Report presenting wind-tunnel testing in two-dimensional flow to investigate the aerodynamic characteristics of a flap balanced by a large overhang linked to deflect more slowly than the flap. Three lengths of blunt-nose overhang were tested linked to a 0.30-airfoil-chord straight-contour flap on an NACA 66-009 airfoil. Results regarding lift, hinge moment, drag, pitching moment, and practical considerations are provided.

Report presenting an investigation in the two-dimensional low-turbulence pressure tunnel of three different types of NACA airfoil sections equipped with split flaps with chords 20 percent of the airfoil chord. The main purpose was to determine the maximum-lift characteristics of these low-drag airfoil sections with split flaps.

Report discussing an investigation of the aerodynamic effects of horn balances with various plan forms and of guards on a horizontal tail surface. Rounding the adjacent horn and stabilizer edges causes negligible changes to aerodynamic effects except for the area moment of the horn. A solid horn guard mounted on the end of the stabilizer was found to increase the rate of change of lift with angle of attack and elevator deflection.

Results of subject tests indicate the difficulty of obtaining closely balanced rudder surfaces for most tail assemblies with shielded horns and maintaining a near zero rate-of-change of hinge-moment coefficient without an additional balancing device. A comparison is made between shielded and unshielded horn test results. Pressure distribution and tuft tests of flow over different shaped horns showed higher critical speed for medium-taper nosed horn. The trim tab nose shape had little effect on tab test results.

The effects of jet-motor operation on the stability and control characteristics of two fighter-type airplanes as determined by wind-tunnel tests of 1/5-scale models are presented. It is shown that the action of the jets is to cause a small loss in stick-fixed stability which is predictable from known theories.

An investigation has been made to determine the effect of control-surface profile modifications on the aerodynamic characteristics of an NACA low-drag airfoil equipped with a 0.20-chord and a 0.15-chord aileron. Tab characteristics have been obtained for 0.20-aileron chord tabs on two of the 0.20-chord ailerons. Basic data are presented from which the effect of tabs can be calculated for specific cases. The data are sufficient for the solution of problems of fixed tabs with a differential linkage, as well as simple and spring-linked balancing tabs.

Tests were conducted at dynamic pressure of 50 lb per square foot with lift drag and pitch moment measurements throughout useful angle of attack range for constant flap deflection and position of a low-drag airfoil. Two slots were investigated and practical flap paths were selected for each Slot shape had a negligible effect on the maximum lift coefficient flap deflected, the rounded-entry slot had lower profile drag.

"This report outlines the flight conditions that are usually critical in determining the design of components of an airplane which affect its stability and control characteristics. The wind-tunnel tests necessary to determine the pertinent data for these conditions are indicated, and the methods of computation used to translate these data into characteristics which define the flying qualities of the airplane are illustrated" (p. 1).

This report outlines the flight conditions that are usually critical in determining the design of components of an airplane which affect its stability and control characteristics. The wind-tunnel tests necessary to determine the pertinent data for these conditions are indicated, and the methods of computation used to translate these data into characteristics which define the flying qualities of the airplane are illustrated.

This report outlines the flight conditions that are usually critical in determining the design of components of an airplane which affect its stability and control characteristics. The wind-tunnel tests necessary to determine the pertinent data for these conditions are indicated, and the methods of computation used to translate these data into characteristics which define the flying qualities of the airplane are illustrated.

Report presenting the results of aerodynamic tests of seven-blade propellers which were considered as a possible arrangement to avoid vibration difficulties. Variations of relative blade angle and rotational speeds of the front and rear components of a six-blade dual-rotating propeller were also investigated.

Report presenting testing in the stability tunnel of two types of spring tab used as balances on a partial-span plain aileron. The tabs were connected to a spring located in the control system so that tab deflection was dependent on the control force.

Report presenting a series of wind-tunnel tests made in the 7- by 10-foot tunnel of the Curtiss XBTC-2 model with power. The object of the tests was to determine and to improve, as necessary, the complete aerodynamic characteristics of the model. The report includes the results of the longitudinal stability investigation of the original model along with results from tests of various modifications.

Report presenting testing of a model of the Curtiss XBTC-2 airplane in the 7- by 10-foot tunnel. This report consists of a preliminary investigation of the lateral stability and control of one particular configuration of the airplane. Results regarding the effect of wing plan form and power at small and large angles of yaw, the effect of upturned wing tips, outboard flap modification, canopy opening, aileron control, and rudder-free characteristics are provided.

Report discusses measurements of gust size and intensity during the spring and summer of 1941 and 1942 under a variety of weather conditions and various altitudes up to 34,000 feet. Information about average gust-gradient distance, gust velocities, and gust frequency is included.