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The Aerodynamic Forces and Moments Exerted on a Spinning Model of the NY-1 Airplane as Measured by the Spinning Balance

Description: From Summary: "A preliminary investigation of the effects of changes in the elevator and rudder settings and of small changes in attitude upon the aerodynamic forces and moments exerted upon a spinning airplane was undertaken with the spinning balance in the 5-foot vertical tunnel of the National Advisory Committee for Aeronautics. The tests were made on a 1/12-scale model of the "NY-1" airplane. Data by which to fix the attitude, the radius of spin, and the rotational and air velocities were t… more
Date: February 7, 1933
Creator: Bamber, M. J. & Zimmerman, C. H.
Partner: UNT Libraries Government Documents Department
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Analysis of Turbulent Heat Transfer, Mass Transfer, and Friction in Smooth Tubes at High Prandtl and Schmidt Numbers

Description: From Introduction: "In the analysis given herein, which was made at the NACA Lewis laboratory, the expression for eddy diffusivity given in reference 1 is modified in order to account for the effect of kinematic viscosity in reducing the turbulence in the region close to the wall. The effects of variable viscosity and of length-to-diameter ratio are also investigated."
Date: February 17, 1954
Creator: Deissler, Robert G.
Partner: UNT Libraries Government Documents Department
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Comparative flight performance with an NACA Roots supercharger and a turbocentrifugal supercharger

Description: This report presents the comparative flight results of a roots supercharger and a turbocentrifugal supercharger. The tests were conducted using a modified DH-4M2 airplane. The rate of climb and the high speed in level flight of the airplane were obtained for each supercharger from sea level to the ceiling. The unsupercharged performance with each supercharger mounted in place was also determined. The results of these tests show that the ceiling and rate of climb obtained were nearly the same fo… more
Date: February 25, 1930
Creator: Schey, Oscar W. & Young, Alfred W.
Partner: UNT Libraries Government Documents Department
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The comparative performance of an aviation engine at normal and high inlet air temperatures

Description: "This report presents some results obtained during an investigation to determine the effect of high inlet air temperature on the performance of a Liberty 12 aviation engine. The purpose of this investigation was to ascertain, for normal service carburetor adjustments and a fixed ignition advance, the relation between power and temperature for the range of carburetor air temperatures that may be encountered when supercharging to sea level pressure at altitudes of over 20,000 feet and without int… more
Date: February 11, 1927
Creator: Gardiner, Arthur W. & Schey, Oscar W.
Partner: UNT Libraries Government Documents Department
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The Compressible Laminar Boundary Layer with Heat Transfer and Arbitrary Pressure Gradient

Description: "An approximate method for the calculation of the compressible laminar boundary layer with heat transfer and arbitrary pressure gradient, based on Thwaites' correlation concept, is presented. With the definition of dimensionless shear and heat-transfer parameters and an assumed correlation of these parameters in terms of a momentum parameter, a complete system of relations for calculating skin friction and heat transfer results. Knowledge of velocity or temperature profiles is not necessary in … more
Date: February 1, 1955
Creator: Cohen, Clarence B. & Reshotko, Eli
Partner: UNT Libraries Government Documents Department
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Contributions on the Mechanics of Boundary-Layer Transition

Description: "The manner in which flow in a boundary layer becomes turbulent was investigated on a flat plate at wind speeds generally below 100 feet per second. Hot-wire techniques were used, and many of the results are derived from oscillograms of velocity fluctuations in the transition region. Following a presentation of the more familiar aspects of transition, there are presented the very revealing facts discovered while studying the characteristics of artificially produced turbulent spots" (p. 853).
Date: February 28, 1955
Creator: Schubauer, G. B. & Klebanoff, P. S.
Partner: UNT Libraries Government Documents Department
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Determination of vortex paths by series expansion technique with application to cruciform wings

Description: A series method of determining two-dimensional vortex paths is considered and applied to the computation of vortex positions behind a slender equal-span cruciform wing at any angle of bank as a function of the distance behind the trailing edge. Calculated paths are shown for four bank angles. For a bank angle of 45 degrees comparison is made with the results of a closed expression given in NACA-TN-2605. For other bank angles water-tank experiments provide qualitative comparison. Satisfactory ag… more
Date: February 8, 1956
Creator: Alksne, Alberta Y.
Partner: UNT Libraries Government Documents Department
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Differential equations of motion for combined flapwise bending, chordwise bending, and torsion of twisted nonuniform rotor blades

Description: The differential equations of motion for the lateral and torsional deformations of twisted rotating beams are developed for application to helicopter rotor and propeller blades. No assumption is made regarding the coincidence of the neutral, elastic, and mass axes, and the generality is such that previous theories involving various simplifications are contained as subcases to the theory presented in this paper. Special attention is given the terms which are not included in previous theories. Th… more
Date: February 1957
Creator: Houbolt, John C. & Brooks, George W.
Partner: UNT Libraries Government Documents Department
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The drag of airplane wheels, wheel fairings, and landing gears - 1

Description: This report presents the results of tests made in the 7-by 10-foot wind tunnel and in the 20-foot tunnel of the National Advisory Committee for Aeronautics to determine the drag of a number of airplane wheels, wheel fairings, and landing gears designed or selected for an airplane of 3,000 pounds gross weight. All tests were made on full-size models; those in the 7-by 10-foot tunnel were made at air speeds up to 80 miles per hour and those in the 20-foot tunnel were made at air speeds up to 100 … more
Date: February 9, 1934
Creator: Herrnstein, William H., Jr. & Biermann, David
Partner: UNT Libraries Government Documents Department
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Effect of Aging on Mechanical Properties of Aluminum-Alloy Rivets

Description: "Curves and tabular data present the results of strength tests made during and after 2 1/2 years of aging on rivets and rivet wire of 3/16-inch nominal diameter. The specimens were of aluminum alloy: 24s, 17s, and a17s of the duralumin type and 53s of the magnesium-silicide type" (p. 353).
Date: February 7, 1941
Creator: Roop, Frederick C.
Partner: UNT Libraries Government Documents Department
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Effect of Aspect Ratio on the Low-Speed Lateral Control Characteristics of Untapered Low-Aspect-Ratio Wings Equipped With Flap and With Retractable Ailerons

Description: A low-speed wind-tunnel investigation was made to determine the lateral control characteristics of a series of untapered low-aspect-ratio wings. Sealed flap ailerons of various spans and spanwise locations were investigated on unswept wings of aspect ratios 1.13, 1.13, 4.13, and 6.13; and various projections of 0.60-semispan retractable ailerons were investigated on the unsweptback wings of aspect ratios 1.13, 2.13, and 4.13 and on a 45 degree sweptback wing. The retractable ailerons investigat… more
Date: February 8, 1952
Creator: Fischel, Jack; Naeseth, Rodger L.; Hagerman, John R. & O'Hare, William M.
Partner: UNT Libraries Government Documents Department
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The Effect of Humidity on Engine Power at Altitude

Description: "From tests made in the altitude chamber of the Bureau of Standards, it was found that the effect of humidity on engine power is the same at altitudes up to 25,000 feet as at sea level. Earlier tests on automotive engines, made under sea-level conditions, showed that water vapor acts as an inert diluent, reducing engine power in proportion to the amount of vapor present. By combining the effects of atmospheric pressure, temperature, and humidity, it is shown that the indicated power obtainable … more
Date: February 24, 1932
Creator: Brooks, D. B. & Garlock, E. A.
Partner: UNT Libraries Government Documents Department
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Effect of moderate air flow on the distribution of fuel sprays after injection cut-off

Description: "High-speed motion pictures were taken of fuel sprays with the NACA spray-photographic apparatus to study the distribution of the liquid fuel from the instant of injection cut-off until about 0.05 second later. The fuel was injected into a glass-walled chamber in which the air density was varied from 1 to 13 times atmospheric air density (0.0765 to 0.99 pound per cubic foot) and in which the air was at room temperature. The air in the chamber was set in motion by means of a fan, and was directe… more
Date: February 14, 1934
Creator: Rothrock, A. M. & Spencer, R. C.
Partner: UNT Libraries Government Documents Department
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The effect of nozzle design and operating conditions on the atomization and distribution of fuel sprays

Description: The atomization and distribution characteristics of fuel sprays from automatic injection valves for compression-ignition engines were determined by catching the fuel drops on smoked-glass plates, and then measuring and counting the impressions made in the lampblack. The experiments were made in an air-tight chamber in which the air density was raised to values corresponding to engine conditions.
Date: February 19, 1932
Creator: Lee, Dana W.
Partner: UNT Libraries Government Documents Department
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The effect of valve timing upon the performance of a supercharged engine at altitude and an unsupercharged engine at sea level

Description: This investigation was conducted to determine the comparative effects of valve timing on the performance of an unsupercharged engine at sea level and a supercharged engine at altitude. The tests were conducted on the NACA universal test engine. The timing of the four valve events was varied over a wide range; the engine speeds were varied between 1,050 and 1,500 r.p.m.; the compression ratios were varied between 4.35:1 and 7.35:1. The conditions of exhaust pressure and carburetor pressure of a … more
Date: February 4, 1931
Creator: Schey, Oscar W. & Biermann, Arnold E.
Partner: UNT Libraries Government Documents Department
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Equilibrium Operating Performance of Axial-Flow Turbojet Engines by Means of Idealized Analysis

Description: "A method of predicting equilibrium operating performance of turbojet engines has been developed, with the assumption of simple model processes for the components. Results of the analysis are plotted in terms of dimensionless parameters comprising critical engine dimensions and over-all operating variables. This investigation was made of an engine in which the ratio of axial inlet-air velocity to compressor-tip velocity is constant, which approximates turbojet engines with axial-flow compressor… more
Date: February 25, 1949
Creator: Sanders, John C. & Chapin, Edward C.
Partner: UNT Libraries Government Documents Department
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Experiments on the distribution of fuel in fuel sprays

Description: The distribution of fuel in sprays for compression-ignition engines was investigated by taking high-speed spark photographs of fuel sprays reproduced under a wide variety of conditions, and also by injecting them against pieces of plasticine. A photographic study was made of sprays injected into evacuated chambers, into the atmosphere, into compressed air, and into transparent liquids. Pairs of identical sprays were injected counter to each other and their behavior analyzed. Small high velocity… more
Date: February 13, 1932
Creator: Lee, Dana W.
Partner: UNT Libraries Government Documents Department
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Exploratory investigation of boundary-layer transition on a hollow cylinder at a Mach number of 6.9

Description: Report presenting an investigation of the Reynolds number for transition on the outside of a hollow cylinder with heat transfer from the boundary layer to the wall at Mach number 6.9. At a given Mach number, it appears that the Reynolds number based on leading-edge thickness is an important parameter in comparisons of flat-plate transition data from various installations.
Date: February 9, 1956
Creator: Bertram, Mitchel H.
Partner: UNT Libraries Government Documents Department
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A Flight Investigation of the Spinning of the F4B-2 Biplane with Various Loads and Tail Surfaces

Description: "A flight investigation of the spinning of the F4B-2 single-seat fighter airplane was made for the purpose of finding modifications that would eliminate dangerous spin tendencies exhibited by this type of airplane in service. The effects on steady spins and on recoveries of changing the loading, enlarging the fin areas, changing the elevator plan form, and raising the horizontal surfaces, were determined" (p. 413).
Date: February 12, 1935
Creator: Scudder, N. F. & Seidman, Oscar
Partner: UNT Libraries Government Documents Department
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Flow coefficients of monosleeve valves

Description: The flow coefficients of the intake and the exhaust ports of a sleeve-valve cylinder were measured by attaching the cylinder to a large tank and measuring the changes in pressure and temperature in the tank that were caused by short periods of air flow through the valve ports. The derivation of the equations on which the flow coefficients are based is given. The distribution of total pressure in the arms of the sleeve-valve intake manifold was measured. The arms are found to have as little as 7… more
Date: February 8, 1940
Creator: Waldron, C. D.
Partner: UNT Libraries Government Documents Department
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The Forces and Moments Acting on Parts of the XN2Y-1 Airplane During Spins

Description: "The magnitudes of the yawing moments produced by various parts of an airplane during spins have previously been found to be of major importance in determining the nature of the spin. Discrepancies in resultant yawing moments determined from model and full-scale tests, however, have indicated the probable importance of scale effect on the model. In order to obtain data for a more detailed comparison between full-scale and model results, flight tests were made to determine the yawing moments con… more
Date: February 20, 1936
Creator: Scudder, N. F.
Partner: UNT Libraries Government Documents Department
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Friction, wear, and surface damage of metals as affected by solid surface films

Description: "As predicted by friction theory, experiments showed that friction and surface damage of metals can be reduced by solid surface films. The ability of materials to form surface films that prevent welding was a very important factor in wear of dry and boundary lubricated surfaces. Films of graphitic carbon on cast irons, NiO on nickel alloys, and FeO and Fe(sub 3)O(sub 4) on ferrous materials were found to be beneficial. Abrasive films such as Fe(sub 2)O(sub 3) or MoO(sub 3) were definitely detri… more
Date: February 10, 1955
Creator: Bisson, Edmond E.; Johnson, Robert L.; Swikert, Max A. & Godfrey, Douglas
Partner: UNT Libraries Government Documents Department
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Ground Simulator Studies of the Effects of Valve Friction, Stick Friction, Flexibility, and Backwash on Power Control System Quality

Description: Report presents results of tests made on a power control system by means of a ground simulator to determine the effects of various combinations of valve friction and stick friction on the ability of the pilot to control the system. Various friction conditions were simulated with a rigid control system, a flexible system, and a rigid system having some backlash. For the tests, the period and damping of the simulated airplane were held constant.
Date: February 8, 1957
Creator: Brown, B. Porter
Partner: UNT Libraries Government Documents Department
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Horizontal tail loads in maneuvering flight

Description: From Summary: "A method is given for determining the horizontal tail loads in maneuvering flight. The method is based upon the assignment of a load-factor variation with time and the determination of a minimum time to reach peak load factor. The tail load is separated into various components. Examination of these components indicated that one of the components was so small that it could be neglected for most conventional airplanes; therefore, the number of aerodynamic parameters needed in this … more
Date: February 9, 1950
Creator: Pearson, Henry A.; McGowan, William A. & Donegan, James J.
Partner: UNT Libraries Government Documents Department
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