"Air-consumption data from calibrations of two radial aircraft engines were analyzed to show the relation of engine air consumption to its primary influencing factors: intake-manifold pressure, exhaust back pressure, intake-manifold temperature, and engine speed. The analysis of the test data from these two engines led to the establishment of a relation of variables upon which the design of automatic metering controls can be based. The data obtained from one engine indicate that the air-consumption correlation obtained for this engine is accurate within 2 percent except under certain conditions that are well outside current engine-operation limits" (p. 1).

Report presenting testing to determine the effect of xylidines on the load-carrying capacity of aircraft-engine oil in several test devices. Lubricating oil and lubricating oil with xylidines added was tested in four different testing machines. In all of the experiments, adding the xylidines made the oil a poorer lubricant in the boundary region of lubrication, where metal-to-metal contact occurs.

Report discussing an investigation to determine the effect of omitting some of the fuel constituents in AN-F-28 Amendment 2 fuel that are normally lost in flight on fuel-vapor loss. Removing the components was found to decrease the fuel-vapor loss and increase the critical altitudes.

Report presenting an investigation by lifting-surface theory of a thin elliptic wing of aspect ratio 6 in a steady roll by means of the electromagnetic-analogy method. The results obtained by lifting-surface theory indicate that the damping in roll for a wing of aspect ratio of 6 is 13 percent less than that give by lifting-line theory and 5 percent less than that given by lifting-line theory with the edge-velocity correction derived by Robert T. Jones applied. Simple practical methods of applying the results of the investigation to wings of other plan forms are given.

Report presenting methods for determining the jet-boundary corrections to the downwash behind models in rectangular wind tunnels. The methods take into account the tunnel dimensions, the type of jet, the span loading of the model, the geometric position of the wind and of the tail in the tunnel, the displacement of the wing wake, and the effect of the slipstream.

Report presenting air-flow surveys made in the region of the tail plane of a typical twin-engine tractor monoplane model with tail surfaces removed. The surveys were made with propellers removed and operating and for both cases included the conditions for flaps retracted and flaps deflected 50 degrees.

Report presenting charts relating helicopter aerodynamic design variables to performance in steady powered flight. The flight conditions covered are hovering, climb, and horizontal flight. The use of the charts is illustrated by numerical examples in order that computations can be made for particular problems.

Report presenting a report illustrated by photographs and vibration records on the failure of the P-47 rudder in the high-speed tunnel at a true speed of 468 miles per hour and a density corresponding to 9000 feet altitude. The fin-rudder unit was tested as being at least representative of the tail design of the P-47 airplane.

Report presenting values of the circulation function for dual-rotating propellers. Numerical values are given for four-, eight-, and twelve-blade dual-rotating propellers and for advance ratios from 2 to about 6.

Report presenting testing of the flutter characteristics of the SB2U model conducted after the model had been modified to lower its flutter speed. The model was tested to destruction and the flutter speed was measured throughout.

From Introduction: "The present report has been prepared to discuss the indications obtained from the University of Chicago turbulence indicator in relation to simultaneous measurement of atmospheric gustiness made by the NACA, which are summarized herein."

Wind-tunnel tests, investigating low drag wing performance in small-scale tests, showed a large increase in minimum drag coefficient, and a decrease of maximum lift coefficient occurred with decreasing Reynolds Number above certain designated values. The lift-curve slope varied up to 6% between high and low turbulence levels. Low Reynolds Number test data are unreliable for low drag airfoils either to estimate full-scale characteristics or to determine merits of airfoils for higher Reynolds numbers.

Report presenting tests of the low-speed lateral-control characteristics of an observation airplane with ailerons and spoilers in combination and with the spoilers disconnected and the ailerons used alone with various amounts of droop. The results indicated that in unstalled flight at low speeds and with flaps deflected, little or no aerodynamic benefit was derived by changing the lateral-control system from the aileron and spoiler combination to a normal aileron installation either with or without aileron droop.

Report discusses some unusual velocity-acceleration records on transport airplanes, which the report defines as "records of accelerations experienced in flight that resulted from causes other than atmospheric gusts" (from Summary). The analysis of the records, which is required for determining proper classification, is described, and the sorting of the records into gust- or maneuver-related is described. The report also discusses the importance of receiving this data from flight operators in addition to the routine information they provide.

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 presenting samples of 17S-T and 24S-T aluminum alloys subjected to accelerated corrosion tests in which the corrosion period was established at 6 hours for samples that had been etched to produce a uniform surface. The results indicate the types of corrosion attack, which are described in standard terminology, and may form a basis for estimating the resistance of the material to corrosion by a comparison of the relative depth and frequency of the corrosive attacks.

Report presenting an investigation to determine the permissible increase in engine power by using various internal coolants from the consideration of fuel knock and cylinder cooling. The internal coolants tested were water, 30-70 methyl alcohol-water volume percent mixture, 70-30 methyl alcohol-water volume percent mixture, methyl alcohol, and 80-20 ethyl alcohol-water volume percent mixture.

Report presenting measurements of a Consolidated B-24D airplane of accelerations at various points on the wing during landing impacts. landings were made with the wheels initially stationary but free to rotate, with the brakes set before contact, and with the main wheels rotating prior to contact.

Report discussing tests on three fuels in a 14-cylinder double-row radial air-cooled engine at different engine speeds, blower ratios, and spark settings.

Report presenting an analysis of the effect of power on the variation of stick-fixed neutral point with lift coefficient for several single-engine monoplanes. Testing occurred with the power off and with rated, climbing, or wave-off power and with flaps neutral and deflected. Results for these different conditions are provided.

Report discussing a comparison between a centrifugal-flow-type turbojet engine with an adjustable-area exhaust nozzle and with a series of fixed-area nozzles of various throat diameters. The adjustable-area nozzle was found to be as efficient as the fixed-area nozzles in testing. Information about the corrected static thrust, fuel flow, and tail-pipe gas temperature for both types of nozzles is provided.

Report presenting a series of boundary-layer surveys over the surface of an NACA 0012 airfoil at zero lift. Results regarding the pressure distribution, laminar boundary layer, transition, turbulent boundary layer, drag, and skin friction are provided.