National Advisory Committee for Aeronautics (NACA) - 1,438 Matching Results

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The Analysis of Aircraft Structures as Space Frameworks: Method Based on the Forces in the Longitudinal Members

Description: The following examples do not take up the discussion of viewpoints to be heeded in determining the design of a framework for given external conditions. Rather they are methods for determining the forces in airplane fuselages and wings, though similar considerations are applied to certain simple cases of a different kind. The object of this treatise is to summarize and amplify these considerations from definite viewpoints.
Date: July 1929
Creator: Wagner, Herbert
Partner: UNT Libraries Government Documents Department
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Analysis of Experimental Investigations of the Planing Process of the Surface of Water

Description: Pressure distribution and spray measurements were carried out on rectangular flat and V-bottom planing surfaces. Lift, resistance, and center of pressure data are analyzed and it is shown how these values may be computed for the pure planing procees of a flat or V-bottom suface of arbitrary beam, load and speed, the method being illustrated with the aid of an example.
Date: March 1944
Creator: Sottorf, W.
Partner: UNT Libraries Government Documents Department
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Analysis of flight and wind-tunnel tests on Udet airplanes with reference to spinning characteristics

Description: This report presents an analysis of results of wind-tunnel tests conducted at the D.V.L. Values were determined for the effectiveness of all the controls at various angles of attack. The autorotation was studied by subjecting the rotating model to an air blast.
Date: March 1929
Creator: Herrmann, H.
Partner: UNT Libraries Government Documents Department
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Analysis of Spinning in a Monoplane Wing by the Induction Method as Compared With the Strip Method

Description: The problem of autorotation has been attacked by various authors, in particular Fuchs and Schmidt who applied the so-called strip method which is based upon the assumption that the forces and moments per unit length acting in each section of the wing are equal to those on an infinite cylindrical wing of equal section in an air flow of intensity and direction resulting from the apparent relative motion of this section with respect to the surrounding air. In other words they disregarded the induc… more
Date: June 1934
Creator: Poggi, L.
Partner: UNT Libraries Government Documents Department
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Analytical methods for computing the polar curves of airplanes

Description: This report presents a method of calculating polar curves which is at least as precise as graphical methods, but it more rapid. Knowing the wind tunnel test of a wing and the performances of an airplane of the same profile, it is easy to verify the characteristic coefficients and, at the same time, the methods determining induced resistances.
Date: March 1921
Creator: Le Sueur
Partner: UNT Libraries Government Documents Department
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Analytical Study of Shimmy of Airplane Wheels

Description: The problem of shimmy of a castering wheel, such as the nose wheel of a tricycle gear airplane, is treated analytically. The flexibility of the tire is considered to be the primary cause of shimmy. The rather simple theory developed agrees rather well with previous experimental results. The author suggests that shimmy may be eliminated through a suitable choice of landing gear dimensions in lieu of a damper.
Date: September 1952
Creator: Bourcier de Carbon, Christian
Partner: UNT Libraries Government Documents Department
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Analytical Theory of the Campini Propulsion System

Description: "The present report deals exclusively with the particular jet-propulsion system mentioned in the cited reports. The discussion is limited, for the present, to the analytical study of the efficiency and the consumption for the case of application to aircraft and to the plotting of the practical operating curves secured theoretically by the use of suitable experimental factors" (p. 1).
Date: March 1942
Creator: Campini, S.
Partner: UNT Libraries Government Documents Department
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Analytical Treatment of Normal Condensation Shock

Description: "The condensation of water vapor in an air has the following consequences: acquisition of heat (liberated heat vaporization; loss of mass on the part of the flowing gas (water vapor is converted to liquid); change in the specific gas constants and of the ratio k of the specific heats (caused by change of gas composition). A discontinuous change of state is therefore connected with the condensation; schlieren photographs of supersonic flows in two-dimensional Laval nozzles show two intersecting … more
Date: July 1947
Creator: Heybey
Partner: UNT Libraries Government Documents Department
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Apparatus for Measurements of Time and Space Correlation

Description: The report describes a brief review is made of improvements to an experimental apparatus for time and space correlation designed for study of turbulence. Included is a description of the control of the measurements and a few particular applications.
Date: April 1955
Creator: Favre, Alexandre; Gaviglio, J. & Dumas, R.
Partner: UNT Libraries Government Documents Department
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The apparent width of the plate in compression

Description: This report discusses an investigation that treats the load capacity of a rectangular plate stressed in compression on one direction (x) beyond the buckling limit and the plate is rotatable (i.e., free from moments) supported at all four sides by bending-resistant beams.
Date: July 1937
Creator: Marguerre, Karl
Partner: UNT Libraries Government Documents Department
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Application and testing of transparent plastics used in airplane construction

Description: This report discusses the efforts being made to remove the source of danger to passengers arising from the fracturing of silicate glass and some of the alternatives presented include: single-layer safety glass, multi-layer safety glass, transparent plastic resins.
Date: November 1938
Creator: Riechers, K. & Olms, J.
Partner: UNT Libraries Government Documents Department
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Application of the Method of Coordinate Perturbation to Unsteady Duct Flow

Description: The method of coordinate perturbation is applied to the unsteady flow of a compressible fluid in ducts of variable cross section. Solutions, in the form of perturbation series, are obtained for unsteady flows in ducts for which the logarithmic derivative of area variation with respect to the space coordinate is a function of the 'smallness' parameter of the perturbation series. This technique is applied to the problem of the interaction of a disturbance and a shock wave in a diffuser flow. It i… more
Date: September 1958
Creator: Himmel, Seymour C.
Partner: UNT Libraries Government Documents Department
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Application of the Methods of Gas Dynamics to Water Flows With Free Surface 1: Flows With No Energy Dissipation

Description: The application is treated in sufficient detail to facilitate as much as possible its application by the engineer who is less familiar with the subject. The present work was undertaken with two objects in view. In the first place, it is considered as a contribution to the water analogy of gas flows, and secondly, a large portion is devoted to the general theory of the two-dimensional supersonic flows.
Date: March 1940
Creator: Preiswerk, Ernst
Partner: UNT Libraries Government Documents Department
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Application of the Methods of Gas Dynamics to Water Flows With Free Surface 2: Flows With Momentum Discontinuities (Hydraulic Jumps)

Description: In this paper an introduction to shock polar diagrams is given which then leads into an examination of water depths in hydraulic jumps. Energy loss during these jumps is considered along with an extended look at elementary solutions of flow. An experimental test set-up is described and the results presented.
Date: March 1940
Creator: Preiswerk, Ernst
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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Applying the results of experiments on small models in the wind tunnel to the calculation of full-sized aircraft

Description: This report presents the attempt to develop a law which will permit the use of results obtained on small models in a tunnel for the calculation of full-sized airplanes, or if it exists, a law of similitude relating air forces on a full-sized plane to those on a reduced scale model.
Date: April 1922
Creator: Robert
Partner: UNT Libraries Government Documents Department
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Approximate Calculation of Multispar Cantilever and Semicantilever Wings With Parallel Ribs Under Direct and Indirect Loading

Description: A method is presented for approximate static calculation, which is based on the customary assumption of rigid ribs, while taking into account the systematic errors in the calculation results due to this arbitrary assumption. The procedure is given in greater detail for semicantilever and cantilever wings with polygonal spar plan form and for wings under direct loading only. The last example illustrates the advantages of the use of influence lines for such wing structures and their practical int… more
Date: August 1932
Creator: Sänger, Eugen
Partner: UNT Libraries Government Documents Department
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Approximate Calculation of the Static Longitudinal Stability of Airplanes

Description: It seems desirable to have some simple method for calculating quickly and with sufficient accuracy: 1) the correct position of the center of gravity; 2) the requisite tail-group dimensions; 3) and the course of the wing and tail-group moments. In out deductions, we will first replace the biplane (disregarding the effect of stagger, decalage and induced drag) by an equivalent monoplane, whose dimensions and position in space can be approximately determined in a simple manner.
Date: November 1926
Creator: Bienen, Theodor
Partner: UNT Libraries Government Documents Department
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An Approximate Method for Calculation of the Laminar Boundary Layer with Suction for Bodies of Arbitrary Shape

Description: From Summary: "Various ways were tried recently to decrease the friction drag of a body in a flow; they all employ influencing the boundary layer. One of them consists in keeping the boundary layer Laminar by suction; promising tests have been carried out. Since for large Reynolds numbers the friction drag of the laminar boundary layer is much lower than that of the turbulent boundary layer, a considerable saving in drag results from keeping the boundary layer laminar, even with the blower powe… more
Date: March 1949
Creator: Schlichting, H.
Partner: UNT Libraries Government Documents Department
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Approximation method for determining the static stability of a monoplane glider

Description: The calculations in this paper afford an approximate solution of the static stability. A derivation of the formulas for moment coefficient of a wing, moment coefficient of elevator, and the total moment of the combined wing and elevator and the moment coefficient with reference to the center of gravity are provided.
Date: November 1927
Creator: Lippisch, A.
Partner: UNT Libraries Government Documents Department
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The Art of Writing Scientific Reports

Description: As the purpose of the report is to transmit as smoothly and as easily as possible, certain facts and ideas, to the average person likely to read it, it should be written in a full and simple enough manner to be comprehended by the least tutored, and still not be boring to the more learned readers.
Date: March 1921
Creator: Norton, F. H.
Partner: UNT Libraries Government Documents Department
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