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Summarized Data of Tin Production

Description: Report presenting a statistical summary of tin production from 1801 to 1930.
Date: 1932
Creator: Umhau, John Bernard
Partner: UNT Libraries Government Documents Department
open access

Gold Quartz Veins of the Alleghany District, California

Description: From Outline of the Report: The Alleghany district, in the southern part of Sierra County, Calif., has long been famous for the high-grade gold ore of its quartz veins. The oldest rocks of the district (pp. 6-17) are of sedimentary and volcanic origin and correspond to part of the Calaveras formation as mapped in the Colfax and Downieville folios of the Geologic Atlas of the United States. These rocks are divided into five formations, of which three-the Blue Canyon, Relief, and Cape Horn format… more
Date: 1932
Creator: Ferguson, Henry G. & Gannett, Roger W.
Partner: UNT Libraries Government Documents Department
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Application of the Theory of Free Jets

Description: Based upon Kirchoff's theory of free jets the flow through different screen arrangements of flat plates, as chiefly encountered with turbines in the cavitation zone is defined. It is shown by experiments that these theoretical results are very well representative in most cases of the conditions of discharge from water in air and consequently by cavitation. In addition, the experiments reveal a picture of the discrepancies between the actual flow and the theory of discharge of air in air (of wat… more
Date: April 1932
Creator: Betz, A. & Petersohn, E.
Partner: UNT Libraries Government Documents Department
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Turbulence and Mechanism of Resistance on Spheres and Cylinders

Description: The nature of turbulent flow through pipes and around obstacles is analyzed and illustrated by photographs of turbulence on screens and straighteners. It is shown that the reversal of flow and of the resistance law on spheres is not explainable by Prandtl's turbulence in the boundary layer. The investigation of the analogous phenomena on the cylinder yields a reversal of the total field of flow.
Date: January 1932
Creator: Ahlborn, F.
Partner: UNT Libraries Government Documents Department
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Dynamic Testing of Airplane Shock-Absorbing Struts

Description: "Measurement of perpendicular impacts of a landing gear with different shock-absorbing struts against the drum testing stand. Tests were made with pneumatic shock absorbers having various degrees of damping, liquid shock absorbers, steel-spring shock absorbers and rigid struts. Falling tests and rolling tests. Maximum impact and gradual reduction of the impacts in number and time in the falling tests. Maximum impact and number of weaker impacts in rolling tests" (p. 1).
Date: January 1932
Creator: Langer, P. & Thomé, W.
Partner: UNT Libraries Government Documents Department
open access

Twelfth Rhon Soaring Contest, 1931

Description: The crew of the "Fafnir" was given an excellent opportunity for collecting first-hand data as to the usefulness of gliders in the Alps. It is necessary to recount the remarkable glider achievements ahead of the Rhon Soaring Contest, in order to understand the tension and expectation with which the Rhon contest was anticipated. A description of some of the aircraft present at the event is provided.
Date: May 1932
Creator: Georgii, Walter
Partner: UNT Libraries Government Documents Department
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German Aircraft Accident Statistics, 1930

Description: The investigation of all serious accidents, involving technical defects in the airplane or engine, is undertaken by the D.V.L. in conjunction with the imperial traffic minister and other interested parties. All accidents not clearly explained in the reports are subsequently cleared up.
Date: March 1932
Creator: Weitzmann, Ludwig
Partner: UNT Libraries Government Documents Department
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Torsional Vibration of Aircraft Engines

Description: "Exhaustive torsional-vibration investigations are required to determine the reliability of aircraft engines. A general outline of the methods used for such investigations and of the theoretical and mechanical means now available for this purpose is given, illustrated by example. True vibration diagrams are usually obtained from vibration measurements on the completed engine. Two devices for this purpose and supplementing each other, the D.V.L. torsiograph and the D.V.L. torsion recorder, are d… more
Date: May 1932
Creator: Lürenbaum, Karl
Partner: UNT Libraries Government Documents Department
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Development of Tailless and All-Wing Gliders and Airplanes

Description: Tailless airplanes are characterized by having all their control surfaces, especially the elevator, incorporated in the wings. This paper provides a discussion of the history of their development and current state of development.
Date: April 1932
Creator: Lademann, Robert W. E.
Partner: UNT Libraries Government Documents Department
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Sampling and Estimation of Ore Deposits

Description: Report issued by the Bureau of Mines over the sampling and analyses of ore deposits. Methods, problems, and results are presented and discussed. This report includes tables, and illustrations.
Date: 1932
Creator: Jackson, Charles Freeman & Knaebel, John B.
Partner: UNT Libraries Government Documents Department
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The pressure distribution over a standard and a modified Navy elliptical wing tip on a biplane in flight

Description: "This note presents the results of flight pressure distribution tests on the right upper wing panel of a Douglas M-3 airplane equipped in turn with a standard Navy elliptical tip and a tip having the same plan form but modified in its front elevation from the swept-up aspect of the standard tip to a symmetrical aspect. The results are given in such form that the load distribution for any normal-force coefficient within the usual range encountered in flight may easily be determined. The results … more
Date: October 1932
Creator: Rhode, Richard V.
Partner: UNT Libraries Government Documents Department
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Influence of Several Factors on Ignition Lag in a Compression-Ignition Engine

Description: "This investigation was made to determine the influence of fuel quality, injection advance angle, injection valve-opening pressure, inlet-air pressure, compression ratio, and engine speed on the time lag of auto-ignition of a Diesel fuel oil in a single-cylinder compression-ignition engine as obtained from an analysis of indicator diagrams. Three cam-operated fuel-injection pumps, two pumps cams, and an automatic injection valve with two different nozzles were used. Ignition lag was considered … more
Date: November 1932
Creator: Gerrish, Harold C. & Voss, Fred
Partner: UNT Libraries Government Documents Department
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The Effect of Clearance Distribution on the Performance of a Compression-Ignition Engine with a Precombustion Chamber

Description: "The clearance distribution in a precombustion chamber cylinder head was varied so that for a constant compression ratio of 13.5 the spherical auxiliary chambers contained 20, 35, 50, and 70 per cent of the total clearance volume. Each chamber was connected to the cylinder by a single circular passage, flared at both ends, and of a cross-sectional area proportional to the chamber volume, thereby giving the same calculated air-flow velocity through each passage. Results of engine-performance tes… more
Date: November 1932
Creator: Moore, C. S. & Collins, J. H., Jr.
Partner: UNT Libraries Government Documents Department
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Compression-ignition engine tests of several fuels

Description: "The tests reported in this paper were made to devise simple engine tests which would rate fuels as to their comparative value and their suitability for the operating conditions of the individual engine on which the tests are made. Three commercial fuels were used in two test engines having combustion chambers with and without effective air flow. Strictly comparative performance tests gave almost identical results for the three fuels. Analysis of indicator cards allowed a differentiation betwee… more
Date: May 1932
Creator: Spanogle, J. A.
Partner: UNT Libraries Government Documents Department
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Wind-tunnel tests of the Fowler variable-area wing

Description: The lift, drag, and center of pressure characteristics of a model of the Fowler variable-area wing were measured in the NACA 7 by 10 foot wind tunnel. The Fowler wing consists of a combination of a main wing and an extension surface, also of airfoil section. The extension surface can be entirely retracted within the lower rear portion of the main wing or it can be moved to the rear and downward. The tests were made with the nose of the extension airfoil in various positions near the trailing ed… more
Date: May 1932
Creator: Weick, Fred E. & Platt, Robert C.
Partner: UNT Libraries Government Documents Department
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The effect of connecting-passage diameter on the performance of a compression-ignition engine with a precombustion chamber

Description: Results of motoring tests are presented showing the effect of passage diameter on chamber and cylinder compression pressures, maximum pressure differences, and f.m.e.p. over a speed range from 300 to 1,750 r.p.m. Results of engine performance tests are presented which show the effect of passage diameter on m.e.p., explosion pressures, specific fuel consumption, and rates of pressure rise for a range of engine speeds from 500 to 1,500 r.p.m. The cylinder compression pressure, the maximum pressur… more
Date: November 1932
Creator: Moore, C. S. & Collins, J. H., Jr.
Partner: UNT Libraries Government Documents Department
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The Effect of Propellers and Nacelles on the Landing Speeds of Tractor Monoplanes

Description: "This paper reports wind-tunnel tests giving the lift coefficients of large-scale wing-nacelle combinations both with and without the propeller. The tests were made to show the effect of nacelles, and idling and stopped propellers on the landing speeds of tractor monoplanes. Four types of nacelles with various cowlings were used in numerous positions with respect to both a Clark Y and a thick airfoil. The effect of both the idling and stopped propeller on lift, and consequently on landing speed… more
Date: May 1932
Creator: Windler, Ray
Partner: UNT Libraries Government Documents Department
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The Nature of Air Flow About the Tail of an Airplane in a Spin

Description: "Air flow about the fuselage and empennage during a high-angle-of-attack spin was made visible in flight by means of titanium-tetrachloride smoke and was photographed with a motion-picture camera. The angular relation of the direction of the smoke streamer to the airplane axes was computed and compared with the angular direction of the motion in space derived from instrument measurement of the spin of the airplane for a nearly identical mass distribution. The results showed that the fin and upp… more
Date: May 1932
Creator: Scudder, N. F. & Miller, M. P.
Partner: UNT Libraries Government Documents Department
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The pressure distribution over a long elliptical wing tip on a biplane in flight

Description: This note presents the results of flight pressure-distribution tests on the right upper wing panel of a Douglas M-3 airplane equipped with an elliptical tip of length equal to the wing chord. The results are given in such form that the load distribution for any normal-force coefficient within the usual range encountered in flight may easily be determined.
Date: December 1932
Creator: Rhode, Richard V.
Partner: UNT Libraries Government Documents Department
open access

The Aerodynamic Characteristics of a Model Wing Having a Split Flap Deflected Downward and Moved to the Rear

Description: "Tests were made on a model wing with three different sized split trailing-edged flaps, in the NACA 7 by 10 foot wind tunnel. The flaps were formed of the lower rear portion of the wing and were rotated downward about axes at their front edges. The lift, drag, and center of pressure were measured with the axis in its original position and also with it moved back in even steps to the trailing edge of the main wing, giving in effect an increase in area. The split flaps when deflected about their … more
Date: May 1932
Creator: Weick, Fred E. & Harris, Thomas A.
Partner: UNT Libraries Government Documents Department
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Effect of Length of Handley Page Tip Slots on the Lateral-Stability Factor, Damping in Roll

Description: "Tests have been made in the NACA 7 by 10 foot wind tunnel on a Clark Y wing model equipped with various lengths of Handley Page slots extending inward from the wing tips. The slot lengths tested ranged from 20 to 100 per cent of the semi span. The effect of slot lengths on damping in roll was determined by means of both free-autorotation and forced-rotation test. In addition, the maximum lift coefficient was found with each slot length. The optimum length of slot for satisfactory damping in ro… more
Date: July 1932
Creator: Weick, Fred E. & Wenzinger, Carl J.
Partner: UNT Libraries Government Documents Department
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Preliminary photomicrographic studies of fuel sprays

Description: Photomicrographs were taken of fuel sprays injected into air at various densities for the purpose of studying the spray structure and the stages in the atomization of the fuel. The photomicrographs were taken at magnifying powers of 2.5, 3.25, and 10, using a spark discharge of very short duration for illumination. The results indicate that the theory advanced by Dr. R. A. Castleman, Jr., on the atomization of fuel in carburetors may also be applied to the atomization of fuel sprays of the soli… more
Date: July 1932
Creator: Lee, Dana W. & Spencer, Robert C.
Partner: UNT Libraries Government Documents Department
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Methods of Visually Determining the Air Flow Around Airplanes

Description: "This report describes methods used by the National Advisory Committee for Aeronautics to study visually the air flow around airplanes. The use of streamers, oil and exhaust gas streaks, lampblack and kerosene, powdered materials, and kerosene smoke is briefly described. The generation and distribution of smoke from candles and from titanium tetrachloride are described in greater detail because they appear most advantageous for general application. Examples are included showing results of the v… more
Date: July 1932
Creator: Gough, Melvin N. & Johnson, Ernest
Partner: UNT Libraries Government Documents Department
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