"A solution based upon small-deflection theory is presented for the critical shear stress of curved rectangular panels with simply supported edges. Computed curves which cover a wide range of panel dimensions are presented; these curves are found to be in good agreement with test results. Estimated curves are also given for panels with clamped edges" (p. 1).

Note presenting a method for the calculation of bending stresses due to torsion in a tapered box beam. A special taper was assumed in which all flanges, if extended, would meet at a point. The results obtained by this method were compared with experimental data obtained from tests performed on a tapered box beam.

Report presenting an investigation of the effects of several spoiler arrangements on the spanwise variation of section twisting moments of a wing of NACA 230-series airfoil sections. Both plain and perforated spoilers were tested at a designated Mach and Reynolds number and force and moment measurements as well as chordwise pressure-distribution measurements at six spanwise stations were obtained.

Wing was tested with full-span, partial-span, or split flaps deflected 60 Degrees and without flaps. Chordwise pressure-distribution measurements were made for all flap configurations.. Peak values of maximum lift coefficient were obtained at relatively low free-stream Mach numbers and, before critical Mach number was reached, were almost entirely dependent on Reynolds Number. Lift coefficient increased by increasing Mach number or deflecting flaps while critical pressure coefficient was reached at lower free-stream Mach numbers.

Report presenting a proposal for the isosceles triangle twisted into a screw surface about its axis as a propeller for transonic flight speeds. The purpose is to attain the drag reduction associated with a large sweepback in a structurally practicable configuration.

Note presenting a wind-tunnel investigation of the effect of span, spanwise location, and chordwise location of spoilers on the lateral control characteristics of an unflapped semispan wing equipped with a simple spoiler with a projection 5 percent of the chord. The chordwise investigation involved moving a 50-percent-semispan spoiler from the 50-percent-chord station to the 80-percent-chord station. Results regarding the plain-wing characteristics, spanwise investigation, and chordwise investigation are provided.

Report presenting wind tunnel measurements of the air load distribution on a canard-type model. Two combinations of lifting surface and fuselage were obtained by removing the wing and stabilizer of the model. Results regarding the fuselage pressure distribution, spanwise loading curves, and variation of lift, drag, and pitching-moment coefficients with angle of attack are provided.

Report presenting tests of a modified NACA 65(sub 1)-012 airfoil with a 30-percent airfoil-chord flap with contours simulating various distorted surface-covering shapes for the purpose of investigating practicability of reducing distortion effects to a negligible amount by maintaining an undistorted contour over a small part of the flap chord.

Note presenting an investigation to determine the effect of variations in the lateral-stability derivatives, wing loading, altitude, and radii of gyration on the combination of directional stability and effective dihedral required for lateral stability at the landing and cruising condition. The results of the investigation showed that an airplane with a high wing loading designed for high-speed and high-altitude flight would be laterally stable if the moments of inertia, the location of the principal longitudinal axis of the airplane, and the value of the damping-in-roll derivative were properly selected.

"A description is presented of the Langley two-dimensional low-turbulence pressure tunnel and a history is given of the work done at the Langley Memorial Aeronautical Laboratory which led to the achievement of a remarkably low level of turbulence in the air stream of this wind tunnel. The types of investigations to which the tunnel is suited and the methods of obtaining and correcting data are also discussed" (p. 1).

Report presenting an investigation made in the 300 mph 7- by 10-foot tunnel to determine at low speed in the longitudinal stability characteristics of a 60 degree sweptback, tapered, low-drag wing of aspect ratio 2.55. The results show undesirably large changes in the longitudinal stability characteristics of the 60 degree sweptback wings.

Report presenting tests to determine the low-speed stability, damping-in-roll, and stall characteristics of five wings, three wings with 42 degrees sweepback and aspect ratio 5.9, 3, and 2, and tow wings with 33 degrees sweepforward and aspect ratios of 5.9 and 3. The results showed that the wings of aspect ratio 5.9 were longitudinally unstable at the stall but that reducing the aspect ratio tended to eliminate the instability.

Report presenting power-off flight tests in the free-flight tunnel to determine the dynamic stability characteristics of an airplane model with a 42 degree sweptback wing of aspect ratio 5.9 and taper ratio 0.5. The static-stability and wing-stall characteristics of the model were also determined. Results regarding force tests, flow surveys, and flight tests are provided.

Report presenting a flight investigation in the free-flight tunnel to determine the severity of the dynamic stability and control problems associated with 62 degrees sweepback. In addition to the flight tests, force tests and tuft tests were made to determine the static-stability and wing-stall characteristics, and calculations were made to determine the boundary of zero damping of the lateral oscillation.

Report presenting an investigation of the forward-flight performance characteristics of a typical single-rotor helicopter equipped with main and tail rotors. Testing occurred over a range of tip-speed ratios and thrust coefficients. Results regarding the fuselage effects and rotor characteristics are provided.

Note presenting an investigation of the knock ratings of aliphatic hydrocarbons, pure paraffins and olefins prepared in quantities sufficient for engine tests. The report describes the methods of preparation and purification of three pentanes, four hexanes, three heptanes, four octanes, eight nonanes, seven decanes, four hexenes, five octenes, six nonenes, six decenes, and a number of alcohols, ketones, esters, and alkyl halides.

Note presenting a determination of friction coefficients for three constant-area vaneless diffusers, used in conjunction with a centrifugal impeller, from static- and total-pressure surveys taken at several radii and from the usual overall measurements of temperature, pressure, and air flow. The average value of the friction coefficient through the entire diffuser was approximately 50 percent higher than that for fully developed turbulent flow in smooth pipes.

Report presenting calculations of the supersonic wave drag at zero lift for a series of wings with thin symmetrical biconvex sections with untapered plan forms and various angles of sweepback and aspect ratios.

Report presenting a procedure for obtaining the pressure distribution in a two-dimensional, incompressible, and nonviscous flow on an arbitrary airfoil section in cascade.

Report presenting a set of equations based on the first mode of wing bending for determining the dynamic responses of an airplane wing structure as induced by gusts. The representation of the airplane is such that the aerodynamic damping of the vibratory motion of the wing is separate from that of the vertical motion of the airplane as a whole.

Note presenting an application of the iterative interference method to three problems concerning the design of cascades. The three problems considered include the determination of the shape and setting of thin blades with a prescribed type of vortex distribution, determination of the shape and setting of thin blades with certain prescribed types of pressure distributions, and determination of the blade setting for a cascade of given airfoil shape and solidity.

Note presenting an investigation of three centrifugal impellers, the same except for angular blade curvature, to determine the effect of the distribution of blade loading on impeller performance. Results regarding impeller efficiency, energy addition and pressure ratio, flow characteristics, and operating range are provided.

Report presenting data for alloys that can resist temperatures up to 1350 degrees Fahrenheit so that they can be used in gas turbines. The chromium-base alloys currently have certain severe limitations in their present state of development. However, considerable progress has been made in overcoming these difficulties and further improvement seems possible.

Report presenting an investigation of the possibility of developing an airfoil to carry lift without decreasing the critical Mach number below that of the basic thickness form at zero lift. Low-speed testing of five NACA 66-series airfoil sections with a thickness-chord ratio of 0.16 was carried out in the two-dimensional low-turbulence pressure tunnel. Results regarding the design lift coefficient, maximum lift coefficient, low-drag range, and pitching-moment coefficients are provided.