Report presenting an investigation to study the use of various high-lift devices on the horizontal tail of a canard airplane model as a means of increasing the allowable center-of-gravity travel. The results indicated that the large increases in allowable center-of-gravity travel could be obtained using the devices. Results regarding the basic aerodynamic data, effect of tail configuration on the allowable center-of-gravity travel, and a comparison of measured and predicted values of the allowable center-of-gravity travel are provided.

Report discussing an investigation into several types and sizes of flaps and spoilers located forward of the elevators on the upper surface of the horizontal stabilizer of a model of a radial-engine pursuit airplane. Information about the elevator characteristics, elevator-fixed and elevator-free balance lift coefficient, and trim drag coefficient for a range of Mach numbers is provided.

Memorandum presenting an investigation in the supersonic pressure tunnel at a free-stream Mach number of 2.01 and at angles of attack up to 15 degrees of the static pressures and boundary-layer characteristics on the forward parts of nine fusleages of various cross-sectional shapes. Results regarding the static pressure distributions, boundary-layer characteristics, and selection of fuselage shapes for use with top-mounted scoop inlets are provided.

Report presenting testing of the performance of a twin-duct air-intake system mounted on the sides of a 1/8-scale fuselage forebody model of a proposed aircraft at several Mach numbers, angles of attack, and yaw. Results regarding the inlet survey, compression-surface boundary-layer removal and effects of second-ramp position, instability, effect of cant on inlet performance, inlet performance with 0 and 30 degree second ramp angles, performance with fixed second-ramp angles, and effect of canards are provided.

Report presenting tests at Mach numbers between 1.36 and 2.01 of a twin-scoop air intake enclosing 61.5 percent of the maximum circumference of a body of revolution and located five forebody diameters behind the apex, which showed that the total pressure recovered after diffusion was about 10 percent greater than that attained in previous tests with an annular entrance of the same area.

Report presenting the results of tests on a model of a jet-propelled airplane and a comparison of drag, maximum lift coefficient, and elevator angle required for level flight in the wind tunnel and in flight. Results regarding the aerodynamic characteristics, longitudinal control, wing pressure distribution, and dive-recovery flaps are provided.

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 an investigation to determine the effect of leading-edge chord-extensions on high-lift pitching moment and performance characteristics at subsonic and transonic speeds. Three models with the same wings were used. Results regarding low-speed development and high-speed characteristics are provided.

Report presenting measurements of the local total pressures and flow-deflection angles in the flow field of a body and a canard-type control-surface combination at a rearward fuselage station which corresponded to a possible engine inlet location. The survey showed large total-pressure losses in the wake of the control surface and a shift in the circumferential distribution of the boundary-layer air about the fuselage due to deflection of the control surface.

Report presenting approximate methods of analysis applied to the estimation of the normal force and pitching moment of the body and the wing-body and tail-body combinations of an air-to-air missile and to the estimation of the same characteristics of the the complete configuration. Results regarding the isolated body, wing-body combination, tail-body combination, and the complete configuration are provided.

Report presenting an experimental investigation of the effects of a horizontal tail in various vertical positions on the longitudinal stability characteristics of a wing-fuselage combination of 45 degrees sweepback and aspect ratio 8 in the 19-foot pressure tunnel. Testing occurred at two wing incidence angles and various high-lift and stall-control devices at a specified Mach and Reynolds number. The horizontal tail was tested at four vertical positions.

Report presenting aerodynamic characteristics in steady roll on a complete model and its component parts. The model consisted of a wing and horizontal tail with a 45 degree sweepback at the quarter-chord line, a taper ratio of 0.6, an aspect ratio of 4, and NACA 65A006 airfoil sections parallel to the plane of symmetry. Results regarding rolling moment due to rolling, yawing moment due to rolling, and lateral force due to rolling are provided.

The free turbulent mixing of a supersonic jet of Mach number 1.6 has been experimentally investigated. An interferometer, of which a description is given, was used for the investigation. Density and velocity distributions through the mixing zone have been obtained. It was found that there was similarity in distribution at the cross sections investigated and that, in the subsonic portion of the mixing zone, the velocity distribution fitted the theoretical distribution for incompressible flow. It was found that the rates of spread of the mixing zone both into the jet and into the ambient air were less than those of subsonic jets.

Report presenting flight testing of a scale rocket-propelled model of the Convair XF2Y-1 airplane with open ducts and elevons deflected upward 3.5 degrees through a range of Mach numbers. Report presenting lift and stability, drag, and duct flow are provided.

Report presenting an investigation to determine the effects of altitude and inlet-pressure distortions on the steady-state and surge characteristics of the J57-P-1 two-spool turbojet engine in the altitude wind tunnel. Steady-state performance and surge fuel flows were obtained with a uniform inlet distribution at a range of altitudes at flight Mach number 0.8.

"Measurement of the jet thrust of a turbojet engine in flight becomes more difficult as the number and complexity of the engine components increase. It is desirable, therefore, that a general correlation of jet thrust be developed which is applicable to a simple direct reading thrustmeter. In view of this need a correlation is presented which is independent of flight conditions and applicable to both non-afterburning and afterburning engines equipped with nonejector type fixed- and variable-area convergent exhaust nozzles" (p. 1)

From Summary: "Section characteristics for use in wing design are presented for the NACA 23012 airfoil with plain and split flaps of 20 percent wing chord at a value of the effective Reynolds number of about 8,000,000. The flap deflections covered a range from 60 degrees upward to 75 degrees downward for the plain flap and from neutral to 90 degrees downward for the split flap. The split flap was aerodynamically superior to the plain flap in producing high maximum lift coefficients and in having lower profile-drag coefficients at high lift coefficients."

Report presenting testing of a twin-duct air-intake system mounted on the sides of a fuselage forebody model at free stream Mach numbers of 1.5 and 2.0 over angles of attack and yaw. Results regarding the inlet survey, compression-surface boundary-layer removal and effects of second-ramp position, instability, effect of cant on inlet performance, inlet performance with 0 degree and 30 degree second-ramp angles, performance with fixed second-ramp angles, and effect of canards are provided.

The gust and draft velocities from records of NACA instruments installed in P-61C airplanes participating in thunderstorm flights at Clinton County Army Air Field, Ohio, from June 11, 1947 to July 11, 1947 are presented.

"The performance of a 2.8 KS 8100 Cajun solid-propellant rocket motor has been determined from the free-flight test of a single-stage model which reached a velocity of 5,268 feet per second (Mach number, 4.74). Thrust data from the flight test are compared with data obtained from a ground firing test made by the manufacturer and the two are shown to be in agreement." Report presenting general drag, data, and acceleration are also provided.

"The flexural vibration of a rotating propeller blade with clamped shank is analyzed with the object of presenting, in matrix form, equations for the elastic bending moments in forced vibration resulting from aerodynamic forces applied at a fixed multiple of rotational speed. Matrix equations are also derived which define the critical speeds end mode shapes for any excitation order and the relation between critical speed and blade angle. Reference is given to standard works on the numerical solution of matrix equations of the forms derived" (p. 1).

A modified corrugated-insert blade with integrally cast shell and base was developed. This blade was as light as a conventional fabricated corrugated-insert blade. Of four test blades operated in a full-scale turbojet engine, one failed after about 15 hours operation at an inlet gas temperature of 1670 degrees F, a coolant-flow ratio of 0.0064, and a 1/3-span centrifugal stress of approximately 28,000 psi. Three other test blades ran for approximately 16, 31, and 36 hours without failure at similar conditions.

Report presenting the basic performance characteristics of several types of designs of subsonic-diffuser-bypass-duct combinations for bypass flows up to one-third of the total flow. The tested bypass-duct design procedure was found to be greatly oversimplified and was unable to produce satisfactory performance because of the extreme adverse pressure gradient.