Technical Report Archive & Image Library (TRAIL) - 172 Matching Results

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Copper Mining in North America

Description: From introduction: "In this paper are assembled and summarized many subjects relating to the copper industry in North America. Production of mines and districts, history of the industry in North America. Production of mines and districts, history of the industry, geology, of the principal deposits, and mining methods and costs are discussed."
Date: 1938
Creator: Gardner, E. D.; Johnson, C. H. & Butler, B. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Crushing and Grinding

Description: From introduction: "The purpose of this bulletin is to discuss the theory of crushing and grinding in relation to present-day discoveries and developments and to consider the various mechanical appliances from a theoretical basis."
Date: 1938
Creator: Gross, John
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mineral Industries Survey of the United States: California, Calaveras County, Mother Lode District (South). Mines of the Southern Mother Lode Region. Part 1 -- Calaveras County

Description: From Introduction: "The present paper discusses regional resources, chiefly of gold, the existence of which has long been demonstrated by substantial production but which are so nearly marginal in value that their mining has been protracted and will probably continue indefinitely for many decades."
Date: 1938
Creator: Julihn, C. E. & Horton, F. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Quarry Accidents in the United States During the Calendar Year 1936

Description: Report published by the U.S. Bureau of Mines which is a compilation of accidents in quarries located in the United States with data regarding the number and kinds of accidents as well as information about the mining operations (e.g., number of men employed, kinds of quarries, amount of work performed, etc.).
Date: 1938
Creator: Adams, William W. & Wrenn, Virginia E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of Certain Properties of Oil Shale and Shale Oil

Description: From Scope of Report: "In connection with the study of the oil-shale resources of the United States, the Bureau of Mines has carried on not only extensive laboratory and field investigations but has constructed and operated an experimental shale-oil plant in Colorado. This report is based entirely upon subject matter that appeared in published and unpublished manuscripts of the Bureau of Mines."
Date: 1938
Creator: Guthrie, Boyd
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coal-Mine Accidents in the United States, 1935

Description: Report compiled by the U.S. Bureau of Mines including statistics on fatal and non-fatal accidents in coal mines located in the United States as well as data regarding the various operations (e.g., number of miners employed and average production). The information is organized into tables for comparison and the text draws some overall conclusions in the summary.
Date: 1938
Creator: Adams, W. W.; Geyer, L. E. & Parry, M. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Metal-Mine Accidents in the United States During the Calendar Year 1935

Description: Report issued by the U.S. Bureau of Mines covering accidents that happened in metal mines located in the United States including statistics for injuries, fatalities, kinds and causes of accidents, and operational data, such as number of mine workers and shifts worked.
Date: 1938
Creator: Adams, W. W. & Kolhos, M. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Carbonizing Properties of West Virginia Coals and Blends of Coals From the Alma, Cedar Grove, Dorothy Powellton A, Eagle, Pocahontas and Beckley Beds

Description: From Introduction: "The composition and carbonizing properties of 33 coals previously tested have been given in technical papers of the Bureau of Mines and in short reports published for the most part in the Proceedings of the American Gas Association. A complete list of publications on the work previous to 1937 is appended to this report. The present report gives the composition and carbonizing properties of seven additional coals from West Virginia. The data include results of blending test i… more
Date: 1938
Creator: Fieldner, A. C.; Davis, J. D.; Selvig, W. A.; Thiessen, R.; Reynolds, D. A.; Holmes, C. R. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Procedure in Sealing and Unsealing Mine Fires and in Recovery Operations Following Mine Explosions

Description: Circular describing organization, equipment, and materials, and procedure in fighting, sealing, and unsealing mine fires and in recovery operations at the time of or after fires or explosions.
Date: 1938
Creator: Forbes, John J. V. (John Joseph Vincent), 1885-1975. & Grove, G. W. (George Wallace), 1887-
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of spark-timing regularity on the knock of engine performance

Description: Tests on a high-speed single-cylinder engine are described. The regularity of the spark timing was varied by driving the timer from different engine shafts. A simple and reasonably accurate method of determining the spark timing is described. The results show that irregular spark timing may cause large errors in tests of the knocking properties of fuels. For the engine tested, it was found that a change of one crankshaft degree in spark restart was equivalent to an 0.85 inch Hg change in allowa… more
Date: May 1938
Creator: Biermann, Arnold E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tables of Stiffness and Carry-Over Factor for Structural Members Under Axial Load

Description: "Tables of stiffness and carry-over factor are presented for members in which the cross section and axial load do not vary along the length of the member. These tables are of use in solving problems in the stability of structural members under axial load as well as in application of the Cross method of moment distribution when the effects of axial load in the members are considered. The interval between successive values of the argument is small enough to make interpolation unnecessary in engin… more
Date: June 1938
Creator: Lundquist, Eugene E. & Kroll, W. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrodynamic and Aerodynamic Tests of Four Models of Outboard Floats: (N.A.C.A. Models 51-A, 51-B, 51-C, and 51-D)

Description: Four models of outboard floats (N.A.C.A. models 51-A, 51-B, 51-C, and 51-D) were tested in the N.A.C.A. tank to determine their hydrodynamic characteristics and in the 20-foot wind tunnel to determine their aerodynamic drag. The results of the tests, together with comparisons of them, are presented in the form of charts. From the comparisons, the order of merit of the models is estimated for each factor considered. The best compromise between the various factors seems to be given by model 51-D.… more
Date: December 1938
Creator: Dawson, John R. & Hartman, Edwin P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A flight investigation of the reduction of aileron operating force by means of fixed tabs and differential linkage, with notes on linkage design

Description: Flight tests were made to demonstrate the particularity of employing fixed tabs in conjunction with a suitably designed differential linkage to reduce the force required to operate ailerons. The tests showed the system to be practicable with tabs of the inset type. The relative ineffectiveness of attached tabs for changing the aileron floating angle rendered them unsuitable. Experience gained in the investigation has indicated that the use of the system is limited to maximum deflections of one … more
Date: June 1938
Creator: Soulé, H. A. & Hootman, James A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The increase in frictional resistance caused by various types of rivet heads as determined by tests of planing surfaces

Description: "The increase in the frictional resistance of a surface caused by the presence of rivet heads was determined by towing four planing surfaces of the same dimensions. One surface was smooth and represented a surface without rivet heads or one with perfectly flush countersunk rivets. The other three surfaces were each fitted with the same number of full-size rivet heads but of a different type arranged in the same pattern on each surface" (p. 1).
Date: May 1938
Creator: Truscott, Starr & Parkinson, J. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Tests of a Clark Y Wing Having Split Flaps With Gaps

Description: "Tests were made of the Clark Y wing having split flaps with a gap between the flap and the lower surface of the wing. Lift, drag, and pitching moments were measured for the wing with three different sizes of flap. It was found that any gap between the flap and the wing reduced the lift, the drag, and the pitching moments, but that the center-of-pressure movement and the ratio of lift to drag were little affected" (p. 1).
Date: May 1938
Creator: Wenzinger, Carl J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Tests of Carburetor-Intake Rams

Description: "An investigation was conducted in the NACA 20-foot wind tunnel of the ramming effect of three general types of carburetor intake rams for radial engines, namely, the internal constant area type, the external constant area type, and the external expanding type. The rams were installed on a radial air- cooled engine nacelle, and tests were made with and without the propeller operating. The results indicated that the external types having entrances near the front of the engine cowling gave the gr… more
Date: January 1938
Creator: Highley, Frank H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fatigue Testing of Wing Beam by the Resonance Method

Description: "Preliminary fatigue tests on two aluminum-alloy wing-beam specimens subjected to reversed axial loading are described. The motion used consists in incorporating one or two reciprocating motors in a resonance system of which the specimen is the spring element. A description is given of the reciprocating motors, and of the method of assembling and adjusting the vibrating system" (p. 1).
Date: August 1938
Creator: Bleakney, William M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wind-tunnel investigation of rectangular and tapered NACA 23012 wings with plain ailerons and full-span split flaps

Description: An investigation was made to determine the aerodynamic properties of rectangular and tapered NACA 23012 wings with plain ailerons and a full-span split flap, the flap retracting ahead of the ailerons. Measurements were made of lift and drag and of pitching, rolling, yawing, and hinge moments for all conditions of full-span flaps neutral and deflected at different chord locations. The results of the tests showed that a 0.20c(sub w) full span split flap located at approximately the 0.75c(sub w) p… more
Date: August 1938
Creator: Wenzinger, Carl J. & Ames, Milton B., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Improvement of aileron effectiveness by the prevention of air leakage through the hinge gap as determined in flight

Description: "A flight investigation was made of the increase in effectiveness of ailerons that can be obtained by preventing flow of air through the wing at the hinges and of the possibility of reducing the aileron operating force by replacing ailerons having normal open hinge gaps with narrower but equally effective ailerons having sealed hinge gaps. Tests were made with a Fairchild 22 airplane with two sizes of plain unbalanced ailerons, one set having a chord equal to 0.18c, and the other chord equal to… more
Date: January 1938
Creator: Soulé, H. A. & Gracey, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gyroscopic Instruments for Instrument Flying

Description: The gyroscopic instruments commonly used in instrument flying in the United States are the turn indicator, the directional gyro, the gyromagnetic compass, the gyroscopic horizon, and the automatic pilot. These instruments are described. Performance data and the method of testing in the laboratory are given for the turn indicator, the directional gyro, and the gyroscopic horizon. Apparatus for driving the instruments is discussed.
Date: September 1938
Creator: Brombacher, W. G. & Trent, W. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The effects of partial-span plain flaps on the aerodynamic characteristics of a rectangular and a tapered Clark Y wing

Description: An investigation was made to determine the aerodynamic characteristics of tapered and rectangular wings with partial-span plain flaps. Two Clark Y airfoils equipped with center section and with tip-section flaps were tested. The results showed that the aerodynamic characteristics of partial-span plain flaps were, in general, similar to those of split flaps of the same span, but that the lift and the drag were less for the wing with plain flaps than for the wing with split flaps of comparable si… more
Date: September 1938
Creator: House, R. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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