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 presenting aerodynamic tests of a 300-pound M-31 demolition bomb. Force tests at a range of angles of attack were made at Mach number 0.725, which corresponds to a speed of 810 feet per second at sea level. Results regard the drag, lift, and pitching moment are provided.

Report presenting an investigation to determine the effect of the location of the diffuser vanes with respect to the supercharger outlets and the effect of flow conditions at the impeller inlet on the air-flow distribution in the outlets of the engine-stage supercharger of an 18-cylinder double-row radial aircraft engine. The effect of flow conditions at the impeller inlet was investigated by distorting the flow at the inlet and noting the effect in the supercharger outlets. Results regarding the diffuser effect and inlet effect are provided.

From Introduction: "The tests reported herein, conducted during the early part of 1945, were made to determine the inherent charge-air distribution characteristics of the engine-stage supercharger of the double-row radial engine."

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."

"The data presented in this report are part of a general program to determine the effects of xylidines on the knock-limited performance of currently used aviation fuels" (p. 2).

Report discusses the results of a study "of the requirements for the attainment of a straight-line trajectory for a preset guided missile in the presence of wind or target motion" (from Summary). Information about the straight-line trajectory, position of the launching airplane, straight-line collision course, and arrangement of the autopilot in the missile is provided. Recommendations are also made about the creation of a bombsight mounting for the pilot of the launching airplane in order to attain the desired straight-line collision course.

"The lateral- and directional-stability and -control characteristics of a twin-engine patrol airplane as predicted from the results of wind-tunnel tests of a powered model and as measured in flight are compared in this report. The predictions from wind-tunnel-test data were in good agreement with the flight-test results. The results show that such predicted flying-qualities characteristics are sufficiently accurate to indicate the unsatisfactory lateral- and directional-stability and -control characteristics of airplanes in the preliminary design stage" (p. 1).

"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 tests made with a dynamic model of the Army B-26 airplane to determine its behavior when landed on water. Results regarding the general behavior, effect of flaps, effect of landing attitude and speed, tests with undamaged model, tests with simulated damage, tests with propellers, vertical decelerations, and effect of weight are provided.

This report presents the results of a flight investigation to determine the effect on the performance of a turbosupercharged engine of an exhaust-gas-to-air heat exchanger installed between the engine-exhaust collector ring and the turbosupercharger. The background, results, and discussion of the investigation are described.

An investigation was conducted to determine the effect of a coolant solution of 25 percent ethyl alcohol, 25 percent methyl alcohol, and 50 percent water by volume and maximum-economy spark advance on knock-limited performance and fuel economy of a large air-cooled cylinder. The knock-limited performance of the cylinder at engine speeds of 2100 and 2500 rpm was determined for coolant-fuel ratios of 0.0, 0.2, and 0.4. The effect of water-alcohol injection on fuel economy was determined in constant charge-air flow tests. The tests were conducted at a spark advance of 20 deg B.T.C. and maximum-economy spark advance.

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 presenting tests to determine the effect of xylidines on the stability of an aircraft-engine lubricating oil. The Indiana oxidation test and measurements of the oxygen absorption rate of the oil samples were performed on Navy 1120 oil, Navy 1120 oil plus 0.5 percent by weight of xylidines, and Navy 1120 oil used in piston-ring-sticking tests both with and without xylidines. Results regarding the Indiana oxidation test, the Davis oxidation test, the automatic oil-oxidation apparatus, and a laboratory inspection are provided.

Report presenting a full-size single-engine pursuit airplane, with wing tips cut off, tested in the 16-foot wind tunnel. The purpose was to find means for eliminating an extreme rumble which occurred at high speeds when the radiator air-duct-exit openings were small. Results regarding rumble, cooling air, and drag are provided.

Data are presented of the flow conditions in the vicinity of an NACA D sub S -type cowling. Tests were made of a 1/2 scale-nacelle model at inlet-velocity ratios ranging from 0.23 to 1.02 and angles of attack from 6 deg to 10 deg. The velocity and direction of flow in the vertical plane of symmetry of the cowling were determined from orifices and tufts installed on a board aligned with the flow. Diagrams showing velocity ratio contours and lines of constant flow angles are given.

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.

"A comparison has been made in flight of the antiknock characteristics of 33-R fuel with that of 28-R and a triptane blend. The knock-limited performance of the three fuels - 33-R, a blend of 80 percent 28-R plus 20 percent triptane (leaded to 4.5 ml TEL/gal), and 28-R - was investigated in two modified 14-cylinder double-row radial air-cooled engines. Tests were conducted on the engines as installed in the left inboard nacelle of an airplane. A carburetor-air temperature of approximately 85 deg F was maintained" (p. 1).

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.

Report presenting an investigation of the suitability of 27 aromatic amines for overwater storage of their gasoline blends. The program is also meant to determine the antiknock effectiveness and low-temperature solubility in gasoline.

Supplement using data from a previous report to show the cargo that can be carried at various ranges, pounds of cargo that can be carried per pound of fuel, and other graphs to simplify the problem of determining which cargo can be carried at any range. The assumptions, parameters, and equations from the original report are carried over in the supplement.

Report presenting a study of the performance of bombers powered by two, four, and six 3000-horsepower engines supercharged to 35,000 feet. The performances are computed and are based on drag coefficients equal to the best obtained on modern airplanes and on weight estimates obtained from modern Army Air Forces airplanes. A chart is provided with the coordinates of power loading and wing loading noted so that all performances can be compared.

Report presenting tests conducted on a steel cylinder barrel with aluminum fins in order to determine the heat-transfer coefficients of the cylinder and the excellence of the bond between the steel barrel and the aluminum fins. Results regarding the heat-transfer tests and physical tests are provided.

Report presenting testing of two engine cylinder barrels with aluminum fins. The primary purpose was to determine the heat-transfer coefficients and the excellence of the bonds between the aluminum fins and the aluminum base and between the aluminum base and the steel of the two barrels when manufactured by a large-volume production method.