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Nomenclature for Aeronautics

Description: The nomenclature for aeronautics presented in this Report No. 474 is a revision of the last previous report on this subject (i.e., Report no. 240.) This report is published for the purpose of encouraging greater uniformity and precision in the use of terms relating to aeronautics, both in official documents of the Government and in commercial publications. Terms in general use in other branches of engineering have been included only where they have some special significance in aeronautics, or f… more
Date: 1939
Partner: UNT Libraries Government Documents Department
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Aircraft rate-of-climb indicators

Description: From Summary: "The theory of the rate-of-climb indicator is developed in a form adapted for application to the instrument in its present-day form. Certain dynamic effects, including instrument lag, and the use of the rate-of-climb indicator as a statoscope are also considered. Modern instruments are described. A laboratory test procedure is outlined and test results are given."
Date: 1939
Creator: Johnson, Daniel P.
Partner: UNT Libraries Government Documents Department
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Determination of the Profile Drag of an Airplane Wing in Flight at High Reynolds Numbers

Description: "Flight tests were made to determine the profile-drag coefficients of a portion of the original wing surface of an all-metal airplane and of a portion of the wing made aerodynamically smooth and more nearly fair than the original section. The wing section was approximately the NACA 2414.5. The tests were carried out over a range of airplane speeds giving a maximum Reynolds number of 15,000,000. Tests were also carried out to locate the point of transition from laminar to turbulent boundary laye… more
Date: January 6, 1939
Creator: Bicknell, Joseph
Partner: UNT Libraries Government Documents Department
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Calculation of the Aerodynamic Characteristics of Tapered Wings With Partial-Span Flaps

Description: "Factors derived from wing theory are presented. By means of these factors, the angle of zero lift, the lift-curve slope, the pitching moment, the aerodynamic-center position, and the induced drag of tapered wings with partial-span flaps may be calculated. The factors are given for wings of aspect ratios 6 and 10 , of taper ratios from 0.25 to 1.00, and with flaps of various length. An example is presented of the method of application of the factors. Fair agreement with experimental results is … more
Date: January 23, 1939
Creator: Pearson, Henry A. & Anderson, Raymond F.
Partner: UNT Libraries Government Documents Department
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Effective Gust Structure at Low Altitudes as Determined From the Reactions of an Airplane

Description: "Measurements of gust structure and gust intensity were made in the lower levels of the atmosphere (0 to 3,500 ft.). An Aeronca C-2 airplane was used as the measuring instrument, the gust structure being derived from the recorded motions of the airplane. Data were also obtained on wind velocities and temperatures as functions of altitude for use in attempting to correlate the gust-structure data with various meteorological quantities" (p. 263).
Date: October 19, 1939
Creator: Donely, Philip
Partner: UNT Libraries Government Documents Department
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Mechanical Properties of Flush-Riveted Joints

Description: "The strength of representative types of flush-riveted joints has been determined by testing 865 single-shearing, double-shearing, and tensile specimens representing 7 types of rivet and 18 types of joint. The results, presented in graphic form, show the stress at failure, type of failure, and d/t ratio. In general, dimpled joints were appreciably stronger than countersunk or protruding-head joints, but their strength was greatly influenced by constructional details" (p. 467).
Date: November 1939
Creator: Brueggeman, W. C. & Roop, Frederick C.
Partner: UNT Libraries Government Documents Department
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The unsteady lift of a wing of finite aspect ratio

Description: "Unsteady-lift functions for wings of finite aspect ratio have been calculated by correcting the aerodynamic inertia and the angle of attack of the infinite wing. The calculations are based on the operational method. The starting lift of the finite wing is found to be only slightly less than that of the infinite wing; whereas the final lift may be considerably less" (p. 1).
Date: June 15, 1939
Creator: Jones, Robert T.
Partner: UNT Libraries Government Documents Department
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Preliminary wind-tunnel investigation of an NACA 23012 airfoil with various arrangements of venetian-blind flaps

Description: Report presents the results of an investigation made in the NACA 7 by 10-foot wind tunnel of a large-chord NACA 23012 airfoil with several arrangements of venetian-blind flaps to determine the aerodynamic section characteristics as affected by the over-all flap chord, the chords of the slats used to form the flap, the slat spacing, the number of slats and the position of the flap with respect to the wing. Complete section data are given in the form of graphs for all the combinations tested.
Date: January 10, 1939
Creator: Wenzinger, Carl J. & Harris, Thomas A.
Partner: UNT Libraries Government Documents Department
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Longitudinal Stability and Control With Special Reference to Slipstream Effects

Description: Report presents the results of a study of data obtained in the NACA full-scale wind tunnel concerning the effects of interference and of propeller operation on longitudinal stability and control. The data include pitching moments for various power conditions for airplanes with tails removed and with tails set at various stabilizer and elevator angles. A number of surveys of the dynamic pressure and the flow direction in the region of the horizontal tail surface are also included.
Date: August 24, 1939
Creator: Katzoff, S.
Partner: UNT Libraries Government Documents Department
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Cooling on the front of an air-cooled engine cylinder in a conventional engine cowling

Description: Measurements were made of the cooling on the fronts of model cylinders in a conventional cowling for cooling in both the ground and the cruising conditions. The mechanisms of front and rear cooling are essentially different. Cooling on the rear baffled part of the cylinders continually increases with increasing fin width. For the front of the cylinder, an optimum fin width was found to exist beyond which an increase in width reduced the heat transfer. The heat transfer coefficient on the front … more
Date: April 5, 1939
Creator: Brevoort, M. J. & Joyner, U. T.
Partner: UNT Libraries Government Documents Department
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Effects of elevator nose shape, gap, balance, and tabs on the aerodynamic characteristics of a horizontal tail surface

Description: Results are presented showing the effects of gap, elevator, nose shape, balance, cut-out, and tabs on the aerodynamic characteristics of a horizontal tail surface tested in the NACA full-scale tunnel.
Date: April 27, 1939
Creator: Goett, Harry J. & Reeder, J. P.
Partner: UNT Libraries Government Documents Department
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Flame Speeds and Energy Considerations for Explosions in a Spherical Bomb

Description: "Simultaneous measurements were made of the speed of flame and the rise in pressure during explosions of mixtures of carbon monoxide, normal heptane, iso-octane, and benzene in a 10-inch spherical bomb with central ignition. From these records, fundamental properties of the explosive mixtures, which are independent of the apparatus, were computed. The transformation velocity, or speed at which flame advances into and transforms the explosive mixture, increases with both the temperature and the … more
Date: September 28, 1939
Creator: Fiock, Ernest F.; Marvin, Charles F., Jr.; Caldwell, Frank R. & Roeder, Carl H.
Partner: UNT Libraries Government Documents Department
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Correlation of Cooling Data From an Air-Cooled Cylinder and Several Multicylinder Engines

Description: "The theory of engine-cylinder cooling developed in a previous report was further substantiated by data obtained on a cylinder from a Wright R-1820-G engine. Equations are presented for the average head and barrel temperatures of this cylinder as functions of the engine and the cooling conditions. These equations are utilized to calculate the variation in cylinder temperature with altitude for level flight and climb" (p. 59).
Date: August 15, 1939
Creator: Pinkel, Benjamin & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department
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Static Thrust and Power Characteristics of Six Full-Scale Propellers

Description: "Static thrust and power measurements were made of six full-scale propellers. The propellers were mounted in front of a liquid-cooled-engine nacelle and were tested at 15 different blade angles in the range from -7 1/2 degrees to 35 degrees at 0.75r. The test rig was located outdoors and the tests were made under conditions of approximately zero wind velocity" (p. 85).
Date: January 25, 1939
Creator: Hartman, Edwin P. & Biermann, David
Partner: UNT Libraries Government Documents Department
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The effect of nacelle-propeller diameter ratio on body interference and on propeller and cooling characteristics

Description: Report presents the results of an investigation conducted in the NACA 20-foot tunnel to determine the slipstream drag, the body interference, and the cooling characteristics of nacelle-propeller diameter. Four combinations of geometrically similar propellers and nacelles, mounted on standard wing supports, were tested with values of the ratio of nacelle diameter to propeller diameter of 0.25, 0.33, and 0.44.
Date: April 17, 1939
Creator: McHugh, James G. & Derring, Eldridge H.
Partner: UNT Libraries Government Documents Department
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Effect of fuel-air ratio, inlet temperature, and exhaust pressure on detonation

Description: From Summary: "An accurate determination of the end-gas condition was attempted by applying a refined method of analysis to experimental results. The results are compared with those obtained in Technical Report no. 655. The experimental technique employed afforded excellent control over the engine variables and unusual cyclic reproducibility. This, in conjunction with the new analysis, made possible the determination of the state of the end-gas at any instant to a fair degree of precision. Resu… more
Date: November 15, 1939
Creator: Taylor, E. S.; Leary, W. A. & Diver, J. R.
Partner: UNT Libraries Government Documents Department
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Effect of exit-slot position and opening on the available cooling pressure for NACA nose-slot cowlings

Description: Report presents the results of an investigation of full-scale nose-slot cowlings conducted in the NACA 20-foot wind tunnel to furnish information on the pressure drop available for cooling. Engine conductances from 0 to 0.12 and exit-slot conductances from 0 to 0.30 were covered. Two basic nose shapes were tested to determine the effect of the radius of curvature of the nose contour; the nose shape with the smaller radius of curvature gave the higher pressure drop across the engine. The best ax… more
Date: January 18, 1939
Creator: Stickle, George W.; Naiman, Irven & Crigler, John L.
Partner: UNT Libraries Government Documents Department
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Wind-tunnel investigation of NACA 23012, 23021, and 23030 airfoils with various sizes of split flap

Description: Report presents the results of an investigation made in the NACA 7 by 10-foot wind tunnel of large-chord NACA and 23021, and 23030 airfoils with split flaps 10, 20, 30, and 40 percent of the wing chord to determine the section aerodynamic characteristics of the airfoils as affected by airfoil thickness, flap chord, and flap deflection. The complete section aerodynamic characteristics of all the combinations tested are given in the form of graphs of lift, drag, and pitching-moment coefficients, … more
Date: March 10, 1939
Creator: Wenzinger, Carl J. & Harris, Thomas A.
Partner: UNT Libraries Government Documents Department
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Airfoil section data obtained in the NACA variable-density tunnel as affected by support interference and other corrections

Description: From Introduction: "The purpose of this report is to present the corrections for application to published results from the variable-density tunnel to give more reliable values of section profile-drag coefficient for airfoils of various thickness."
Date: 1939
Creator: Jacobs, Eastman N. & Abbott, Ira H.
Partner: UNT Libraries Government Documents Department
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Surface heat-transfer coefficients of finned cylinders

Description: An investigation to determine and correlate the experimental surface heat-transfer coefficients of finned cylinders with different air-stream cooling arrangements was conducted at the Langley Memorial Aeronautical Laboratory from 1932 to 1938. The investigation covered the determination of the effect of fin width, fin space, fin thickness, and cylinder diameter on the heat transfer. Wind-tunnel tests were made in the free air stream with and without baffles and also with various devices for cre… more
Date: April 27, 1939
Creator: Ellerbrock, Herman H., Jr. & Biermann, Arnold E.
Partner: UNT Libraries Government Documents Department
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Wind-tunnel investigation of NACA 23012 airfoil with various arrangements of slotted flaps

Description: "An investigation was made in the NACA 7 by 10-foot wind tunnel of a large-chord NACA 23012 airfoil with several arrangements of 25.66 percent chord slotted flaps to determine the section aerodynamic characteristics as affected by slot shape, flap shape, flap location, and flap deflection. The flap position for maximum lift, the polars for arrangements considered favorable for take-off and climb, and the complete section aerodynamic characteristics for selected optimum arrangements were determi… more
Date: February 24, 1939
Creator: Wenzinger, Carl J. & Harris, Thomas A.
Partner: UNT Libraries Government Documents Department
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Experimental Investigation of the Momentum Method for Determining Profile Drag

Description: Report presents the results of an experimental investigation conducted in the full-scale tunnel to determine the accuracy of the Jones and the Betz equations for computing profile drag from total and static pressure surveys in the wake of wings. Surveys were made behind 6 by 8-foot airfoils of the NACA 0009, and 0018 sections at zero lift and behind the NACA 0012 at positive lifts. The surveys were made at various spanwise positions and at distances behind the airfoil ranging from 0.05c to 3.00… more
Date: 1939
Creator: Goett, Harry J.
Partner: UNT Libraries Government Documents Department
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Effect of Service Stress on Impact Resistance, X-Ray Diffraction Patterns, and Microstructure of 25S Aluminum Alloy

Description: Report presents the results of a great number of tests made to determine the effect of service stresses on the impact resistance, the x-ray diffraction patterns, and the microstructure of 25s aluminum alloy. Many of the specimens were taken from actual propeller blades and others were cut from 13/16-inch rod furnished by the Aluminum Company of America.
Date: 1939
Creator: Kies, J. A. & Quick, G. W.
Partner: UNT Libraries Government Documents Department
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