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Revision of the Wood Rats of the Genus Neotoma

Description: From introduction: "Result of a study of the wood rats in the collection of the Biological Survey, numbering over 3,000 specimens, including topotypes of most of the species."
Date: October 19, 1910
Creator: Goldman, Edward A.
Partner: UNT Libraries Government Documents Department
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Toluol Recovery

Description: Technical paper issued by the Bureau of Standards over toluol-recovery, known as light oil. The methods used in the toluol-recovery are presented and discussed. This paper includes tables, and illustrations.
Date: December 19, 1918
Creator: McBride, R. S.; Reinicker, C. E. & Dunkley, W. A.
Partner: UNT Libraries Government Documents Department
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The Ultra-Violet and Visible Transmission of Various Colored Glasses

Description: Technical paper issued by the Bureau of Standards over studies conducted on transmissions of ultra-violet energy through different colored glasses. As stated in the introduction, "in the present paper are given the transmissions for the visible and ultra-violet of a large number of glasses, mostly colored, which are not used primarily for eye protection, but which are useful for various other purposes" (p. 3). This paper includes illustrations, and photographs.
Date: March 19, 1920
Creator: Gibson, K. S.; Tyndall, E. P. T. & McNicholas, H. J.
Partner: UNT Libraries Government Documents Department
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Rolling Moments Due to Rolling and Yaw for Four Wing Models in Rotation

Description: "This report presents the results of a series of autorotation and torque tests on four different rotating wing systems at various rates of roll and at several angles of yaw. The investigation covered an angle of attack range up to 90 degrees and angles of yaw of 0 degree, 5 degrees, 10 degrees, and 20 degrees. The tests were made in a 5-foot, closed-throat atmospheric wind tunnel. The object of the tests was primarily to determine the effects of various angles of yaw on the rolling moments of the rotating wings up to large angles of attack" (p. 301).
Date: August 19, 1930
Creator: Knight, Montgomery & Wenzinger, Carl J.
Partner: UNT Libraries Government Documents Department
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Some approximate equations for the standard atmosphere

Description: This report contains the derivation of a series of simple approximate equations for density ratios and for the pressure ratio in the standard atmosphere. The accuracy of the various equations is discussed and the limits of applications are given. Several of these equations are in excellent agreement with the standard values.
Date: September 19, 1930
Creator: Diehl, Walter S.
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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Maneuverability investigation of an O3U-1 observation airplane

Description: From Summary: "This report presents the results of maneuverability tests of an O3U-1 observation airplane. This investigation is the third in a series of similar investigations requested by the Bureau of Aeronautics (Navy) for the purpose of comparing the maneuverability of different airplane types and to provide quantitative data for use in establishing a criterion or method for rating the maneuverability of an airplane. The two former investigations were conducted with the fighter types designated F6C-3 and F6C-4 and have been reported previously. Measurement of the air speed, the angular velocity, the linear acceleration, and positions of the controls were made during abrupt single-control maneuvers with three stop positions for each control, during steady horizontal turns for the determination of minimum radius, and during 180 degree turns by various methods."
Date: January 19, 1933
Creator: Thompson, F. L. & Kirschbaum, H. W.
Partner: UNT Libraries Government Documents Department
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A Flight Investigation of the Lateral Control Characteristics of Short Wide Ailerons and Various Spoilers With Different Amounts of Wing Dihedral

Description: This report presents the results of flight tests made to determine the lateral control characteristics of short wide ailerons and spoilers, as a consequence of the promise shown in wind-tunnel tests by these devices as means of obtaining lateral control, particularly at angles of attack above the stall. Several forms of spoilers, front-hinge, rear-hinge, plain retractable, and saw-tooth retractable were tested alone and in combination with the ailerons. The tests were made with several different amounts of wing dihedral so that the effect of the yawing moments of the different lateral control combinations, which varied from large negative to large positive values, could be evaluated. In conjunction with the tests, observations were made to throw some light on the feasibility of operating the airplane with two controls instead of the present three.
Date: May 19, 1934
Creator: Weick, Fred E.; Soulé, Hartley A. & Gough, Melvin N.
Partner: UNT Libraries Government Documents Department
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Tank tests of NACA model 40 series of hulls for small flying boats and amphibians

Description: From Summary: "The NACA model 40 series of flying-boat hull models consists of 2 forebodies and 3 afterbodies combined to provide several forms suitable for use in small marine aircraft. One forebody is the usual form with hollow bow sections and the other has a bottom surface that is completely developable from bow to step. The afterbodies include a short pointed afterbody with an extension for the tail surfaces, a long afterbody similar to that of a seaplane float but long enough to carry the tail surfaces, and a third obtained by fitting a second step in the latter afterbody."
Date: June 19, 1935
Creator: Parkinson, John B. & Dawson, John R.
Partner: UNT Libraries Government Documents Department
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A simplified application of the method of operators to the calculation of disturbed motions of an airplane

Description: "A simplified treatment of the application of Heaviside's operational methods to problems of airplane dynamics is given. Certain graphical methods and logarithmic formulas that lessen the amount of computation involved are explained. The problem representing a gust disturbance or control manipulation is taken up and it is pointed out that in certain cases arbitrary control manipulations may be dealt with as though they imposed specific constraints on the airplane, thus avoiding the necessity of any integration" (p. 313).
Date: February 19, 1936
Creator: Jones, Robert T.
Partner: UNT Libraries Government Documents Department
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Effect of nozzle design on fuel spray and flame formation in a high-speed compression-ignition engine

Description: "Fuel was injected from different type of injection nozzles into the combustion chamber of the NACA combustion apparatus, operated as a compression-ignition engine. High speed motion pictures were taken of the fuel sprays and combustion. Single-orifice nozzles of 0.008, 0.020, and 0.040 inch diameter, and multiorifice nozzles having 2, 6, and 16 orifices were tested. Nozzles having impinging jets and slit orifices were also included" (p. 327).
Date: March 19, 1936
Creator: Rothrock, A. M. & Waldron, C. D.
Partner: UNT Libraries Government Documents Department
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The Rolling Friction of Several Airplane Wheels and Tires and the Effect of Rolling Friction on Take-Off

Description: This report presents the results of tests made to determine the rolling friction of airplane wheels and tires under various conditions of wheel loading, tire inflation pressure, and ground surface. The effect of wheel-bearing type was also investigated. Six pairs of wheels and tires were tested including two sizes of each of the types designated as standard (high pressure), low pressure, and extra low pressure. The results of calculations intended to show the effect of variations in rolling friction on take-off are also presented.
Date: September 19, 1936
Creator: Wetmore, J. W.
Partner: UNT Libraries Government Documents Department
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Compressible Flow About Symmetrical Joukowski Profiles

Description: "The method of Poggi is employed for the determination of the effects of compressibility upon the flow past an obstacle. A general expression for the velocity increment due to compressibility is obtained. The general result holds whatever the shape of the obstacle; but, in order to obtain the complete solution, it is necessary to know a certain Fourier expansion of the square of the velocity of flow past the obstacle. An application is made to the case flow of a symmetrical Joukowski profile with a sharp trailing edge, fixed in a stream of an arbitrary angle of attack and with the circulation determined by the Kutta condition" (p. 197).
Date: November 19, 1937
Creator: Kaplan, Carl
Partner: UNT Libraries Government Documents Department
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Theoretical stability and control characteristics of wings with various amounts of taper and twist

Description: From Summary: "Stability derivatives have been computed for twisted wings of different plan forms that include variations in both the wing taper and the aspect ratio. Taper ratios of 1.0, 0,50, and 0.25 are considered for each of three aspect ratios: 6, 10, and 16. The specific derivatives for which results are given are the rolling-moment and the yawing-moment derivatives with respect to (a) rolling velocity, (b) yawing velocity, and (c) angle of sideslip. These results are given in such a form that the effect of any initial symmetrical wing twist (such as may be produced by flaps) on the derivatives may easily be taken into account."
Date: April 19, 1938
Creator: Pearson, Henry A. & Jones, Robert T.
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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Propeller analysis from experimental data

Description: The operation of the propeller is analyzed by the use of the distribution of forces along the radius, combined with theoretical equations. The data were obtained in the NACA 20-foot wind tunnel on a 4-foot-diameter, two-blade propeller, operating in front of four body shapes, ranging from a small shaft to support the propeller to conventional NACA cowling. A method of estimating the axial and the rotational energy in the wake as a fractional part of the propeller power is given. A knowledge of the total thrust and torque is necessary for the estimation.
Date: July 19, 1940
Creator: Stickle, George W. & Crigler, John L.
Partner: UNT Libraries Government Documents Department
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Flight Measurements of the Effects of a Wing Leading-Edge Slot and Other Modifications on the Stability, Maximum Lift, and High Speed of an Observation Airplane

Description: Report presenting stability, maximum lift, and high-speed tests of an observation airplane fitted with Maxwell leading-edge slots. The static and dynamic longitudinal and lateral stability was generally satisfactory and not affected much by the slots.
Date: January 19, 1943
Creator: Turner, William N. & Adams, Betty
Partner: UNT Libraries Government Documents Department
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Critical amounts of uranium compounds

Description: No Description Available.
Date: March 19, 1943
Creator: Konopinski, E.; Metropolis, N.; Teller, E. & Woods, L.
Partner: UNT Libraries Government Documents Department
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Time Variation of Percent Distribution of Fission Activity in Bombarded Uranyl Nitrate

Description: "In this report are presented three figures which show how the relative activities (expressed as percentages of total activity) of the individual fission elements (produced by neutron bombardment of uranyl nitrate) vary with cooling time."
Date: May 19, 1943
Creator: Brady, E. L. & Coryell, Charles D.
Partner: UNT Libraries Government Documents Department
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Memorandum on Uranium Ore Processing

Description: The following memorandum discusses experiments and methods to recover uranium from Colorado-Utah sandstone and leaving the vanadium in the tails, improving filterability.
Date: November 19, 1943
Creator: Brimm, E. O. & Gailey, A. J.
Partner: UNT Libraries Government Documents Department
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On the plane potential flow past a lattice of arbitrary airfoils

Description: The two-dimensional, incompressible potential flow past a lattice of airfoils of arbitrary shape is investigated theoretically. The problem is treated by usual methods of conformal mapping in several stages, one stage corresponding to the mapping of the framework of the arbitrary line lattice and another significant stage corresponding to the Theodorsen method for the mapping of the arbitrary single wing profile into a circle. A particular feature in the theoretical treatment is the special handling of the regions at an infinite distance in front of and behind the lattice. Expressions are given for evaluation of the velocity and pressure distribution at the airfoil boundary. An illustrative numerical example is included.
Date: November 19, 1943
Creator: Garrick, I. E.
Partner: UNT Libraries Government Documents Department
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A Theoretical Investigation of the Rolling Oscillations of an Airplane With Ailerons Free

Description: "An analysis is made of the stability of an airplane with ailerons free, with particular attention to the motions when the ailerons have a tendency to float against the wind. The present analysis supersedes the aileron investigation contained in NACA Technical Report no. 709. The equations of motion are first written to include yawing and sideslipping, and it is demonstrated that the principal effects of freeing the ailerons can be determined without regard to these motions" (p. 255).
Date: November 19, 1943
Creator: Cohen, Doris
Partner: UNT Libraries Government Documents Department
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The Effects of a Highly Cambered Low-Drag Wing and of Auxiliary Flaps on the High-Speed Aerodynamic Characteristics of a Twin-Engine Pursuit Airplane Model

Description: Results are presented for tests of two wings, an NACA 230-series wing and a highly-cambered NACA 66-series wing on a twin-engine pursuit airplane. Auxiliary control flaps were tested in combinations with each wing. Data showing comparison of high-speed aerodynamic characteristics of the model when equipped with each wing, the effect of the auxiliary control flaps on aerodynamic characteristics, and elevator effectiveness for the model with the 66-series wing are presented. High-speed aerodynamic characteristics of the model were improved with the 66-series wing.
Date: February 19, 1944
Creator: Ganzer, Victor M.
Partner: UNT Libraries Government Documents Department
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