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Approximate Formulas for the Computation of Turbulent Boundary-Layer Momentum Thicknesses in Compressible Flows

Description: Report presenting approximate formulas for the computation of the momentum thickness of turbulent boundary layers on two-dimensional bodies, on bodies of revolution at zero angle of attack, and on the inner surfaces of round channels all in compressible flow given in the form of integrals that can be conveniently computed. Results for skin-friction formulas, laminar boundary layers, and full thickness of boundary layer are provided.
Date: March 1946
Creator: Tetervin, Neal
Partner: UNT Libraries Government Documents Department
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Determination of Flight Paths of an SBD-1 Airplane in Simulated Diving Attacks, Special Report

Description: An investigation has been made to determine the motions of and the flight paths describe by a Navy dive-bombing airplane in simulated diving attacks. The data necessary to evaluate these items, with the exception of the atmospheric wind data, were obtained from automatic recording instruments installed entirely within the airplane. The atmospheric wind data were obtained from the ground by the balloon-theodolite method. The results of typical dives at various dive angles are presented in the fo… more
Date: March 1943
Creator: Johnson, Harold I.
Partner: UNT Libraries Government Documents Department
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Development of Wing Inlets

Description: Lift, drag, internal flow, and pressure distribution measurements were made on a low-drag airfoil incorporating various air inlet designs. Two leading-edge air inlets are developed which feature higher lift coefficients and critical Mach than the basic airfoil. Higher lift coefficients and critical speeds are obtained for leading half of these inlet sections but because of high suction pressures near exist, slightly lower critical speeds are obtained for the entire inlet section than the basic … more
Date: March 1946
Creator: Racisz, Stanley F.
Partner: UNT Libraries Government Documents Department
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An Electron and X-Ray Diffraction Investigation of Surface Changes on Nitrided-Steel Piston Rings During Engine Operation in Nitrided-Steel Cylinders Barrels

Description: Report presenting an examination of new and used nitrided-steel piston rings by electron and X-ray diffraction in a study of the surface changes produced during engine operation. Both new and used rings, examined after degreasing, gave an electron-diffraction pattern consisting of diffuse bands: those from used rings fell at the usual positions of the bands from polished metal surfaces.
Date: March 1945
Creator: Good, J. N. & Brockway, L. O.
Partner: UNT Libraries Government Documents Department
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Estimation of Critical Speeds of Airfoils and Streamline Bodies

Description: Report presenting methods and charts for estimating the critical compressibility speeds of a large number of airfoils and streamline bodies. The systematic effects of thickness, thickness distribution, camber, camber location, leading-edge radius, and lift coefficient are considered. The results indicate that with a given lift coefficient, the thickness of the airfoil or of the body is the primary factor controlling its critical speed.
Date: March 1940
Creator: Robinson, Russell G. & Wright, Ray H.
Partner: UNT Libraries Government Documents Department
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An Experimental Investigation of Several Low-Drag Wing-Nacelle Combinations with Internal Air Flow

Description: From Summary: "The results of an experimental investigation of several low-drag wing-nacelle combinations, incorporating internal air-flow systems, are presented. The external-drag increments due to these nacelles are between one-half and two-thirds of those of conventional nacelle forms. This improvement is accomplished with only minor effects on the lift and moment characteristics of the wing. The procedure employed to determine the external shape of such low-drag nacelles is considered in de… more
Date: March 1945
Creator: Allen, H. Julian; Frick, Charles W. & Erickson, Myles D.
Partner: UNT Libraries Government Documents Department
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Experimental Study of the Coating Formed on Nitrided-Steel Piston Rings During Operation in Nitrided-Steel Cylinders

Description: Report presenting a study of nitrided-steel piston rings in nitrided-steel cylinder barrels, which showed material of high reflectivity on their running faces. The structure of the material could not be resolved at a magnification of 1500 diameters. Results regarding the occurrence of coating, thickness of coating, height of coating above the nominal surface, chemical characteristics, physical characteristics, metallurgical change, and additional tests are provided.
Date: March 1944
Creator: Bobrowsky, A. R.; Kittel, J. Howard & Boegli, Charles P.
Partner: UNT Libraries Government Documents Department
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Flight Investigation at High Speeds of Profile Drag of Wing of a P-47d Airplane Having Production Surfaces Covered With Camouflage Paint

Description: Report presenting a flight investigation made at high speeds to determine the profile drag of a P-47D airplane wing with production surfaces covered with camouflage paint. The results indicated that a minimum profile-drag coefficient of 0.0097 was attained for lift coefficients from 0.16 to 0.25 at Mach numbers less than 0.67.
Date: March 1946
Creator: Zalovcik, John A. & Daum, Fred L.
Partner: UNT Libraries Government Documents Department
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Flight Investigation at High Speeds of Profile Drag of Wing of a P-47D Airplane Having Production Surfaces Covered with Camouflage Paint

Description: Wing section outboard of flap was tested by wake surveys in Mach range of 0.25 - 0.78 and lift coefficient range 0.06 - 0.69. Results indicated that minimum profile-drag coefficient of 0.0097 was attained for lift coefficients from 0.16 to 0.25 at Mach less than 0.67. Below Mach number at which compressibility shock occurred, variations in Mach of 0.2 had negligible effect on profile drag coefficient. Shock was not evident until critical Mach was exceeded by 0.025.
Date: March 1946
Creator: Zalovcik, John A. & Daum, Fred L.
Partner: UNT Libraries Government Documents Department
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High Temperature Characteristics of 17 Alloys at 1200 and 1350 Degrees F

Description: Report presenting the results of a study of the rupture-test characteristics of 13 wrought and 4 cast alloys which were considered to have promise for service in exhaust gas turbines. The results are given in the forms of a table of information and data, a page of curves, and a page of photomicrographs.
Date: March 1944
Creator: Freeman, J. W.; Rote, F. B. & White, A. E.
Partner: UNT Libraries Government Documents Department
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A Metallurgical Investigation of a Large Forged Disc of 19-9 DL Alloy

Description: Report presenting an investigation of the properties of a 20-inch diameter by 3.25 inch disc of 19-9 DL alloy in the as-forged and stress-relieved condition. Results regarding the hardness survey, short-time tensile properties, rupture test characteristics, time for deformation characteristics under stress, creep strengths, and stability characteristics are provided.
Date: March 1945
Creator: Freeman, J. W.; Reynolds, E. E. & White, A. E.
Partner: UNT Libraries Government Documents Department
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A method for the calculation of external lift, moment, and pressure drag of slender open-nose bodies of revolution at supersonic speeds

Description: Report presenting a method for the calculation of the external lift, moment, and pressure drag of slender open-nose bodies of revolution at supersonic speeds. The lift, moment, and pressure drag of a typical ramjet body shape are calculated at several Mach numbers. Results regarding the results of the calculations, comparison with experiment, and another application of the method are provided.
Date: March 1946
Creator: Parker, Hermon M.
Partner: UNT Libraries Government Documents Department
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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
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Preliminary Report on the Characteristics of the N.A.C.A. 4400R Series Airfoils

Description: Report presenting tests made in the variable-density wind tunnel of airfoils of the NACA 4400 series modified by reflex at the trailing edge designed to reduce the pitching moment to the value of -0.03. The modified airfoils are designated the NACA 4400R series.
Date: March 1939
Creator: Sherman, Albert
Partner: UNT Libraries Government Documents Department
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Summary of Airfoil Data

Description: From Summary: "Recent airfoil data for both flight and wind-tunnel tests have been collected and correlated insofar as possible. The flight data consist largely of drag measurements made by the wake-survey method. Most of the data on airfoil section characteristics were obtained in the Langley two-dimensional low-turbulence pressure tunnel. Detail data necessary for the application of NACA 6-serles airfoils to wing design are presented in supplementary figures, together with recent data for the… more
Date: March 1945
Creator: Stivers, Louis S.; Abbott, Ira H. & von Doenhoff, Albert E.
Partner: UNT Libraries Government Documents Department
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The Supersonic Axial-Flow Compressor

Description: "An investigation has been made to explore the possibilities of axial-flow compressors operating with supersonic velocities into the blade rows. Preliminary calculations showed that very high pressure ratios across a stage, together with somewhat increased mass flows, were apparently possible with compressors which decelerated air through the speed of sound in their blading. The first phase of the investigation was the development of efficient supersonic diffusers to decelerate air through the … more
Date: March 8, 1946
Creator: Kantrowitz, Arthur
Partner: UNT Libraries Government Documents Department
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Theory and Application of Hot-Wire Instruments in the Investigation of Turbulent Boundary Layers

Description: Report presenting an account of the recent developments in hot-wire instruments for use in turbulent boundary layers to determine the magnitude of the several components of the turbulent velocity fluctuations together with the correlation between them and turbulent shearing stress.
Date: March 1946
Creator: Schubauer, G. B. & Klebanoff, P. S.
Partner: UNT Libraries Government Documents Department
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Wind-tunnel investigation of plain ailerons for a wing with a full-span flap consisting of an inboard Fowler and an outboard retractable split flap

Description: Report presenting an investigation in the 7- by 10-foot wind tunnel of three plain ailerons on an NACA 23012 wing with full-span combinations of Fowler and split-type flaps. Static rolling, yawing, and hinge moments were determined and are presented for several angles of attack and flap deflection. The results indicated that a plain sealed aileron with internal balance will provide lateral control for airplanes equipped with full-span combinations of slotted and split-type flaps.
Date: March 1941
Creator: Harris, Thomas A. & Purser, Paul E.
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of Shielded Horn Balances and Tabs on a 0.7-Scale Model of XF6F Vertical Tail Surface

Description: Results of subject tests indicate the difficulty of obtaining closely balanced rudder surfaces for most tail assemblies with shielded horns and maintaining a near zero rate-of-change of hinge-moment coefficient without an additional balancing device. A comparison is made between shielded and unshielded horn test results. Pressure distribution and tuft tests of flow over different shaped horns showed higher critical speed for medium-taper nosed horn. The trim tab nose shape had little effect on … more
Date: March 1944
Creator: Lowry, John G.; Maloney, James A. & Garner, I. Elizabeth
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of Trimming Tabs on a Thickened and Beveled Aileron on a Tapered Low-Drag Wing

Description: Report presenting an investigation in the 7- by 10-foot tunnel of three inset tabs and of one attached tab on the beveled aileron of a low-drag wing. The results indicated that, of the arrangements tested, an inset tab with a chord 50 percent of the aileron chord provided the most satisfactory trimming characteristics on a beveled aileron.
Date: March 1943
Creator: Rogallo, F. M. & Crandall, Stewart M.
Partner: UNT Libraries Government Documents Department
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Wing-Fuselage Interference - Comparison of Conventional and Airfoil-Type-Fuselage Combinations

Description: Report presenting tests of wing-fuselage combinations employing an airfoil-type fuselage in the variable-density wind tunnel as part of a wing-fuselage program. The models were designed to simulate an existing moderate-size transport airplane of that type. Results regarding some general comparisons, lift distribution and induced drag, and drag in high-speed flight are provided.
Date: March 1937
Creator: Jacobs, Eastman N. & Sherman, Albert
Partner: UNT Libraries Government Documents Department
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