Report presenting an approximate method of applying the available data on various types of flaps in the design of fighter brakes together with several examples of its use. The computed effects of flap type, size, location, and deflection as well as the effects of altitude and initial velocities on braking characteristics are also shown in some examples using the method to determine various flap arrangements.

Report presenting force-test measurements in two-dimensional flow in the 4- by 6-foot vertical tunnel of the characteristics of an NACA 0015 airfoil equipped with a plain flap with a chord 30 percent of the airfoil chord and a plain tab with a chord 20 percent of the flap chord. Results regarding lift, hinge moment of flap, pitching moment, drag, and tab characteristics are provided.

From Summary: "Tests have been made to determine the effect of a gap at the flap nose upon the aerodynamic section characteristics of an NACA 0009 airfoil with a plain flap and tab. The results are presented in the form of airfoil and flap section characteristics for several flap deflections, tab deflections, and for four sizes of gap."

Report presenting an investigation in the 7- by 10-foot wind tunnel of an NACA 23012 airfoil with a 30 percent-chord Maxwell leading-edge slat and a slotted and a split flap. The main purpose was to determine the optimum slot cap of the Maxwell slat for, and the aerodynamic section characteristics of, the airfoil with several deflections for both types of flaps. Curves of lift, drag, and pitching-moment characteristics for optimum arrangements are provided.

Report summarizes the available hinge-moment data for unshielded horn-balanced control surfaces. The purpose is to correlate the available data to assist with estimating the balance characteristics for use in the design and alteration of control surfaces with horn balances. Plan forms and variation of incremental hinge-moment-coefficient slopes with balance coefficients are presented.

Report presenting drag measurements in the two-dimensional low-turbulence tunnel of an available 100-inch-chord model of the NACA 23016 wing section. Results regarding the curves of section drag coefficient plotted against Reynolds number for various surface conditions and lift coefficients, variation of drag coefficient with lift coefficient, and effects of skin friction are provided.

Report presenting an investigation of a slot-lip aileron and a plain aileron, singly and in combination, on an NACA 23012 wing with a full-span flap. The characteristics of these lateral-control devices were essentially the same as those of similar devices on the wing with full-span NACA slotted flaps as tested in a previous investigation.

"Formulas for the calculation of hinge-moment characteristics of an elevator with a spring tab have been developed in terms of basic aerodynamic parameters, spring stiffness, and airspeed. The formulas have been used in a study of the stick-force gradients on a pursuit airplane equipped with an elevator with a spring tab. Charts are presented showing the variation of stick-force gradient in accelerated flight over a large range of speed and the complete range of spring stiffness for various center-of-gravity locations, altitudes, and airplane sizes" (p. 1).

Report presenting hinge-moment, lift, pressure difference across the balance, and pressure-distribution measurements in the two-dimensional test section of the stability tunnel on a 0.60 aileron-chord sealed internal-balance aileron on a specified NACA airfoil. The primary test objective was to determine the effect of speed on the action of the aileron.

"Hinge-moment, lift, and pressure-distribution measurements were made in the two-dimensional test section of the NACA stability tunnel on a blunt-nose balance-type aileron on an NACA 66,2-216 airfoil at speeds up to 360 miles per hour corresponding to a Mach number of 0.475. The tests were made primarily to determine the effect of speed on the action of this type of aileron. The balance-nose radii of the aileron were varied from 0 to 0.02 of the airfoil chord and the gap width was varied from 0.0005 to 0.0107 of the airfoil chord. Tests were also made with the gap sealed" (p. 1).

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 a summary of published information on braking friction coefficients. Analysis indicates that the magnitude of the friction coefficient available will affect the technique required for obtaining the shortest ground run only under extreme conditions.

Report presenting an investigation which found that the absolute viscosity of exhaust gases from a gasoline engine was measured at a range of temperatures and compositions. Results regarding preliminary runs, calibration runs at room temperature, check runs at medium temperatures, and exhaust gas measurements are provided.

"Blunt-nose and elliptical-nose overhangs of 0.35 and 0.50 flap chord and a plain overhang on a flap having a chord of 0.20 airfoil chord have been tested in two-dimensional flow on an NACA 0009 airfoil. The results of the tests are presented as aerodynamic section characteristics for several flap deflections with the gap at the flap nose sealed or unsealed. Tests were made also to determine the effectiveness of a tab of 0.20 flap chord on the plain sealed flap and on a sealed flap having an elliptical overhang of 0.35 flap chord" (p. 1).

Report presenting wind-tunnel tests in two-dimensional flow to investigate the aerodynamic characteristics of a double flap with an internal and overhang balance. Three sizes of each type of balance were tested with three relative rates of deflection of the two flaps. Results regarding lift, hinge moment, drag, and pitching moment are provided.

Report presenting an investigation of a full-scale horizontal tail surface to determine the elevator-fabric deflection at high speeds and the aerodynamic effects of the fabric deflection. Two fabric-covered elevators differing only in rib spacing and a solid wooden elevator were tested. Results regarding fabric deflection and aerodynamic characteristics are provided.

Report presenting results of a full-scale horizontal tail surface made to determine the effect of elevator-profile modifications and trailing-edge strips on the elevator hinge-moment characteristics for elevators having fixed plan plan form and constant balance. Results regarding the basic data with the metal elevator, effect of trailing-edge angle, effect of nose shape, and effects of trailing-edge strips are provided.

Report discusses the results of force testing of the aerodynamic characteristics of an NACA 0009 airfoil with a double plain flap; it consisted of a plain forward flap with a chord 20 percent of the airfoil chord and a plan rearward flap with a chord 15 percent of the airfoil chord. Comparisons were made to the characteristics of a 0.50c single plain flap. The lift, hinge moments, drag, and pitching moments are described.

Report presenting a series of tests of the Brewster XSBA-1 airplane conducted to determine the effect of various tail modifications. The current report describes an investigation of flying qualities of the airplanes with its original tail surfaces. Testing regarding longitudinal stability and control and stalling characteristics are provided.

Report presenting flight tests of an all-movable vertical tail of reduced area of the Fairchild XR2K-1 airplane. Results are in agreement with previously obtained data on a larger all-movable tail. Results regarding rudder effectiveness, directional stability, rudder-free lateral motion, rudder hinge moments, and areas of future research are provided.

"Recent developments in airfoil-testing methods and fundamental air-flow investigations, as applied to airfoils, are discussed. Preliminary test results, obtained under conditions relatively free from stream turbulence and other disturbances, are presented. Suitable airfoils and airfoil-design principles were developed to take advantage of the unusually extensive laminar boundary layers that may be maintained under the improved testing conditions" (p. 1).

Report presenting values of the lateral-stability derivative, the rate of change of yawing-moment coefficient with yawing angular velocity, contributed by the wing, the fuselage, and the vertical tail, which have been determined for a midwing airplane model by the free-oscillation method.

Report presenting the determination of the effects of static margin and rotational damping in pitch on the longitudinal stability characteristics of an airplane by flight tests of a model in the NACA free-flight tunnel. The rotational damping in pitch was varied over a wide range by using horizontal tails that varied in area from 0 to 24 percent of the wing area. Results regarding the effect of variation of static margin and effect of variation of rotational damping are provided.

"The gross weight, beam, and afterbody length of 12 contemporary flying boats and amphibians with pointed afterbodies are tabulated and correlated. For most of the hulls considered, the afterbody length-beam ratios are shown to be directly proportion to the gross-load coefficients" (p. 1).