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Fuel Consumption of a Carburetor Engine at Various Speeds and Torques

Description: "An investigation was conducted to obtain fuel-consumption curves for a single-cylinder engine with a Wright 1820-G and Pratt & Whitney 1340-H cylinder at varying speeds, manifold pressures, and air-fuel ratios. The 1340- H cylinder was tested at speeds from 1,200 to 2,400 r.p.m. and at manifold pressures from 21 to 38 inches of mercury absolute. Less than extensive tests were made of the 1820-G cylinder. The results of the tests showed that the minimum brake fuel consumption was obtained when … more
Date: June 1938
Creator: Schey, Oscar W. & Clark, J. Denny
Partner: UNT Libraries Government Documents Department
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The Pegmatites at Tinton, South Dakota

Description: Report issued by the U.S. Bureau of Mines on the pegmatite deposits found near Tinton, South Dakota. The properties, and geology of the deposits are presented. This report includes tables, and maps.
Date: June 1938
Creator: Hess, Frank L. & Bryan, Barnabas, Jr.
Partner: UNT Libraries Government Documents Department
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Principles involved in the cooling of a finned and baffled cylinder

Description: An analysis of the cooling problems for a finned cylinder is made on the basis of the known fundamental principles of heat transfer from pipes. Experimental results that support the analysis are presented. The results of previous investigations on the problem are evaluated on the basis of the analysis and the results. An illustration of the application of these principles to a specific problem is included.
Date: June 1938
Creator: Brevoort, M. J.
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.
Partner: UNT Libraries Government Documents Department
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Theoretical Study of Various Airplane Motions After Initial Disturbance

Description: The present investigation may be considered as preliminary to the study of automatic stabilizers. We have sought to determine first how an airplane of average characteristics reacts against the principal disturbances it may encounter. Without entering into the general study of automatic stabilizers, the present work suggests the idea of a stabilizer whose sensitive member would be a wind vane or pressure plate.
Date: June 1938
Creator: Haus
Partner: UNT Libraries Government Documents Department
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Determination of boundary-layer transition on three symmetrical airfoils in the NACA full-scale wind tunnel

Description: For the purpose of studying the transition from laminar to turbulent flow, boundary-layer measurements were made in the NACA full-scale wind tunnel on three symmetrical airfoils of NACA 0009, 0012, and 0018 sections. The effects of variations in lift coefficient, Reynolds number, and airfoil thickness on transition were investigated. Air speed in the boundary layer was measured by total-head tubes and by hot wires; a comparison of transition as indicated by the two techniques was obtained. The … more
Date: May 26, 1938
Creator: Silverstein, Abe & Becker, John V.
Partner: UNT Libraries Government Documents Department
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The Effect of Compressibility on Eight Full-Scale Propellers Operating in the Take-Off and Climbing Range

Description: "Tests were made of eight full-scale propellers of different shape at various tip speeds up to about 1,000 feet per second. The range of blade-angle settings investigated was from 10 degrees to 30 degrees at the 0.75 radius. The results indicate that a loss in propulsive efficiency occurred at tip speeds from 0.5 to 0.7 the velocity of sound for the take-off and climbing conditions" (p. 517).
Date: May 18, 1938
Creator: Biermann, David & Hartman, Edwin P.
Partner: UNT Libraries Government Documents Department
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The effect of air-passage length on the optimum fin spacing for maximum cooling

Description: The effect on cooling of baffle length with optimum cylinder finning is discussed. Results from tests of several streamlined cylinders are given. It is shown that by employing several baffles the cooling can be increased several times.
Date: May 1938
Creator: Brevoort, Maurice J.
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.
Partner: UNT Libraries Government Documents Department
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Effects of Simulated Ice Formation on the Aerodynamic Characteristics of an Airfoil

Description: Report presenting an investigation of the size and distribution of ice particles on the wings of aircraft and how they affect the aerodynamic characteristics. A simulated ice formation was generated from survey information received from aircraft pilots and was tested to determine the impact on the lift characteristics.
Date: May 1938
Creator: Gulick, Beverly G.
Partner: UNT Libraries Government Documents Department
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Flow Characteristics, Composition, and Some Liquid-Phase Properties of Hydrocarbon Fluids From a "Combination" Well

Description: Report issued by the U.S. Bureau of Mines on the properties of fluids produced from combination wells. The characteristics of test results of these fluids are described and presented. This report includes tables, graphs, illustrations, and photographs.
Date: May 1938
Creator: Eilerts, C. K. & Schellhardt, M. A.
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.
Partner: UNT Libraries Government Documents Department
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The Influence of Notches Under Static Stress

Description: From the described experiments it is seen that notches are a potential source of strength decrease even under static stress, which the designer must take into consideration. Section I is a general treatment of notch influence under the various types of stresses. Section II treats the influence of notches in thin sheet as is used in airplane construction.
Date: May 1938
Creator: Matthaes, K.
Partner: UNT Libraries Government Documents Department
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Load Tests on a Stiffened Circular Cylindrical Shell

Description: The present report describes tests in which the stress distribution may be determined in a stiffened circular cylindrical shell loaded longitudinally at four symmetrically situated points. As being of particular importance are the cases investigated of groups of bending and arching or convexing forces, respectively. From the stress measurements on the longitudinal stiffeners, the shear stresses and the bulkhead ring stresses in the skin could be evaluated.
Date: May 1938
Creator: Schapitz, E. & Krümling, G.
Partner: UNT Libraries Government Documents Department
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On the Determination of the Take-Off Characteristics of a Seaplane

Description: The present paper presents an attempt to coordinate the available theoretical and experimental data on planing surfaces so as to develop an approximate analytical method for the determination of the water resistance of a seaplane without any preliminary towing tests in the tank.
Date: May 1938
Creator: Perelmuter, A.
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.
Partner: UNT Libraries Government Documents Department
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Approximate Stress Analysis of Multistringer Beams With Shear Deformation of the Flanges

Description: "The problem of the skin-stringer combinations used as axially loaded panels or as covers for box beams is considered from the point of view of the practical stress analyst. By a simple substitution the problem is reduced to the problem of the single-stringer structure, which has been treated in NACA Report no. 608. The method of making this substitution is essentially empirical; in order to justify it, comparisons are shown between calculations and strain-gage tests of three beams tested by th… more
Date: April 20, 1938
Creator: Kuhn, Paul
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 for… more
Date: April 19, 1938
Creator: Pearson, Henry A. & Jones, Robert T.
Partner: UNT Libraries Government Documents Department
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Tests of Two Full-Scale Propellers With Different Pitch Distributions, at Blade Angles Up to 60 Degrees

Description: "Two 3-blade 10-foot propellers were operated in front of a liquid-cooled engine nacelle. The propellers differed only in pitch distribution; one had normal distribution (nearly constant pitch for a blade angle of 15 degrees at 0.75 radius), and the other had the pitch of the tip sections decreased with respect to that for the shank sections (blade angle of 35 degrees for nearly constant pitch distribution). Propeller blade angles at 0.75r from 15 degrees to sixty degrees, corresponding to desi… more
Date: April 14, 1938
Creator: Biermann, David & Hartman, Edwin P.
Partner: UNT Libraries Government Documents Department
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Model Study of Plans for Channel Improvement at Dogtooth Bend, Mississippi River, Folder 1

Description: This memorandum, constitutes a report on the results of experiments conducted at the U. S. Waterways Experiment Station on a small scale model of that reach of the Mississippi River near and including Dogtooth Bend (Mile 32.7 above to Mile 4.0 below Cairo).
Date: April 2, 1938
Creator: Waterways Experiment Station (U.S.)
Partner: UNT Libraries Government Documents Department
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Aerodynamic Characteristics of a 4-Engine Monoplane Showing Effects of Enclosing the Engines in the Wing and Comparisons of Tractor- and Pusher-Propeller Arrangements

Description: Report presenting testing in the full-scale wind tunnel on a model of a large 4-engine monoplane to determine the overall aerodynamic efficiency of a conventional wing-nacelle-engine installation as compared with power-plant installations enclosed in the wing with extension shafts to the propellers. Results regarding power-on and power-off performance for the installations as well as propeller noise are provided.
Date: April 1938
Creator: Silverstein, Abe & Wilson, Herbert A., Jr.
Partner: UNT Libraries Government Documents Department
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The design of floats

Description: Following a summary of the multiplicity of domestic and foreign floats and a brief enumeration of the requirements of floats, the essential form parameters and their effect on the qualities of floats are detailed. On this basis a standard float design is developed which in model families with varying length/beam ratio and angle of dead rise is analyzed by an experimental method which permits its best utilization on any airplane.
Date: April 1938
Creator: Sottorf, W.
Partner: UNT Libraries Government Documents Department
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Engine performance and knock rating of fuels for high-output aircraft engines

Description: From Summary: "Data are presented to show the effects of inlet-air pressure, inlet-air temperature, and compression ratio on the maximum permissible performance obtained on a single-cylinder test engine with aircraft-engine fuels varying from a fuel of 87 octane number to one 100 octane number plus 1 ml of tetraethyl lead per gallon. The data were obtained on a 5-inch by 5.75-inch liquid-cooled engine operating at 2,500 r.p.m. The compression ratio was varied from 6.50 to 8.75. The inlet-air te… more
Date: April 1938
Creator: Rothrock, A. M. & Biermann, Arnold E.
Partner: UNT Libraries Government Documents Department
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