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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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Air Force Tests of Sperry Messenger Model With Six Sets of Wings

Description: From Summary: "The purpose of this test was to compare six well-known airfoils, the R.A.F 15, U.S.A. 5, U.S.A. 27, U.S.A. 35-B, Clark Y, and Gottingen 387, fitted to the Sperry Messenger model, at full scale Reynolds number as obtained in the variable density wind tunnel of the National Advisory Committee for Aeronautics; and to determine the scale effect on the model equipped with all the details of the actual airplane. The results show a large decrease in minimum drag coefficient upon increas… more
Date: January 20, 1927
Creator: Shoemaker, James M.
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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Airplane stress analysis

Description: Report presents stress analysis of individual components of an airplane. Normal and abnormal loads, sudden loads, simple stresses, indirect simple stresses, resultant unit stress, repetitive and equivalent stress, maximum steady load and stress are considered.
Date: January 1918
Creator: Zahm, A. F. & Crook, L. H.
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 Analysis of Pressure Studies and Experimental and Theoretical Downwash and Sidewash Behind Five Pointed-Tip Wings at Supersonic Speeds

Description: "Flow-angle and pressure surveys behind five, thin, pointed-tip wings of varying plan form have been made at Mach numbers 1.62 and 2.41. Schlieren studies at a Mach number 1.93 for the same five plan-form wings were made to illustrate the behavior of the vortex sheet. The surveys were conducted at 1.5, 3, and 4 root chords behind three triangular wings of 50 degree, 63 degree, and 72 degree leading-edge sweep angle, and behind the 50 degree triangular wing reversed" (p. 1067).
Date: January 22, 1954
Creator: Boatright, William B.
Partner: UNT Libraries Government Documents Department
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Analysis of the effects of wing interference on the tail contributions to the rolling derivatives

Description: From Introduction: "This report presents calculations of the angularity of the air stream with respect to the vertical tail for a rolling airplane, the interference effects of the wing being taken into account. A discussion of the factors which enter into the calculations is given and equations for applying the side-wash results to the determination of the tail contributions to the rolling-stability derivatives are included. The results are compared with some available experimental data."
Date: January 24, 1951
Creator: Michael, William H., Jr.
Partner: UNT Libraries Government Documents Department
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An Analysis of the Full-Floating Journal Bearing

Description: Report discussing an analysis of the operating characteristics of a full-floating journal bearing, a bearing in which a floating sleeve is located between the journal and bearing surfaces, is presented together with charts from which the performance of such bearings may be predicted.
Date: January 1, 1947
Creator: Shaw, M. C. & Nussdorfer, T. J., Jr.
Partner: UNT Libraries Government Documents Department
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Analysis of variation of piston temperature with piston dimensions and undercrown cooling

Description: From Summary: "A theoretical analysis is presented that permits estimation of the changes in piston-temperature distribution induced by variations in the crown thickness, the ring-groove-pad thickness, and the undercrown surface heat-transfer coefficient. The analysis consists of the calculation of operating temperatures at various points in the piston body on the basis of the experimentally determined surface heat-transfer coefficients and boundary-region temperatures, as well as arbitrarily s… more
Date: January 15, 1948
Creator: Sanders, J. C. & Schramm, W. B.
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 application of propeller test data to design and performance calculations

Description: From Summary: "This report is a study of a test data on a family of Durand's propellers (nos. 3, 7, 11, 82, 113, 139), which is fairly representative of conventional design. The test data are so plotted that the proper pitch and diameters for any given set of conditions are readily obtained. The same data are plotted in other forms which may be used for calculating performance when the ratio of pitch to diameter is known. These new plots supply a means for calculating the performance, at any al… more
Date: January 1925
Creator: Diehl, Walter S.
Partner: UNT Libraries Government Documents Department
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Application of Radial-Equilibrium Condition to Axial-Flow Compressor and Turbine Design

Description: "Basic general equations governing the three-dimensional compressible flow of gas through a compressor or turbine are given in terms of total enthalpy, entropy, and velocity components of the gas. Two methods of solution are obtained for the simplified, steady axially symmetric flow; one involves the use of a number of successive planes normal to the axis of the machine and short distances apart, and the other involves only three stations for a stage in which an appropriate radial-flow path is … more
Date: January 1, 1949
Creator: Wu, Chung-Hua & Wolfenstein, Lincoln
Partner: UNT Libraries Government Documents Department
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Bending moments, envelope, and cable stresses in non-rigid airships

Description: This report describes the theory of calculating the principal stresses in the envelope of a nonrigid airship used by the Bureau of Aeronautics, United States Navy. The principal stresses are due to the gas pressure and the unequal distribution of weight and buoyancy, and the concentrated loads from the car suspension cables. The second part of the report deals with the variations of tensions in the car suspension cables of any type of airship, with special reference to the rigid type, due to th… more
Date: January 1923
Creator: Burgess, C. P.
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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Calculations of Economy of 18-Cylinder Radial Aircraft Engine With Exhaust-Gas Turbine Geared to the Crankshaft

Description: Calculations based on dynamometer test-stand data obtained on an 18-cylinder radial engine were made to determine the improvement in fuel consumption that can be obtained at various altitudes by gearing an exhaust-gas turbine to the engine crankshaft in order to increase the engine-shaft work.
Date: January 1, 1945
Creator: Hannum, Richard W. & Zimmerman, Richard H.
Partner: UNT Libraries Government Documents Department
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Characteristics of a boat type seaplane during take-off

Description: This report, on the planing and get-away characteristics of the F-5-L, gives the results of the second of a series of take-off tests on three different seaplanes conducted by the National Advisory Committee for Aeronautics at the suggestion of the Bureau of Aeronautics, Navy Department. The single-float seaplane was the first tested and the twin-float seaplane is to be the third. The characteristics of the boat type were found to be similar to the single float, the main difference being the inc… more
Date: January 1926
Creator: Crowley, J. W., Jr. & Ronan, K. M.
Partner: UNT Libraries Government Documents Department
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Characteristics of a single float seaplane during take-off

Description: At the request of the Bureau of Aeronautics, Navy Department, the National Advisory Committee for Aeronautics at Langley Field is investigating the get-away characteristics of an N-9H, a DT-2, and an F-5l, as representing, respectively, a single float, a double float, and a boat type of seaplane. This report covers the investigation conducted on the N-9H. The results show that a single float seaplane trims aft in taking off. Until a planing condition is reached the angle of attack is about 15 d… more
Date: January 1925
Creator: Crowley, J. W., Jr. & Ronan, K. M.
Partner: UNT Libraries Government Documents Department
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Characteristics of a twin-float seaplane during take-off

Description: This report presents the results of an investigation of the planing and get-away characteristics of three representative types of seaplanes, namely, single float, boat, and twin float. The experiments carried out on the single float and boat types have been reported on previously. This report covers the investigation conducted on the twin-float seaplane, the DT-2, and includes as an appendix, a brief summary of the results obtained on all three tests. At low-water speeds, 20 to 30 miles per hou… more
Date: January 1927
Creator: Crowley, John W., Jr. & Ronan, K. M.
Partner: UNT Libraries Government Documents Department
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Charts for graphical estimation of airplane performance

Description: This report contains a series of charts which were developed in order to simplify the estimation of airplane performance. Charts are given for estimating propeller diameter and efficiency, maximum speed, initial rate of climb, absolute ceiling, service ceiling, climb in 10 minutes, time to climb to any altitude, maximum speed at any altitude, and endurance. A majority of these charts are based on the equations given in NACA Technical Report no. 173. Plots of pressure and density against altitud… more
Date: January 1925
Creator: Diehl, Walter S.
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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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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