From Introduction: "This report presents the aerodynamic characteristics at low speed end high Reynolds number as determined in the Ames 40- by 80 foot wind tunnel."

Report presenting an investigation of a 24-inch-diameter rotor for a supersonic axial-flow compressor in air up to an actual tip speed of 1654 feet per second and a maximum equivalent tip speed of 1765 feet per second. Results regarding overall performance, rotor-inlet characteristics, rotor-passage flow characteristics, and rotor-outlet characteristics are provided.

Report presenting the results of a preliminary experimental flutter investigation of widely different unswept cantilever wings at Mach number 1.3. Wings with a variety of mass-density parameters, center-of-gravity positions, and elastic-axis positions were tested.

Report discussing an investigation of two sweptback wings of different plan form in order to determine the effects of adding a triangular area to the inboard section of a conventional sweptback wing as a way to create a wing with two stages of sweepback. Lift, drag, and pitching-moment characteristics are provided for a range of Mach numbers.

Report presenting a study of the flight characteristics of the canard configuration at transonic and supersonic speeds. Known problems concerning the low-speed characteristics of the canard are also investigated.

Memorandum presenting preliminary tests in order to determine the effect of forced ventilation on the hydrodynamic characteristics of a scale model of a streamline fuselage of a hypothetical transonic airplane. The forced ventilation consisted of air ejected at about 300 feet per second through small orifices distributed over the fuselage bottom in a series of patterns simulating chines or multiple steps. Results regarding resistance, effective hydrodynamic lift, trim, spray, and air flow are provided.

Report presenting an investigation at subsonic and transonic speeds in the high-speed 7- by 10-foot tunnel to determine the aerodynamic characteristics of a 42.7 degree sweptback wing with a 20-percent-chord and 50-percent-span outboard aileron. The investigation was performed in transonic flow over a bump on the tunnel floor and in subsonic flow on one of the tunnel side walls.

Report presenting an investigation of the effect of the rate of change of angle of attack on the maximum lift coefficient of a pursuit airplane equipped with a low-drag-type wing in stalls of varying abruptness over a range of Mach and Reynolds numbers. Maximum lift coefficients were found to increase linearly with increasing rate of change of angle of attack per chord length of travel up to the maximum rate attained in the tests.

"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).

Memorandum presenting measurements of some of the high-speed characteristics of the D-558-1 airplane up to Mach number 0.89. The results of the tests showed that the stabilizer incidence drastically affected the longitudinal trim characteristics above a Mach number of 0.80.

Memorandum presenting an investigation to determine the automatic lateral stability characteristics of a model equipped with a gyro stabilizing unit that gave response to bank and yaw. Stable flights were obtained with the flicker-type automatic control, and the amplitude of the oscillations was decreased by adding the attachment which provided hunting control.

Measured values of lift, drag, and pitching moment at a Mach number of 1.53 and Reynolds numbers of 0.31, 0.62, and 0.84 million are presented for a wing-fuselage combination having a wing leading-edge sweep angle of 63 degrees, an aspect ratio of 3.42, a taper ratio of 0.25, and an NACA 64A006 section in the stream direction. Data are also presented for sweep angles of 57.0 degrees, 60.4 degrees, 67.0 degrees, and 69.9 degrees. The experimentally determined characteristics were less favorable than indicated by the linear theory but the experimental and theoretical trends with sweep were in good agreement. Boundary-layer-flow tests showed that laminar boundary-layer separation was the primary cause of the differences between experiment and theory.

Report presenting a survey of the present status of research on boundary-layer control and its possible applications in aeronautics. The applications considered include reduction of profile drag by the elimination of turbulent separation, increase of the maximum lift coefficient through control of separation, use of suction and blowing slots near the trailing edge of the airfoil as a means of lateral control, use of boundary-layer control as a means of increasing the efficiency of diffusers and bends, and the use of boundary-layer control to influence shock-boundary-layer interaction at high speeds.

Report presenting a wind-tunnel investigation to determine the effect of propeller operation on the characteristics of submerged inlets. The tests were performed with a model of a hypothetical fighter airplane powered by a turbine-propeller unit. The propeller had eight blades with thin airfoil shanks and dual rotation and the submerged inlets were placed in the fuselage behind the propeller and forward of the wing.

Memorandum presenting stability and control data from the X-4 airplane during the Northrop conducted acceptance tests. The data were obtained for a center-of-gravity position of about 22 percent of the mean aerodynamic chord. Results of the flight indicated that the airplane is slightly unstable, stick fixed, in gear-up, flaps-up configuration for a center-of-gravity position at 21.4 percent of the mean aerodynamic chord.

The results of tests of 22 triangular wings, representing two leading-edge shapes for each of 11 apex angles, at Mach numbers 1.62, 1.92, and 1.40 are presented and compared with theory. All wings have a common thickness ratio of 8 percent and a common maximum-thickness point at 18 percent chord. Lift, drag, and pitching moment are given for all wings at each Mach number. The relation of transition in the boundary layer, shocks on the wing surfaces, and characteristics of the pressure distributions is discussed for several wings.

Report is a brief summary of investigations on symmetrical and cambered airfoils in the DVL high-speed tunnel. Some information on the effects of low aspect ratio are also included.

"Available information on gust structure, airplane reactions, and pertinent operating statistics has been examined. This report attempts to coordinate this information with reference to the prediction of gust loads on airplanes. The material covered represents research up to October 1947" (p. 807).

"The aerodynamic forces on an oscillating airfoil or airfoil-aileron combination of three independent degrees of freedom have been determined. The problem resolves itself into the solution of certain definite integrals, which have been identified as Bessel functions of the first and second kind and of zero and first order. The theory, being based on potential flow and the Kutta condition, is fundamentally equivalent to the conventional wing-section theory relating to the steady case" (p. 23).

From Introduction: "Recent developments in the statistical theory of extreme values (references 4 to 10) have indicated a somewhat more rational approach to the problem of predicting the probability of occurrence The present report summarizes some of these findings, indicates the method of application, and evaluates their applicability to certain gust-load problems ."

"On the basis of linearized supersonic-flow theory, generalized equations were derived and calculations made for the lift and damping in roll of a limited series of thin sweptback tapered wings. Results are applicable to wings with streamwise tips and for a range of supersonic speeds for which the wing is wholly contained between the Mach cones springing from the wing apex and from the trailing edge of the root section. A further limitation is that the tip Mach lines may not intersect on the wing" (p. 395).

"A chart in terms of nondimensional parameters is presented for the theoretical critical stress in torsion of simply supported cylinders stiffened by identical equally spaced rings of zero torsional stiffness. The results are obtained by solving the equation of equilibrium by means of the Galerkin method. Comparison of the theoretical results with experimental results indicates that ring-stiffened cylinders buckle, on the average, at a buckling stress about 15 percent below the theoretical buckling stress" (p. 1).

The first partial report, FB 2000, contained a discussion of the derivation of the equations of motion and their solutions for a tab-controlled airplane; the results obtained there are now to be applied to the longitudinal motion of tab-controlled airplanes. In view of the abundance of structural factors and aerodynamic parameters, a general discussion of the problems is unfeasible. Thus it is demonstrated on the basis of examples what stability, oscillation, and stress conditions are to be expected for tab-controlled airplanes. (author).

Measurements are presented at Mach numbers from about 1.3 to 1.5 of reflection characteristics and the relative upstream influence of shock waves impinging on a flat surface with both laminar and turbulent boundary layers. The difference between impulse and step waves is discussed and their interaction with the boundary layer is compared. General considerations on the experimental production of shock waves from wedges and cones and examples of reflection of shock waves from supersonic shear layers are also presented.