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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 ef… more
Date: January 17, 1934
Creator: Wheatley, John B.
Partner: UNT Libraries Government Documents Department
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Aerodynamic principles of the direct lifting propeller

Description: From Summary: "The purpose of this report is to make the complicated processes on the direct-lift propeller amenable to analysis and observation. This is accomplished by placing the physical phenomena, starting with the most elementary process, in the foreground, while limiting the mathematical treatment to the most essential in view of the fundamental defects of the theorems. Comparison with model experiments supplements and corroborates the theoretical results."
Date: January 1934
Creator: Schrenk, Martin
Partner: UNT Libraries Government Documents Department
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Aircraft Accidents: Method of Analysis

Description: The revised report includes the chart for the analysis of aircraft accidents, combining consideration of the immediate causes, underlying causes, and results of accidents, as prepared by the special committee, with a number of the definitions clarified. A brief statement of the organization and work of the special committee and of the Committee on Aircraft Accidents; and statistical tables giving a comparison of the types of accidents and causes of accidents in the military services on the one … more
Date: January 28, 1930
Creator: Committee on Aircraft Accidents
Partner: UNT Libraries Government Documents Department
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Aircraft Woods: Their Properties, Selection, and Characteristics

Description: From Summary: "This report presents, further, information on the properties of various other native species of wood compared with spruce, and discusses the characteristics of a considerable number of them from the standpoint of their possible application in aircraft manufacture to supplement the woods that are now most commonly used."
Date: January 1, 1930
Creator: Markwardt, L. J.
Partner: UNT Libraries Government Documents Department
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Airfoil Pressure Distribution Investigation in the Variable Density Wind Tunnel

Description: Report presents the results of wind tunnel tests of pressure distribution measurements over one section each of six airfoils. Pressure distribution diagrams, as well as the integrated characteristics of the airfoils, are given for both a high and a low dynamic scale or, Reynolds number VL/V, for comparison with flight and other wind-tunnel tests, respectively. It is concluded that the scale effect is very important only at angles of attack near the burble.
Date: January 14, 1930
Creator: Jacobs, Eastman N.; Stack, John & Pinkerton, Robert M.
Partner: UNT Libraries Government Documents Department
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Airship Model Tests in the Variable Density Wind Tunnel

Description: This report presents the results of wind tunnel tests conducted to determine the aerodynamic characteristics of airship models. Eight Goodyear-Zeppelin airship models were tested in the original closed-throat tunnel. After the tunnel was rebuilt with an open throat a new model was tested, and one of the Goodyear-Zeppelin models was retested. The results indicate that much may be done to determine the drag of airships from evaluations of the pressure and skin-frictional drags on models tested at… more
Date: January 27, 1931
Creator: Abbott, Ira H.
Partner: UNT Libraries Government Documents Department
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An Analytical and Experimental Study of the Effect of Periodic Blade Twist on the Thrust, Torque, and Flapping Motion of an Autogiro Rotor

Description: From Summary: "An analysis is made of the influence on autogiro rotor characteristics of a periodic blade twist that varies with the azimuth position of the rotor blade and the results are compared with experimental data. The analysis expresses the influence of this type of twist upon the thrust, torque, and flapping motion of the rotor. The check against experimental data shows that the periodic twist has a pronounced influence on the flapping motion and that this influence is accurately predi… more
Date: January 28, 1937
Creator: Wheatley, John B.
Partner: UNT Libraries Government Documents Department
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The Armstrong Whitworth A.W. 16 Military Airplane (British): A Single-Seat Biplane

Description: Circular presenting a description of the A.W. XVI, which is a single-bay staggered biplane of metal construction with a clean external design. A description of the tail unit, control system, cockpit, fuselage, characteristics, performance, drawings, and photographs are provided.
Date: January 1932
Partner: UNT Libraries Government Documents Department
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The Buckling of Curved Tension-Field Girders

Description: "The present paper reports on experiments made to determine the buckling load under shear of circular curved tension-field webs. The buckling load of the webs may be expressed with reference to the buckling load of the stiffeners. It is found that within the explored range the buckling load is approximately twice as great as that of the identically stiffened flat wall of equal web depth" (p. 1).
Date: January 1938
Creator: Limpert, G.
Partner: UNT Libraries Government Documents Department
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The calculation of take-off run

Description: From Summary: "A comparatively simple method of calculating length of take-off run is developed from the assumption of a linear variation in net accelerating force with air speed and it is shown that the error involved is negligible. Detailed instructions are given for application of the formula and for the calculation of all factors involved."
Date: January 1934
Creator: Diehl, Walter S.
Partner: UNT Libraries Government Documents Department
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Calculation of the Aerodynamic Characteristics of Tapered Wings With Partial-Span Flaps

Description: "Factors derived from wing theory are presented. By means of these factors, the angle of zero lift, the lift-curve slope, the pitching moment, the aerodynamic-center position, and the induced drag of tapered wings with partial-span flaps may be calculated. The factors are given for wings of aspect ratios 6 and 10 , of taper ratios from 0.25 to 1.00, and with flaps of various length. An example is presented of the method of application of the factors. Fair agreement with experimental results is … more
Date: January 23, 1939
Creator: Pearson, Henry A. & Anderson, Raymond F.
Partner: UNT Libraries Government Documents Department
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Calculation of the Induced Efficiency of Heavily Loaded Propellers Having Infinite Number of Blades

Description: Report presenting an approximate method of computing the induced efficiency of heavily loaded propellers in suitable form for extension to finite number of blades and a comparison of results obtained using the method with the data of the Betz-Helmbold theory for heavily loaded propellers.
Date: January 1939
Creator: Lösch, F.; Kramer, K. N.; Bock, G. & Nikodemus, R.
Partner: UNT Libraries Government Documents Department
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Clerget 100 Hp Heavy-Oil Engine

Description: A complete technical description of the Clerget heavy-oil engine is presented along with the general characteristics. The general characteristics are: 9 cylinders, bore 120 mm, stroke 130 mm, four-stroke cycle engine, rated power limited to 100 hp at 1800 rpm; weight 228 kg; propeller with direct drive and air cooling. Moving parts, engine block, and lubrication are all presented.
Date: January 1931
Creator: Léglise, Pierre
Partner: UNT Libraries Government Documents Department
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Coefficients of Flow of Standard Nozzles

Description: We first undertook experiments with air, devoted principally to the investigation of the disturbances due to the differences in the nature of the flow to the nozzle. The difficulty of measuring the air, however, caused us to experiment with water. Due to the possibility of measuring the capacity of the container, this method was much more accurate than measuring with Pitot tobes.
Date: January 1930
Creator: Mueller, H. & Peters, H.
Partner: UNT Libraries Government Documents Department
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Collection of wind-tunnel data on commonly used wing sections

Description: This report groups in a uniform manner the aerodynamic properties of commonly used wing sections as determined from tests in various wind tunnels. The data have been collected from reports of a number of laboratories. Where necessary, transformation has been made to the absolute system of coefficients and tunnel wall interference corrections have been applied. Tables and graphs present the data in the various forms useful to the engineer in the selection of a wing section.
Date: January 1930
Creator: Louden, F. A.
Partner: UNT Libraries Government Documents Department
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Combating Airplane Fires

Description: This report provides a summary of the important steps to be taken in combating airplane fires. Some considerations and ways of preventing fires from developing are provided.
Date: January 1930
Creator: Brunat, Henri
Partner: UNT Libraries Government Documents Department
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The Comparative Performance of Superchargers

Description: "This report presents a comparison of superchargers on the basis of the power required to compress the air at a definite rate, and on the basis of the net engine power developed at altitudes from 0 to 40,000 feet. The investigation included geared centrifugal, turbine-driven centrifugal, roots, and vane-type superchargers. It also includes a brief discussion of the mechanical limitations of each supercharger and explains how the method of control affects the power requirements" (p. 425).
Date: January 13, 1931
Creator: Schey, Oscar W.
Partner: UNT Libraries Government Documents Department
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A comparison of several methods of measuring ignition lag in a compression-ignition engine

Description: "The ignition lag of a fuel oil in the combustion chamber of a high speed compression-ignition engine was measured by three different methods. The start of injection of the fuel as observed with a Stoborama was taken as the start of the period of ignition lag in all cases. The end of the period of ignition lag was determined by observation of the appearance of incandescence in the combustion chamber, by inspection of a pressure-time card for evidence of pressure rise, and by analysis of the ind… more
Date: January 1934
Creator: Spanogle, J. A.
Partner: UNT Libraries Government Documents Department
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Contribution to the Study of Normal Burning in Gaseous Carbureted Mixtures: Part 1

Description: In the present study it is proposed to provide an equipment permitting the study of the propagation of the region of reaction in mixtures of air and carbureted gases enclosed within a cylinder. Ignition is produced at the end of compression by an electric spark. With this apparatus it is proposed to determine: 1) the influence of the richness of the explosive mixture on the rate of flame propagation; 2) the influence of the degree of volumetric compression on one of the hydrocarbons; 3) the inf… more
Date: January 1930
Creator: Duchene, M. R.
Partner: UNT Libraries Government Documents Department
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The D.V.L. Gliding-Angle Control (W. Hübner Design)

Description: This report describes a device for arbitrary enlargement of the gliding angle of airplanes, especially of such with flat gliding angle and difficult landing characteristics. The D.V.L. gliding angle control (design, Hubner) permits a local interruption of the lift distribution along the span and consequently an increased induced drag. The mechanism comprises two wing rudders operated by lever from the pilot's cockpit. Said rudders are fitted on the top side of the wing near the leading edge. Th… more
Date: January 1933
Creator: Hübner, Walter & Pleines, Wilhelm
Partner: UNT Libraries Government Documents Department
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The Design of Airplane Wing Ribs

Description: "The purpose of this investigation was to obtain information for use in the design of truss and plywood forms, particularly with reference to wing ribs. Tests were made on many designs of wing ribs, comparing different types in various sizes. Many tests were also made on parallel-chord specimens of truss and plywood forms in place of the actual ribs and on parts of wing ribs, such as truss diagonals and sections of cap strips" (p. 223).
Date: January 8, 1930
Creator: Newlin, J. A. & Trayer, George W.
Partner: UNT Libraries Government Documents Department
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