Memorandum presenting an investigation of three models of a delta-wing airplane designed for a long-range subsonic cruise and a supersonic dash. Results regarding the aerodynamic characteristics of the models and effect of elevon deflection on aerodynamic characteristics of the four-engine model are provided.

Memorandum presenting three types of aerodynamic interference originating from forward components of airplanes, which are shown to contribute to decreased vertical-tail effectiveness. The vorticity originating from a slender fuselage ahead of the wing resulted in a marked reduction in vertical-tail effectiveness with angle of attack for one model.

Memorandum presenting an investigation in the blowdown tunnel of the pressure tunnel to determine the aerodynamic characteristics of a sting-mounted Douglas Aircraft Company store in the presence of, but not attached to, an unswept semispan cantilevered wing of aspect ratio 4.0. The influence of the store on the aerodynamic characteristics of the wing was also obtained.

Report presenting the damping-in-roll coefficients for a series of thin triangular plan-form wings and two rectangular wings in the 9-inch supersonic wind tunnel. The damping in roll of the rectangular wings was very close to what was predicted by linear theory, but the triangular wings gave results approximately 10 percent below that predicted when the wing leading edges were well ahead of or behind the Mach cone.

From Introduction: "In the analysis given herein, which was made at the NACA Lewis laboratory, the expression for eddy diffusivity given in reference 1 is modified in order to account for the effect of kinematic viscosity in reducing the turbulence in the region close to the wall. The effects of variable viscosity and of length-to-diameter ratio are also investigated."

Tests of a powered dynamic model of the Columbia XJL-1 amphibian were made in Langley tank no.1 to determine the hydrodynamic stability and spray characteristics of the basic hull and to investigate the effects of modifications on these characteristics. Modifications to the forebody chime flare, the step, and the afterbody, and an increase in the angle of incidence of the wing were included in the test program. The seaworthiness and spray characteristics were studied from simulated taxi runs in smooth and rough water. The trim limits of stability, the range of stable positions of the enter of gravity for take-off, and the landing stability were determined in smooth water. The aerodynamic lift, pitching moment, and thrust were determined at speeds up to take-off speed.

From Summary: "The heat losses from the envelope surface of a U.S. Navy K-type airship are evaluated to determine if the use of heat is a feasible means of preventing ice and snow accumulations on lighter-than-air craft during flight and when moored uncovered. Consideration is given to heat losses in clear air (no liquid water present in the atmosphere) and in probable conditions of icing and snow. The results of the analysis indicate that the amount of heat required in flight to raise the surface temperature of the entire envelope to the extent considered adequate for ice protection, based on experience with tests of heavier-than-air craft, is very large."

Report presenting three types of aerodynamic interference originating from forward components of airplanes, which are shown to contribute to decreased vertical-tail effectiveness.

Report presenting an investigation to determine the aerodynamic characteristics of a sting-mounted Douglas Aircraft Company store in the presence of an unswept semispan cantilevered wing of aspect ratio 4.0. Results regarding wing loads and store loads are provided.

The forced-convection heat-transfer characteristics of sodium hydroxide were experimentally investigated. The heat-transfer data for heating fall slightly above the McAdams correlation line, and the heat-transfer data for cooling are fairly well represented by the McAdams correlation line.

Memorandum reporting the tensile and crazing properties for five cast polymethy lmethacrylate sheets in which the molecular weight of the resin was 90,000, 120,000, 200,000, 490,000, and 3,160,000. Both stress crazing and stress-solvent crazing tests were conducted. Results regarding the standard tensile tests, stress-solvent crazing tests, and discussion of failure and crazing are provided.

Report discussing testing of a Douglas D-558-II to investigate its longitudinal stability characteristics in accelerated flight at supersonic speeds. Information about the normal-force coefficients and their relation to stability and pitch-up of the aircraft is included.

Report presenting an investigation of the flight characteristics of the Bell X-5 research airplane with sweepback that can be varied from 20 degrees to 59 degrees in flight. Lift and drag data have been obtained for the 59 degree sweep configuration for a range of Mach numbers and from zero to almost maximum lift.

Report presenting the rolling effectiveness of 0.2-chord, trailing-edge ailerons on high-aspect-ratio sweptback wings over a range of Mach numbers. Some effects of spanwise aileron location on rolling effectiveness were measured by testing ailerons on the inboard half, the outboard half, and the full length of the exposed wings.

Report presenting an investigation in the 7- by 10-foot tunnel to determine the rolling stability derivatives of a complete model and its components over a range of Mach numbers and angles of attack. Positive damping in roll was indicated for the model throughout the tested ranges, but significant losses in damping occurred in going from moderate to high angles of attack. Results regarding the experimental derivatives of damping in roll, yawing moment, lateral force due to rolling, and some estimated derivatives, including wing fuselage, tail contribution, and complete model are provided.

Report presenting an investigation of an axial-flow compressor rotor with a 13-percent reduction in exit annulus in Freon-12 gas at a range of tip speeds. In order to analyze the results caused by the reduction, the performance of the rotor was compared to that of the same rotor with a constant annular area. Results regarding the overall performance, radial variation of performance, and blade-element performance are also provided.

Report presenting the results of an investigation of the static longitudinal stability and control characteristics of a canard airplane configuration without analysis for a range of Mach numbers. The configuration had an unswept wing, an unswept canard, a low aspect ratio vertical tail, and a Sears-Haack body. Data are presented for various combinations of the canard, wing, and vertical tail for a range of angles of attack and canard deflection angles.

Report presenting the results of an investigation of the static longitudinal stability and control characteristics of a canard airplane configuration without analysis for a range of Mach numbers from 0.70 to 2.22. The configuration consisted of a triangular wing, an unswept canard, a low aspect ratio vertical tail, and a Sears-Haack body. Data are presented for various combinations of the canard, wing, and vertical tail for a range of angles of attack and canard deflection angles.