Report presenting flight measurements made on a modern pursuit airplane to determine the approximate magnitude of the horizontal tail loads in accelerated flight. Pressures at a few points were used as an index of the tail loads by correlating these pressures with complete pressure-distribution data obtained in the NACA full-scale tunnel.

From Summary: "A general representation of fan and turbine arrangements on a single classification chart is presented which is made possible by a particular definition of the stage of an axial-flow fan or turbine. Several unconventional fan and turbine arrangements are indicated and the applications of these arrangements are discussed."

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 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.

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 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 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 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).

Report presenting vibration tests of a four-blade single-rotating propeller operating in a simulated pusher condition performed because the combination of wake and downwash behind a wing might provide serious excitation for reactionless vibrations of propellers with four or more blades. Measurements of propeller vibratory stress were made for various airspeeds, engine speeds, and engine powers.

Report describes a procedure for instrumenting, testing, and presenting the overall characteristics of any engine turbosupercharger installation. The preflight analysis of the system, required testing, importance of accurate data recording, measurements to record, methods of measuring, and presentation of results are also included.

Report presenting an investigation to determine the effect of varying the carburetor throttle settings on the flow characteristics at the outlet of the supercharger inlet elbow. Air flow tests were made at several carburetor throttle settings ranging from open to closed. Results regarding distortion and turbulence are provided.

Report presenting a concept of a simplified vortex system of a rotor wake in order to obtain a formula for the normal component of induced velocity along the fore-and-aft diameter of the rotor disk of a helicopter rotors.

Report presenting a scale powered model of the Douglas XSB2D-1 airplane tested with a four-blade dual-rotation propeller and a four-blade single-rotation propeller. To make the results more directly comparable, no other changes were made to the model. Results regarding longitudinal stability, directional characteristics, and lateral stability are provided.

Report presenting an investigation to determine the effects of wing loading and altitude on lateral stability and control in the free-flight tunnel. The results of flight tests of the model were correlated with calculated stability boundaries, and an effort was made to determine for each loading condition the airplane configuration that gave the best flight characteristics. Results regarding the lateral stability, lateral control, and general flight behavior are provided.

Report discussing testing to determine the effect of a horizontal tail on the lateral-stability characteristics of a high-wing, a midwing, and a low-wing monoplane. The model was created from a circular fuselage, an NACA 23012 tapered wing, and an NACA 0009 horizontal tail surface. Information about the effective aspect ratio of the tail, restoring moment of yaw, and vertical-tail effectiveness as compared to the wing position is provided.

From Introduction: "The present paper covers step 1 of the outlined investigation, includes methods of computing the variation of wing and tail loads, and gives numerical results of the application of the theory to the BT-9B airplane. Finally, theoretical formulas are developed and charts are given for computing the maximum increments of wing load, the down-tail load, and the up-tail load following a given elevator displacement."

Report discusses graphs of constants meant to be used with a knowledge of maximum total head loss, static-pressure decrement, and integral of total-head loss across the wake of an airfoil to determine the section profile-drag coefficient. Computations of free-stream Mach numbers for certain assumed types of total-pressure distribution in the wake are provided to compare theoretical drag coefficients as determined by other equations based on the momentum method. While some disagreements are found, the more rapid technique is usable for wide variations in wake shapes for a Mach number range of 0.5 to 1.0.

Report presenting porpoising tests of three rudimentary models composed of two V-bottom planing surfaces in tandem and fitted with a tail plane. The upper and lower branches of the upper trim limit of stability were determined for three angles of dead rise and two depths of step.