is used in conjunction with late theory to analyze the static aeroelastic-divergence behavior of low-aspect-ratio rectangular wings of constant thickness when chordwise deformations are considered. In the analysis, the spanwise variation of the deflection is restricted to a parabola but the chordwise variation is allowed complete freedom. Results show the variation of the divergence speed and mode shape with the aspect ratio" (p. 1).

Note presenting a qualitative approach to the problem of the effect of frequency and temperature on fatigue, as the theoretical and experimental results do not always seem to match. The fatigue problem is examined from the viewpoint of a two-component system.

Note presenting a study of Stokes' stream function for subsonic or supersonic flow past axisymmetric bodies of small slope. The first-order equation is found to be nonlinear. It can be linearized if one seeks only the formal order of accuracy of the slender-body approximation.

Report presenting a description of a new blade series designed to operate at near choking inlet Mach numbers and to have near maximum critical Mach numbers by employing high aerodynamic loading of the profiles in the leading-edge region. Results regarding aerodynamic characteristics and prediction of high-speed performance are provided.

Report presenting a method for calculating the expected number of maxima or minima of a random process with non-Gaussian frequency distribution from the statistical moments of the process and its first two derivatives. The effects of skewness and kurtosis can also be calculated provided the required moments are known.

"Pressure-distribution and force tests of a circular cylinder have been made in the Langley 11-inch hypersonic tunnel at a Mach number of 6.88, a Reynolds number of 129,000, and angles of attack up to 90 degrees. The results are compared with the hypersonic approximation of Grimminger, Williams, and Young and a simple modification of the Newtonian flow theory. An evaluation of the crossflow theory is made through comparison of present results with available crossflow Mach number drag coefficients" (p. 1).

From Summary: "Charts are developed for the analysis of flow in a whirling constant-diameter duct. These charts permit the determination of the duct-exit Mach number, or the Mach number at any point along the duct, for practical ranges of duct-inlet Mach number, duct-tip Mach number, friction factor, ratio of ambient temperature to duct-flow total temperature, ratio of duct-tip radius to duct hydraulic diameter, and heat conductivity through the duct wall and surrounding material. The method of using the charts is illustrated through the computation of a sample problem."

Report presenting an investigation in the high-speed hydrodynamics facility to determine whether planing lift coefficient of a flat-bottom planing surface remains constant with increasing speed at the high towing speeds obtainable. The generally accepted assumption that there is no effect of speed on the lift coefficient of positive-pressure lifting surfaces is valid at least up to 170 fps.

Note presenting flight investigations of single-axis attitude stabilization during low-speed instrument approaches. A single-rotor helicopter that had been modified to include an electronic control system was used in the investigation. Results regarding heading stabilization, pitch stabilization, and roll stabilization are provided.

Report presenting an investigation at Mach number 2.40 to determine the aerodynamic characteristics of plain overhang balances on flap-type controls. Testing was performed on a two-dimensional wing with three trailing-edge flaps with balance lengths of 38, 60, and 82 percent of the flap chord. The effect of wing-flap gap size were investigated for the flap with 38 percent balance.

Report presenting an experimental investigation in the flutter research tunnel on the oscillating forces and moments on a two-dimensional wing equipped with an oscillating circular-arc spoiler.

"The similarity rules for linearized compressible flow theory (Göthert's rule and its supersonic counterpart) are extended to second order. It is shown that any second-order subsonic flow can be related to "nearly incompressible" flow past the same body, which can be calculated by the Janzen-Rayleigh method" (p. 1).

Report presenting calculations of the lift and moment responses to penetration of sharp-edged traveling gusts for wings in incompressible and supersonic two-dimensional flow, for wide delta and rectangular wings in supersonic flow, and for very narrow delta wings. The results of the calculations indicate that the forward speed of the gusts has a large effect on the lift- and moment-response functions.

Report presenting a study of the use of a magnetic field to control the motion of electrically conducting fluids. Results indicated that the skin friction and heat-transfer rate are reduced when the transverse magnetic field is fixed relative to the plate and increased when fixed relative to the fluid.

From Summary: "A simple inelastic collision model of meteor-atmosphere interaction is used and analytic relations for velocity, deceleration, size, and relative luminous magnitude of meteors are derived and expressed in dimensionless parametric form. The analysis is compared with available quantitative observations of meteor behavior and it is indicated that a large fraction of the atmospheric bombardment energy is used in eroding meteor material. The erosion from large, high-speed vehicles as they traverse the high-altitude, free-molecule portion of the atmosphere is calculated, on the assumption that the vaporization process is similar to that which occurs for meteors."

The test method presented shows that the "toss energy" contributed by the apparatus for brittle materials is negligible. The total toss energy is considered to consist of two components: (a) recovered stored elastic energy and (b) kinetic energy contributed directly by the apparatus. The results were verified by high-speed motion pictures of the test in operation.

Report presenting equations, tables, and figures for use in the analysis of helium flow at supersonic and hypersonic speeds. Tables are provided for useful dimensionless ratios for continuous one-dimensional flow and normal-shock waves as functions of Mach number. The oblique-shock characteristics of wedges and cones in helium at various Mach numbers are also presented.

Note presenting the equations of the compressible laminar boundary layer for the windward streamline in the plane of symmetry of a yawed cone. Solutions are obtained for both insulated and cooled surfaces. The heat-transfer rate to this most windward streamline increases significantly with angle of attack.

From Summary: "Three-dimensional views are presented of the first three natural vibration mode shapes of ten cantilever-wing models. A table of normalized deflections at six spanwise and five chordwise stations is included for each mode. These mode shapes were measured by a rather unique experimental technique using grains of sand as accelerometers."