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Revision of the Mice of the American Genus Peromyscus

Description: From letter of transmittal: "The work consists of a systematic study of all the members of the genus, and includes keys for the identification of the various forms, together with the necessary illustrations, and maps showing the geographic distribution of the species."
Date: April 17, 1909
Creator: Osgood, Wilfred H.
Partner: UNT Libraries Government Documents Department
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A Biological Survey of Colorado

Description: From introduction: "Report based chiefly on the field work prosecuted during 1905, 1906, 1907, and 1909. It is primarily a characterization of the several major distribution areas or life zones."
Date: August 17, 1911
Creator: Cary, Merritt
Partner: UNT Libraries Government Documents Department
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Relative Worth of Improvements of Fabrics

Description: Report presents an equation that connects all the major qualities of a fabric, from which the fabric may be rigidly designed with respect to maximum ultimate economy.
Date: August 17, 1915
Creator: Goodyear Tire And Rubber Company
Partner: UNT Libraries Government Documents Department
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Cooperative Measurements of Radio Fading in 1925

Description: Scientific paper issued by the Bureau of Standards over studies conducted on radio fading. As stated in the abstract, "the series of measurements on fading were devoted to studies of fading effects during the sunset period, effects during the solar eclipse of January 24, the fading variations throughout a 24-hour day, and the effects of high transmitting power on fading" (p. 419). This paper includes tables, maps, illustrations, and photographs.
Date: August 17, 1927
Creator: Dellinger, J. H.; Jolliffe, C. B. & Parkinson, T.
Partner: UNT Libraries Government Documents Department
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Drag and Cooling With Various Forms of Cowling for A "Whirlwind" Radial Air-Cooled Engine - 2

Description: "This report gives the results of the second portion of an investigation in the twenty-foot Propeller Research Tunnel of the National Advisory Committee for Aeronautics, on the cowling and cooling of a "Whirlwind" J-5 radial air-cooled engine. The first portion pertains to tests with a cabin fuselage. This report covers tests with several forms of cowling, including conventional types, individual fairings behind the cylinders, individual hoods over the over the cylinders, and the new N. A. C. A. complete cowling, all on an open cockpit fuselage. Drag tests were also made with a conventional engine nacelle, and with a nacelle having the new complete cowling" (p. 191).
Date: December 17, 1928
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department
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Flow and Force Equations for a Body Revolving in a Fluid

Description: Part I gives a general method for finding the steady-flow velocity relative to a body in plane curvilinear motion, whence the pressure is found by Bernoulli's energy principle. Integration of the pressure supplies basic formulas for the zonal forces and moments on the revolving body. Part II, applying this steady-flow method, finds the velocity and pressure at all points of the flow inside and outside an ellipsoid and some of its limiting forms, and graphs those quantities for the latter forms. Part III finds the pressure, and thence the zonal force and moment, on hulls in plane curvilinear flight. Part IV derives general equations for the resultant fluid forces and moments on trisymmetrical bodies moving through a perfect fluid, and in some cases compares the moment values with those found for bodies moving in air. Part V furnishes ready formulas for potential coefficients and inertia coefficients for an ellipsoid and its limiting forms. Thence are derived tables giving numerical values of those coefficients for a comprehensive range of shapes.
Date: December 17, 1928
Creator: Zahm, A. F.
Partner: UNT Libraries Government Documents Department
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Tables for pressure of air on coming to rest from various speeds

Description: From Summary: "In Technical Report no. 247 of the National Advisory Committee for Aeronautics theoretical formulas are given from which was computed a table for the pressure of air on coming to rest from various speeds, such as those of aircraft and propeller blades. In that report, the table gave incompressible and adiabatic stop pressures of air for even-speed intervals in miles per hour and for some even-speed intervals in knots per hour. Table II of the present report extends the above-mentioned table by including the stop pressures of air for even-speed intervals in miles per hour, feet per-second, knots per hour, kilometers per hour, and meters per second."
Date: December 17, 1928
Creator: Zahm, A. F. & Louden, F. A.
Partner: UNT Libraries Government Documents Department
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Full-scale turning characteristics of the U.S.S. Los Angeles

Description: This paper present a description of the method employed and results obtained in full-scale turning trials on the rigid airship U. S. S. "Los Angeles". The results of this investigation are not sufficiently comprehensive to permit definite conclusions as to the variation of turning characteristics with changes in speed and rudder angle. They indicate however, that the turning radius compares favorably with that for other large airships, that the radius is independent of the speed, that the position of the point of zero yaw is nearly independent of the rudder angle and air speed, and that a theoretical relation between radius and angle of yaw in a turn gives a close approximation to actuality.
Date: April 17, 1929
Creator: Thompson, F. L.
Partner: UNT Libraries Government Documents Department
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Relation of Hydrogen and Methane to Carbon Monoxide in Exhaust Gases From Internal-Combustion Engines

Description: The relation of hydrogen and methane to carbon monoxide in the exhaust gases from internal-combustion engines operating on standard-grade aviation gasoline, fighting-grade aviation gasoline, hydrogenated safety fuel, laboratory diesel fuel, and auto diesel fuel was determined by analysis of the exhaust gases. Two liquid-cooled single-cylinder spark-ignition, one 9-cylinder radial air-cooled spark-ignition, and two liquid-cooled single-cylinder compression-ignition engines were used.
Date: August 17, 1933
Creator: Gerrish, Harold C. & Tessmann, Arthur M.
Partner: UNT Libraries Government Documents Department
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An Aerodynamic Analysis of the Autogiro Rotor With a Comparison Between Calculated and Experimental Results

Description: This report presents an extension of the autogiro theory of Glauert and Lock in which the influence of a pitch varying with the blade radius is evaluated and methods of approximating the effect of blade tip losses and the influence of reversed velocities on the retreating blades are developed. A comparison of calculated and experimental results showed that most of the rotor characteristics could be calculated with reasonable accuracy, and that the type of induced flow assumed has a secondary effect upon the net rotor forces, although the flapping motion is influenced appreciably. An approximate evaluation of the effect of parasite drag on the rotor blades established the importance of including this factor in the analysis.
Date: January 17, 1934
Creator: Wheatley, John B.
Partner: UNT Libraries Government Documents Department
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Tests of nacelle-propeller combinations in various positions with reference to wings 4: thick wing - various radial-engine cowlings - tandem propellers

Description: This report is the fourth of a series giving the results obtained from wind tunnel tests to determine the interference lift and drag and propulsive efficiency of wing-nacelle-propeller combinations. Previous reports give the results of tests with tractor propellers with various forms of nacelles and engine cowlings. This report gives the results of tests of tandem arrangements of engines and propellers in 11 positions with reference to a thick wing.
Date: January 17, 1934
Creator: McHugh, James G.
Partner: UNT Libraries Government Documents Department
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Noise From Two-Blade Propellers

Description: "The two-blade propeller, one of the most powerful sources of sound known, has been studied with the view of obtaining fundamental information concerning the noise emission. In order to eliminate engine noise, the propeller was mounted on an electric motor. A microphone was used to pick up the sound whose characteristics were studied electrically. The distribution of noise throughout the frequency range, as well as the spatial distribution about the propeller, was studied. The results are given in the form of polar diagrams. An appendix of common acoustical terms is included" (p. 359).
Date: January 17, 1935
Creator: Stowell, E. Z. & Deming, A. F.
Partner: UNT Libraries Government Documents Department
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A Theory for Primary Failure of Straight Centrally Loaded Columns

Description: "A theory of primary failure of straight centrally loaded columns is presented. It is assumed that the column cross section and the load are constant throughout the length. Primary failure is defined as any type of failure in which the cross sections are translated, rotated, or translated and rotated but not distorted in their own planes" (p. 141).
Date: August 17, 1936
Creator: Lundquist, Eugene E. & Fligg, Claude M.
Partner: UNT Libraries Government Documents Department
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An Analysis of Lateral Stability in Power-Off Flight With Charts for Use in Design

Description: "The aerodynamic and mass factors governing lateral stability are discussed and formulas are given for their estimation. Relatively simple relationships between the governing factors and the resulting stability characteristics are presented. A series of charts is included with which approximate stability characteristics may be rapidly estimated" (p. 1).
Date: November 17, 1936
Creator: Zimmerman, Charles H.
Partner: UNT Libraries Government Documents Department
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The experimental and calculated characteristics of 22 tapered wings

Description: From Summary: "The experimental and calculated aerodynamic characteristics of 22 tapered wings are compared, using tests made in the variable-density wind tunnel. The wings had aspect ratios from 6 to 12 and taper ratios from 1:6:1 and 5:1. The compared characteristics are the pitching moment, the aerodynamic-center position, the lift-curve slope, the maximum lift coefficient, and the curves of drag. The method of obtaining the calculated values is based on the use of wing theory and experimentally determined airfoil section data. In general, the experimental and calculated characteristics are in sufficiently good agreement that the method may be applied to many problems of airplane design."
Date: November 17, 1937
Creator: Anderson, Raymond F.
Partner: UNT Libraries Government Documents Department
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Pressure distribution over an NACA 23012 airfoil with a slotted and a plain flap

Description: Report presents the results of pressure-distribution of an NACA 23012 airfoil equipped with a slotted flap and with a plain flap conducted in the 7 by 10-foot wind tunnel. A test installation was used in which the 7-foot-span airfoil was mounted vertically between the upper and lower sides of the closed test section so that two-dimensional flow was approximated. The pressures were measured on the upper and lower surfaces at one chord section both on the main airfoil and on the flaps for several different flap deflections and at several angles of attack. The data are presented in the form of pressure-distribution diagrams and as graphs of calculated section coefficients for the airfoil-and-flap combinations and also for the flaps alone. The results are useful for application to rib and flap structural design; in addition, the plain-flap data furnish considerable information applicable to the structural design of plain ailerons.
Date: March 17, 1938
Creator: Wenzinger, Carl J. & Delano, James B.
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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A simplified theoretical method of determining the characteristics of a lifting rotor in forward flight

Description: Theoretical derived expressions for the flapping, the thrust, the torque, and the profile drag-lift ratio of nonfeathering rotor with hinged, rectangular, linearly twisted blades are given as simple functions of the inflow velocity and the blade pitch. Representative values of the coefficients of each of the terms in these expressions are tabulated for a series of specified values of the tip-speed ratio. Analysis indicates that the tabulated values can be used to calculate, with reasonable accuracy, the characteristics of any rotor of conventional design.
Date: March 17, 1941
Creator: Bailey, F. J., Jr.
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of an NACA 23012 Airfoil With 30 Percent-Chord Venetian-Blind Flaps

Description: Report presents the results of an investigation made in the NACA 7 by 10-foot wind tunnel of a NACA 23012 airfoil with 30-percent-chord venetian-blind flaps having one, two, three, and four slats of Clark y section. The three-slat arrangements was aerodynamically the best of those tested but showed practically no improvement over the comparable arrangement used in the preliminary tests published in NACA Technical Report No. 689. The multiple-slat flaps gave slightly higher lift coefficients than the one-slat (Fowler) flap but gave considerably greater pitching-moment coefficients.
Date: September 17, 1941
Creator: Rogallo, F. M. & Spano, Bartholomew S.
Partner: UNT Libraries Government Documents Department
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Production of Uranium Metal

Description: Experiments were carried out for the purpose of increasing production, efficiency, and purity of uranium metal. The electrolytic method as described by Driggs and Lilliendahl for the preparation of uranium metal was followed with but little deviation. The yield of metal at the very best was only 50%. The metal powder produced, at times, was very pyrophoric. Methods were found whereby the metal, at least in part, can be made from the oxides with an average yield of about 90%. The small amounts of sludge and slag accumulated in this modified process can readily be re-used in the electrolysis pot and, therefore, an overall yield of 96% can be obtained. Information accumulated from these experiments has been compiled in such a manner as to be readily available for factory use, for patent purposes and for future publication.
Date: February 17, 1943
Creator: Nagy, R.
Partner: UNT Libraries Government Documents Department
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NACA Investigation of a Jet-Propulsion System Applicable to Flight

Description: "Following a brief history of the NACA investigation of jet propulsion, a discussion is given of the general investigation and analysis leading to the construction of the jet-propulsion ground-test mock-up. The results of burning experiments and of test measurements designed to allow quantitative flight performance predictions of the system are presented and correlated with calculations. These calculations are then used to determine the performance of the system on the ground and in the air at various speeds and altitudes under various burning conditions. The application of the system to an experimental airplane is described and some performance predictions for this airplane are made" (p. 1).
Date: September 17, 1943
Creator: Ellis, Macon C., Jr. & Brown, Clinton E.
Partner: UNT Libraries Government Documents Department
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Concentration of C-2 Slag

Description: The bomb reaction slag produced at the ElectroMetallurgical X metal plant is at present divided into rich C-1 slag and lean C-2 slag by merely screening through a 4 mesh wire screen, the "on 4 mesh" material becomes the C-1 slag and the "thru 4 mesh" material becomes the C-2 slag. In the experiments covered by this report it was found that the concentration of the lean C-2 slag could be facilitated by the use of a 20 mesh screen for the slang separation in place of the 4 mesh screen, as the 20 mesh screen removed troublesome, small, hard lumps which passed the 4 mesh screen. Furthermore, it was found that the additional small lumps removed by the 20 mesh screen were just as rich in X metal as the larger lumps which make up the bulk of C-1 slag.
Date: February 17, 1944
Creator: Thomas, W.G.
Partner: UNT Libraries Government Documents Department
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Capture of Fast Neutrons by Pb208

Description: From abstract: "Comparison of the activity produced by fast neutrons on lead with other activations corroborates the assignment of the 3.2 hr. activity as Pb209, and the assignment of the reaction as capture of fast neutrons. Two different measurements show that the neutrons captured have energies greater than 100 KEV. This average capture cross section for primary neutrons from 7.5 MEV deuterons on a thick target of beryllium is measured as 10[^]-27 ca[^]2."
Date: April 17, 1944
Creator: Levinger, Joseph S., 1921-; Compton, A. H.; Allison, Samuel King, 1900-1965; Watson, W. W. & Snell, A. H.
Partner: UNT Libraries Government Documents Department
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