1,264 Matching Results

Search Results

Low-Pressure Boundary-Layer Control in Diffusers and Bends

Description: Report presenting tests to study the effectiveness of small pressure differences in removing the dust boundary layer through slots in the duct wall of airplane ducts and reducing separation losses. Two-dimensional diffusers of 15 and 30 degrees included angles and some 90 degree bends were tested. The 30 degree diffuser was tested with and without an intercooler.
Date: April 1945
Creator: Biebel, William J.
Partner: UNT Libraries Government Documents Department

Measurement of Operating Stresses in an Aircraft Engine Crankshaft Under Power

Description: Report presenting strain-gage measurements made on the crankshaft of a Wright R-1820-73 test engine while under power. Bakelite-bonded wire strain gages were installed on the front half of the crankshaft and the connecting wires were brought out through the oil passages and connected to slip rings at the rear of the engine. The inertia-excited bending and tensile-compressive stresses increased almost directly with speed.
Date: February 1945
Creator: Walstrom, Douglas P.
Partner: UNT Libraries Government Documents Department

Flight Tests of Various Tail Modifications on the Brewster XSBA-1 Airplane 1: Measurements of Flying Qualities With Original Tail Surfaces

Description: 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.
Date: June 1943
Creator: Phillips, W. H. & Nissen, J. M.
Partner: UNT Libraries Government Documents Department

Flight Tests of Several Exhaust-Gas-to-Air Heat Exchangers in the B-17F Airplane

Description: Report presenting flight testing of seven exhaust-gas-to-air heat exchangers on a B-17F airplane to determine their performance characteristics and to investigate their flame-suppression qualities. Testing was conducted to secure performance data of heat exchangers which might be suitable for use in the thermal ice-prevention and cabin-heating system of the heavy bomber-type airplanes.
Date: April 1944
Creator: Look, Bonne C. & Selna, James
Partner: UNT Libraries Government Documents Department

Flight Tests of Thermal Ice-Prevention Equipment on a Lockheed 12A Airplane

Description: Report presenting a description of the development of thermal ice-prevention equipment by the application of a heated-air ice-prevention system to a Lockheed 12A airplane. Test data indicated that thermal ice-prevention equipment is practical and that the method of utilizing the exhaust gases as a source of heat is satisfactory.
Date: November 1943
Creator: Scherrer, Richard
Partner: UNT Libraries Government Documents Department

Lift and Drag Tests of Three Airfoil Models With Fowler Flaps Submitted by Consolidated Aircraft Corporation

Description: Report presenting lift and drag tests made in the two-dimensional tunnel of three airfoil models. The models represented intermediate sections on alternative wings of the XB-32 airplane and were equipped with 0.30 Fowler flaps. Results regarding the Davis model, the C.A.C. model, and low-drag model are provided.
Date: December 1941
Creator: Abbott, Ira H. & Turner, Harold R., Jr.
Partner: UNT Libraries Government Documents Department

Measurement of Free Water in Cloud Under Conditions of Icing

Description: "Measurements have been made, in flight, of the concentration of free water present in clouds under conditions of icing. These show the beneficial effect of kinetic heating in reducing the severity of those conditions, and permit the functioning of the thermal system for protecting airplanes against ice to be analyzed. The concentration of free water is deduced from measurements of the humidity of the air after the water had been vaporized" (p. 1).
Date: October 1944
Creator: Hardy, J. K.
Partner: UNT Libraries Government Documents Department

On the Flow of a Compressible Fluid by the Hodography Method 1: Unification and Extension of Present-Day Results

Description: Report presenting elementary basic solutions of the equations of motion of a compressible fluid in the hodograph variables are developed and used to provide a basis for comparison in the form of velocity correction formulas, of corresponding compressible and incompressible flows.
Date: March 1944
Creator: Garrick, I. E. & Kaplan, Carl
Partner: UNT Libraries Government Documents Department

Effect of Exhaust Back Pressure on Engine Power

Description: Report presenting data on the effect of exhaust back pressure on engine power for 14 aircraft engines. The data showed that the effect of exhaust back pressure on engine power varies with engine speed, range of back pressure and manifold pressure involved, and engine type. The only method of accurately determining the effect of back pressure on engine power than can currently be recommended is to test the specific engine type at the engine speed for which data are desired.
Date: June 1943
Creator: Pinkel, Benjamin
Partner: UNT Libraries Government Documents Department

Icing Tests of Aircraft-Engine Induction Systems

Description: Report presenting a program of icing tests conducted on an aircraft-engine induction system consisting of a Wright R-1820, G-200 blower section, Holley 1375-F carburetor and adapter, and specially built air scoop. The primary purpose of the investigation was to determine the effect of a number of possible factors on icing of engine-induction systems, including carburetor-air temperature, air-moisture content, water-droplet size, throttle opening, mixture ratio, rate of air flow, altitude, and others.
Date: January 1943
Creator: Kimball, Leo B.
Partner: UNT Libraries Government Documents Department

Heat-Transfer Tests of Several Engine Coolants

Description: Report presenting the relative cooling performance of water, commercial Prestone, and several ethylene-glycol and diethylene-glycol derivatives obtained from tests conducted with a small electrically heated heat exchanger.
Date: February 1945
Creator: Manganiello, E. J. & Stalder, J. R.
Partner: UNT Libraries Government Documents Department

Full-Scale-Tunnel Investigation of a Multiengine Pusher-Propeller Installation

Description: Report presenting an investigation of propellers designed specifically for pusher operation behind fixed contravanes on a large-scale model of a four-engine airplane. In the test, the wing trailing edge was twisted to serve as a contravane and to produce the rotating inflow required for optimum propulsive efficiency. Results indicated that gains in efficiency of about 3.5 percent at a blade angle of 40 degrees can be obtained by the use of contravanes with specifically designed pusher propellers.
Date: November 1942
Creator: Wilson, Herbert A., Jr.
Partner: UNT Libraries Government Documents Department

Heat-Transfer Tests of Two Steel Cylinder Barrels With Aluminum Fins Manufactured by Factory Production Method

Description: 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.
Date: August 1940
Creator: Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department

Compressibility and Heating Effects on Pressure Loss and Cooling of a Baffled Cylinder Barrel

Description: Report presenting testing to obtain experimental confirmation of the effect of air compressibility on cooling and pressure loss of a baffled cylinder barrel and to evaluate various methods of analysis. Testing occurred over a wide range of air flows and density altitudes.
Date: July 1944
Creator: Goldstein, Arthur W. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department

Determination of General Relations for the Behavior of Turbulent Boundary Layers

Description: Report presenting an analysis of data for turbulent boundary layers along wings and bodies of various shapes in order to determine the fundamental variables that control the development of turbulent boundary layers. Results indicate that the type of velocity distribution in the boundary layer could be expressed in terms of a single parameter.
Date: July 1943
Creator: von Doenhoff, Albert E. & Tetervin, Neal
Partner: UNT Libraries Government Documents Department

Critical Combinations of Longitudinal and Transverse Direct Stress for an Infinitely Long Flat Plate With Edges Elastically Restrained Against Rotation

Description: Report presenting a theoretical investigation of the buckling of an infinitely long flat plate with edges elastically restrained against rotation under combinations of longitudinal and transverse direct stress. Interaction curves are presented that give the critical combinations of stress for several different degrees of elastic edge restraint, including simple support and complete fixity.
Date: March 1946
Creator: Batdorf, S. B.; Stein, Manuel & Libove, Charles
Partner: UNT Libraries Government Documents Department

Effect of Mach Number on Position Error as Applied to a Pitot-Static Tube Located 0.55 Chord Ahead of an Airplane Wing

Description: "The effect on static-pressure measurements of locating a pitot-static tube 0.55 chord ahead of an airfoil section has been investigated. The tests were conducted in the NACA 24-inch high-speed tunnel on airfoil sections of various thickness ratios over a large range of Mach number. The results show that for a wing having a thickness ratio of 0.15 the measured Mach number, determined from a pitot-static-tube reading, is approximately 0.01 too low at a stream Mach number of 0.4 and approximately 0.03 too low at a Mach number of 0.8" (p. 1).
Date: May 1944
Creator: Lindsey, W. F.
Partner: UNT Libraries Government Documents Department

Notes on Maximum Airplane Angular Velocities

Description: Bulletin presenting some information on obtaining the maximum angular velocities to which aircraft are subjected in flight. Some of the maneuvers explored include pitching, rolling, yawing, or combinations of the motions, such as spinning.
Date: May 1943
Creator: Conway, H. M.
Partner: UNT Libraries Government Documents Department

On the Flow of a Compressible Fluid by the Hodography Method 2: Fundamental Set of Particular Flow Solutions of the Chaplygin Differential Equation

Description: Report presenting the utilization of the differential equation of Chaplygin's jet problem to give a systematic development of particular solutions of the hodograph flow equations, which extends the treatment of Chaplygin into the supersonic range and completes the set of particular solutions. The solutions serve to place on a reasonable basis the use of velocity correction formulas for the comparison of incompressible and compressible flows.
Date: November 1944
Creator: Kaplan, Carl
Partner: UNT Libraries Government Documents Department

Full-Scale Tunnel Tests of a Flying Model of the Curtiss XP-55 Airplane

Description: Report presenting testing in the full-scale tunnel to provide data for estimating the longitudinal stability and control characteristics of the Curtis XP-55 airplane. Testing included lift, drag, pitching-moment, hinge-moment, and elevator pressure measurements for various combinations of angle of attack, elevator deflection, and elevator tab settings. The results of the force tests and some correlation of the results of the force tests and the pressure measurements are presented in the report.
Date: January 1943
Creator: Biebel, William J.
Partner: UNT Libraries Government Documents Department