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Spin-Tunnel Tests of a 1/57.33-Scale Model of the Northrop XB-35 Airplane

Description: Report presenting testing of a model of the Northrop XB-35 airplane in the free-spinning tunnel in order to determine the spin characteristics and tumbling tendencies of the airplane. The spin tests indicated that for the normal loading condition, the model would not spin in the direction of the rudder for either the clean or the landing condition unless the wheel was set over with the rudder. Results regarding the spin tests in the clean condition, spin tests in the landing condition, tumbling… more
Date: April 1944
Creator: Kamm, Robert W. & Pepoon, Philip W.
Partner: UNT Libraries Government Documents Department
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Stability of a Body Stabilized by Fins and Suspended From an Airplane

Description: Report discusses the results of an investigation into the oscillations performed by suspended bodies like trailing airspeed heads and other towed devices. The most violent types of instability observed were found to be caused by unsteady or nonuniform air flow where the cable was lowered from the airplane. No method was found for reducing cable oscillations in short cable lengths, but the degree of stability present was considered satisfactory as long as the suspended body is lowered into a uni… more
Date: April 1944
Creator: Phillips, W. H.
Partner: UNT Libraries Government Documents Department
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Standardized Construction of Mine Ventilating Doors

Description: Report issued by the U.S. Bureau of Mines discussing the development and construction of ventilation doors in mine operations. The importance of functioning ventilating doors is presented. The construction process is described in detail. This report includes an illustration.
Date: April 1944
Creator: Hartley, J. C. & Moschetti, A. C.
Partner: UNT Libraries Government Documents Department
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Tests of 10 Inch 24S-T Aluminum-Alloy Shear Panels With 1-1/2 Inch Holes 2: Panels Having Holes With Notched Edges

Description: Report discusses the results of testing of 10-inch 24S-T aluminum alloy shear panels with 1.5 inch holes with notched edges to determine if a notch decreases the strength of the panel and if reinforcements can overcome the negative effects of the notch. The notch did appear to increase the stress concentration around the holes, but the lack of applicability to real-world scenarios is discussed.
Date: April 1944
Creator: Kuhn, Paul & Levin, L. Ross
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of a Beveled Aileron Shape Designed to Increase the Useful Deflection Range

Description: Report presenting a wind tunnel investigation of a beveled aileron shape designed to increase the useful deflection range. The purpose of the investigation was to determine the general aerodynamic characteristics of this aileron and, in particular, to determine its useful angular range. Results regarding the effect of the hinge-gap seal, the surface condition and Reynolds number, and effect of aileron profile are provided.
Date: April 1944
Creator: Jones, R. T. & Underwood, W. J.
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of Control-Surface Characteristics 16: Pressure Distribution Over an NACA 0009 Airfoil With 0.30-Airfoil-Chord Beveled-Trailing-Edge Flaps

Description: Report discusses pressure-distribution tests of a plain flap with interchangeable beveled trailing edges on an NACA 0009 airfoil. The flap chord was 30 percent of the airfoil chord and the bevel chords were 15 and 20 percent of the flap chord. The purpose of these tests was to supply pressure-distribution data that may be used for structural and aerodynamic design of horizontal and vertical tail surfaces.
Date: April 1944
Creator: Hoggard, H. Page, Jr. & Bulloch, Marjorie E.
Partner: UNT Libraries Government Documents Department
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Wind-tunnel investigation of control-surface characteristics 17: beveled-trailing-edge flaps of 0.20, 0.30, and 0.40 airfoil chord on an NACA 0009 airfoil

Description: Report presenting force tests in two-dimensional flow in the 4- by 6-foot vertical tunnel to determine the aerodynamic characteristics of an NACA 0009 airfoil with flaps having chord at 3 locations of the airfoil chord and three degrees of the beveled trailing edges. The results indicated that, with a smooth leading edge, the increased trailing-edge angle on the flaps with sealed gaps decreased the slope of the control-fixed lift curve and the lift effectiveness.
Date: April 1944
Creator: Lockwood, Vernard E.
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Procedure for Determination of Critical Stability and Control Characteristics of Airplanes

Description: "This report outlines the flight conditions that are usually critical in determining the design of components of an airplane which affect its stability and control characteristics. The wind-tunnel tests necessary to determine the pertinent data for these conditions are indicated, and the methods of computation used to translate these data into characteristics which define the flying qualities of the airplane are illustrated" (p. 1).
Date: April 1944
Creator: Goett, Harry J.; Jackson, Roy P. & Belsley, Steven E.
Partner: UNT Libraries Government Documents Department
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XC-35 Gust Research Project Analysis of Gust Measurements

Description: Report discusses measurements of gust size and intensity during the spring and summer of 1941 and 1942 under a variety of weather conditions and various altitudes up to 34,000 feet. Information about average gust-gradient distance, gust velocities, and gust frequency is included.
Date: April 1944
Creator: Moskovitz, A. I.
Partner: UNT Libraries Government Documents Department
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Viscosities and Densities of Fluorolube Oils

Description: Abstract: Since the viscosity-temperature relationships of fluorocarbons are somewhat unusual, when compared to hydrocarbons, for example, it was decided to measure the viscosities, at several temperatures, of various fluorolube oils. The calculation of the viscosity of a blend of oils is at best an uncertain operation, varying considerably with the method used. A comparison of various methods was indicated, in order that reasonably accurate values might be assumed for theoretical composites.… more
Date: April 28, 1943
Creator: Haendler, H. M.; Burger, L. L.; Sheldon, Z. D. & Barber, E. J.
Partner: UNT Libraries Government Documents Department
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Effect of Temperature on the Resonance Absorption of Neutrons by Uranium

Description: The resonance absorption of uranium for neutrons has been investigated between 20 degree C and 1000 degree C. Experiments were caried out on both UO2, density 4.63, and metal. The resonance activity was measured with respect to that of an iodine monitor at several different temperatures and the ratio of activity at temperature T to that at 20 degree C was determined. The increase in activity is 0.9 per cent per 100 degree C for the oxide and 1.1 percent per 100 degree C for the metal. The perio… more
Date: April 22, 1943
Creator: Mitchell, Allan C. G. (Allan Charles Gray), 1902-; Slotin, Louis; Marshall, John; Nedzel, V. A.; Brown, L. J. & Pruett, John R.
Partner: UNT Libraries Government Documents Department
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Review of Flight Tests of NACA C and D Cowlings on the XP-42 Airplane

Description: "Results of flight tests of the performance and cooling characteristics of three NACA D cowlings and of a conventional NACA D cowling on the XP-42 airplane are summarized and compared. The D cowling is, in general, characterized by the use of an annular inlet and diffuser section for the engine-cooling air. The D cowlings tested were a long-nose high-inlet-velocity cowling, a short-nose high-inlet-velocity cowling, and a short-nose low inlet-velocity cowling" (p. 371).
Date: April 20, 1943
Creator: Johnston, J. Ford
Partner: UNT Libraries Government Documents Department
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Determination of general relations for the behavior of turbulent boundary layers

Description: From Summary: "An analysis has been made of a considerable amount 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. It was found that the type of velocity distribution in the boundary layer could be expressed in terms of a single parameter. This parameter was chosen as the ratio of the displacement thickness to the momentum thickness of the boundary layer. The … more
Date: April 13, 1943
Creator: von Doenhoff, Albert E. & Tetervin, Neal
Partner: UNT Libraries Government Documents Department
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Jet-boundary corrections for reflection-plane models in rectangular wind tunnels

Description: A detailed method for determining the jet-boundary corrections for reflection-plane models in rectangular wind tunnels is presented. The method includes the determination of the tunnel span local distribution and the derivation of equations for the corrections to the angle of attack, the lift and drag coefficients, and the pitching-, rolling-, yawing-, and hinge-moment coefficients. The principle effects of aerodynamic induction and of the boundary-induced curvature of the streamlines have been… more
Date: April 13, 1943
Creator: Swanson, Robert S. & Toll, Thomas A.
Partner: UNT Libraries Government Documents Department
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Memorandum Listing the Areas in Colorado, Utah, Arizona and New Mexico that are Geologically Favorable for Developing Large Reserves of Vanadium Ore by Prospecting

Description: Introduction: Vanadium ore is being mined at many places in western Colorado, southeastern Utah, northeastern Arizona, and northwestern New Mexico (fig. 1). Eight mills in this region produced about 4,300,000 pounds of V2 05 in 1942, representing about 90 percent of the vanadium obtained from domestic sources. Although ore production has mostly exceeded mill capacity since 1937, production during the last half of 1942 averaged only about 19,000 tons or ore a month, whereas the capacity of these… more
Date: April 10, 1943
Creator: Fischer, R. P.
Partner: UNT Libraries Government Documents Department
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Formulas for propellers in yaw and charts of the side-force derivative

Description: General formulas are given for propellers for the rate of change of side-force coefficient with angle of yaw and for the rate of change of pitching-moment coefficient with angle of yaw. Charts of the side-force derivative are given for two propellers of different plan form. The charts cover solidities of two to six blades and single and dual rotation. The blade angle ranges from 15 degrees or 20 degrees to 60 degrees.
Date: April 7, 1943
Creator: Ribner, Herbert S.
Partner: UNT Libraries Government Documents Department
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Analysis of wind-tunnel stability and control tests in terms of flying qualities of full-scale airplanes

Description: From Introduction: "The purpose of this paper is to outline a suggested form of presentation of the results of a stability and control investigation in terms of flying qualities as defined in reference 1 and to systematize and review briefly the analytical work required for this type of presentation. No effort is made to specify definite test procedures."
Date: April 1, 1943
Creator: Kayten, Gerald G.
Partner: UNT Libraries Government Documents Department
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Diesel Engines Underground: [Part] 4. Effect on Composition of Exhaust Gas of Variables Influencing Fuel Injection

Description: Report issued by the Bureau of Mines over diesel engine operations. As stated in the introduction, "it is the purpose of this report to present such data and to reemphasize the importance of adequate maintenance for diesel engines used underground" (p. 2). This report includes tables, and illustrations.
Date: April 1943
Creator: Holtz, John C.; Berger, L. B.; Elliott, M. A. & Schrenk, H. H.
Partner: UNT Libraries Government Documents Department
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Effect of Varying Percentages of Exhaust Gas on Engine Performance

Description: "These tests were run to determine the effect that mixing engine exhaust gas with engine intake air has on fuel knock limit, specific fuel consumption, and air consumption." Information about the effect on pressure, air consumption, and fuel consumption is detailed.
Date: April 1943
Creator: Sanders, Newell D. & Barnett, Henry C.
Partner: UNT Libraries Government Documents Department
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Effect of Wing Leading-Edge Slots on the Spin and Recovery Characteristics of Airplanes

Description: Report presenting an investigation in the NACA 15-foot free-spinning tunnel to determine the effect of wing leading-edge slots on spin and recovery characteristics. The results indicate that recovery will generally be slower with the slots open than with them closed and the spin will be flatter and at a lower rate of descent.
Date: April 1943
Creator: Neihouse, Anshal I. & Pitkin, Marvin
Partner: UNT Libraries Government Documents Department
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Effects of a Typical Nacelle on the Characteristics of a Thick Low-Drag Airfoil Critically Affected by Leading-Edge Roughness

Description: Report presenting testing to study the effects of a typical nacelle on the characteristics of a thick low-drag airfoil that was shown to be subject to separation difficulties due to leading edge roughness. This testing confirmed the results of previous tests which indicated that the airfoil was unconservative with respect to separation difficulties. Results regarding the internal-flow measurements and corresponding drag increments, external drag, leading-edge roughness and nacelle combination, … more
Date: April 1943
Creator: Ellis, Macon C., Jr.
Partner: UNT Libraries Government Documents Department
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Experimental Investigation of a Model of a Two-Stage Turboblower

Description: "In the present paper an investigation is made of two stages of a multistage turboblower having a vaneless diffuser behind the impeller and guide vanes at the inlet to the nest stage. The method employed was that of investigating the performance of the successive elements of the blower (the impeller, vaneless diffuser, ets.) whereby the kinematics of the flow through the blower could be followed and the pressure at the different points computed. The character of the flow and the physical signif… more
Date: April 1943
Creator: Dovjik, S. & Polikovsky, W.
Partner: UNT Libraries Government Documents Department
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