Report presenting an application of the principle of aileron-stick forces and mechanical advantage to an aileron installation in which the stick forces are small over the low-deflection range and excessively large at full deflection.

"The data are presented in coefficient form and include lift, drag, and pitching-moment coefficients of the airfoil-flap comoinations and the normal-force, chord-force, and hinge-moment coefficients of the upper (perforated split) flap and lower (slotted) flap" (p. 1).

Report presenting testing in the two-dimensional turbulence tunnel of a model of the tip section of the wing of the XP-63 airplane. Several alterations of the skirts and balance on the internal-balance aileron were tested to obtain various aerodynamic characteristics of the aileron.

From General Analysis: "The purpose of part I of this paper is to show how the loading that gives the minimum induced energy loss can be obtained from rather elementary considerations and to present design charts from which such a plan form can be quickly obtained for any set of design conditions."

Report presenting aerodynamic tests of a 300-pound M-31 demolition bomb. Force tests at a range of angles of attack were made at Mach number 0.725, which corresponds to a speed of 810 feet per second at sea level. Results regard the drag, lift, and pitching moment are provided.

Report presenting aerodynamic testing of scale models of the Edo seaplane floats for the SB2U-3, OS2U-2, and XSB2C-2 seaplanes. Various coefficients, pitching moment, yawing moment, and drag coefficients are provided.

Report presenting an analysis of the effects of heat and compressibility in the flow through the internal systems of aircraft. Equations and charts are developed whereby the flow characteristics at key stations in a typical internal system may be readily obtained.

From Introduction: "The purpose of this paper is to show, in a similar manner, the effect of change in the core structure of the tubular intercooler on the over-all dimensions when the operating conditions are fixed."

Analysis was made to determine characteristics required of a balancing-tab system for ailerons in order to reduce aileron stick forces to any desired magnitude. Series of calculations based on section data were made to determine balancing-tab systems of various chord tabs and ailerons that will give, for a particular airplane, zero rate of aileron hinge moment with aileron deflection and yet will produce same maximum rate of roll as a plain unbalanced 15-percent chord aileron of same span. Effects of rolling velocity and of forces in tab link on aileron hinge moments have been included.

Report presenting an analytical study of the influence of full-span slotted and Fowler flaps on the requirements for horizontal tail surfaces. The elevator deflection required to land at three-point attitude, elevator deflection required to stall the airplane at altitude, and permissible center-of-gravity range have been calculated for a fighter-type airplane.

Report presenting tail-surface characteristics calculated from wind-tunnel data, which have been reported to not correspond with flight-test measurements. The primary problem under consideration is the calculation of the effect of tab deflection on the free-floating angle of the elevator, as in a servocontrol.

"Three Franz-type temperature probes and a pitot-static tube for use in supercharger passages have been calibrated in the NACA 24-inch high-speed wind tunnel. These instruments were designed for use in supercharger investigations" (p. 1).

Report presenting the calibrations of three types of service pitot-static tubes over an approximate range of speeds of 150 to 600 miles per hour. The calibrations indicated a need for a pitot-static tube with greater accuracy, especially at higher speeds. Results regarding the service tubes, Prandtl tube, Eigh-speed tube, and a comparison of the tubes are provided.

Report presenting lift and elevator hinge-moment characteristics were measured on horizontal tail provided with elevators having three different beveled trailing edges. Results regarding fuselage alone and fuselage interference, lift characteristics of fuselage-tail combination, elevator hinge-moment characteristics, drag, and comparison with data from two-dimensional-flow tests are provided.

Report presenting lift and elevator hinge-moment characteristics of a horizontal tail with various plain and balanced elevators and mounted on a typical pursuit fuselage as measured in the 7- by 10-foot wind tunnel at attitudes simulating normal-flight and spin conditions. The lift effectiveness of the elevator was practically independent of the size of the aerodynamic balance. Results regarding the fuselage alone and fuselage interference, lift characteristics of fuselage-tail combinations, lift effectiveness of the tab, elevator hinge moments, parameters, effect of yaw on elevator hinge moments, effect of tab on elevator hinge moments, drag, and comparison with two-dimensional data are provided.

Two airfoil plans were used for propeller blades. One is modified Clark Y section designed for structural reliability and the second an NACA 16 airfoil section designed to produce minimum aerodynamic losses. At low air speeds, the propeller designed for aerodynamic effects showed a gain of from 1.5 to 4.0 percent in propulsive efficiency over the conventional type depending on the pitch. Because of the numerous variables involved, the effect of each one on the aerodynamic characteristics of the propellers could not be isolated.

Report presenting a method of comparing the performance, weight, and general dimensional characteristics of intercoolers. The performance and dimensional characteristics covered in the comparisons include cooling effectiveness, pressure drops and weight flows of the charge and cooling air, power losses, volume, frontal area, and width.

Report presenting an investigation to determine whether the use of a 78 degree countersinking tool instead of a 82 degree countersinking tool for riveting would substantially alter the conclusion reached in a previous paper regarding the placement of rivets for maximum strength.

Report presenting a brief, nontechnical discussion of condensation trails for flying personnel. World maps showing trail-forming zones at different altitudes and seasons are presented. Means for suppression trails are given.

"This report describes the material, cutting-tool development, and machining procedure used in constructing an air-cooled cylinder barrel having a cooling muff with 2-inch fins spaced 1/8 inch. Details of two types of thread form used for the barrel to head assembly with the cooling muff are also presented" (p. 1).

Report presenting a control-motion study in flight that is part of series covering a range of types and sizes of modern airplanes. This particular one involves the PBM-3 flying boat, which is equipped with a control mechanism typical of the cable-type systems in large transport, cargo, or bomber airplanes as well as those employed in flying boats. The elasticity of the elevator control system of the PBM-3 was such to limit the obtainable acceleration to about 3g for center-of-gravity positions in the usual operating range; that is, 26 to 30 percent mean aerodynamic chord, and for the range of airspeeds covered by the tests.

Report presenting testing of a Pratt & Whitney R-1830-43 engine mounted in a B-24D nacelle in the full-scale wind tunnel in order to investigation the potential improvements of fuel economy. Suggestions for improving the cruising power and cruising range by operating at specified fuel-air ratios are provided.

Report presenting an investigation conducted in the full-scale tunnel to determine methods of improving the cooling of the B-24D engine installation. The B-24D is a four-engine high-wing monoplane having a span of 110 feet, a wing area of 1048 square feet, and a gross weight of 56,000 pounds.

Report presenting the results of comparative cooling tests run on two Wright C9GC (G-200) cylinders, one with the original steel fins and one with 1-inch spiral copper fins brazed on the barrel. Calculations were also performed using copper and aluminum fins with the same weight as the original steel fins, which showed positive results. Results regarding cylinder-temperature correlation, piston-temperature correlation, and comparative performance are also provided.