"At the request of the Bureau of Aeronautics, Navy Department, tests were made in the variable-density wind tunnel of a tapered wing of 3-10-18 plan form and based on the NACA 4400R series sections. The wing was also tested with 0.2 chord split flaps, deflected 60 degrees, in the center of the wing and having flat span to wing span ratios of 0.3, 0.5, 0.7, and 1.0, respectively" (p. 1).

Report presenting an analysis of available data on vee-tail surfaces. The analysis indicated that a vee tail designed to provide values of stability and control parameters equal to those provided by a conventional tail would probably provide no reduction in area unless the conventional vertical tail is in a bad canopy wake or unless the vee tail has a higher effective aspect ratio than the conventional vertical and horizontal tails.

"Test data of balanced ailerons have been collected from NACA and British sources. These data, which are presented in the form of charts, are grouped as A - ailerons with Frise balances, B - ailerons with blunt-nose balances, C - ailerons with internal balances, D - ailerons with contour modifications, and E - ailerons with tabs. Results of flight tests and of wind-tunnel tests in both two- and three-dimensional flow are presented but no correlation nor resume of the data has been included" (p. 1).

Report presenting an investigation in the 7- by 10-foot tunnel of various modifications of the trailing-edge portion of a 0.20-chord plain aileron on a partial-span model of a tapered low-drag wing. The modifications tested included various amounts of symmetrical and unsymmetrical thickening and beveling of the aileron trailing edge. Results regarding coefficients and corrections, characteristics with ailerons neutral, characteristics with ailerons deflected, aileron trim characteristics, and estimated aileron-control characteristics are provided.

Report presenting testing to determine the aerodynamic characteristics of an NACA 66-series 16-percent-thick low-drag tapered wing with Fowler and split flaps. The wing had a straight trialing edge and a constant-chord center section. Results regarding lift and pitching-moment characteristics and stalling characteristics are provided.

"An investigation has been conducted in the Langley rectangular high-speed tunnel to determine the effect of compressibility on the pressure distribution for a modified NACA 65,3-019 airfoil having a 0.20-chord flap. The investigation was made for an angle-of-attack range extending from -2 to 12 deg at .20 flap deflections from 0 to -12 deg. Test data were obtained for Mach numbers from 0.28 to approximately 0.74" (p. 1).

Report presenting equations relating the various dimensions, air mass flow, and performance of a cross-flow tubular intercooler in which the charge flows across and the cooling air through the tubes. Design charts are presented from which the intercooler design characteristics and performance can be quickly determined.

Report presenting an investigation of the effects on stability and control of a pusher propeller behind conventional horizontal and vertical tail surfaces in the free-flight tunnel by tests of a scale model of a submerged-engine pusher airplane. The investigation consisted of flight and balance tests at windmilling and high-power conditions with a partial-span Zap extensible flap extended and retracted. Results regarding the longitudinal stability, longitudinal control, stalling characteristics, lateral stability, and lateral control are provided.

Report presenting determinations of boundary-layer transition on the NACA 0012 and 23012 airfoils in the high-speed wind tunnel over a range of Reynolds numbers. For all of the lift coefficients that testing occurred at, transition occurred in the region of estimated laminar separation at low Reynolds numbers and approached the point of minimum static pressure as a forward limit at high Reynolds numbers.

Report presenting an extension of previously reported data on the variation of maximum lift coefficient with Mach number, camber, and thickness ratio. The data were obtained from pressure-distribution tests in the 8-foot high-speed tunnel of six propeller airfoils of 1-foot chord.

Report presenting an investigation in the 7- by 10-foot wind tunnel of the effects of various modifications to the profile of a 0.20-chord plain sealed aileron and a 0.15-chord plain sealed aileron on an NACA 66,2-216 airfoil. Thickening of the aileron was found to reduce the aileron effectiveness, reduce the slope of the wing section lift curve, and reduce the hinge-moment coefficients. Results regarding the section data, aileron effectiveness, aileron hinge moments, lift, pitching moment, drag, and Reynolds number are provided.

Report presenting data obtained from tests of models and airplanes relating to the effects of various wing armament installations, which have been collected and analyzed. Three types of gun installations were considered: gun ports, protruding machine guns, and cannon. The ways that each type of installation affected the lift and drag characteristics are provided.

Report presenting an investigation in the 7- by 10-foot wind tunnel of the effects of modifications to the trailing edge of a 0.20-chord plain sealed aileron on an NACA 66,2-216 airfoil. The modifications considered consisted of various amounts of symmetrical thickening and beveling of the aileron trailing edge. Results regarding aileron effectiveness, aileron hinge moments, aileron control forces, lift, pitching moment, drag, and Reynolds number are provided.

Report presenting an analysis to determine the effect on propeller performance of extension flaps added to the trailing edge of a propeller blade. A method is included to determine the angle that the flap extension must make with the chord in order to obtain a particular load distribution.

The development of the laminar boundary layer in a compressible fluid is considered. Formulas are given for determining the boundary-layer thickness and the ratio of the boundary-layer Reynolds number to the body Reynolds number for airfoils and bodies of revolution. It is shown that the effect of compressibility will profoundly alter the Reynolds number corresponding to the upper limit of the range of the low-drag coefficients.

"A mathematical analysis of radiator design has been made. The volume of the radiator using least total power has been expressed in a single formula which shows that the optimum radiator volume is independent of the shape of the radiator and which makes possible the construction of design tables that give the optimum radiator volume per 100-horsepower heat dissipation as a function of the speed, of the altitude, and of one parameter involving characteristics of the airplane. Although, for a given set of conditions, the radiator volume using the least total power is fixed, the frontal area, or the length of the radiator needs to be separately specified in order to satisfy certain other requirement such as the ability to cool with the pressure drop available while the airplane is climbing" (p. 1).

Report presenting a comparison of the cooling-test data obtained on the identical Wright R-3350-14 engine equipped with the same cooling pressure-tube installation. The comparison reveals the large difference in cooling pressure drop that may be obtained in different test installations with the identical engine and pressure-tube installation because of an injudicious choice of pressure-tube locations.