Technical Report Archive & Image Library (TRAIL) - 380 Matching Results

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The critical velocity of a body towed by a cable from an airplane

Description: It is sufficient to consider only the equations of motion of the towed body whereas those of the cable may be left out of consideration. The result obtained makes it possible to determine which factors affect the critical velocity and what modifications of the instrument are necessary for extending the upper limit of that velocity.
Date: July 1937
Creator: Koning, C. & DeHaas, T. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Boundary Layer as a Means of Controlling the Flow of Liquids and Gases

Description: According to one of the main propositions of the boundary layer theory the scarcely noticeable boundary layer may, under certain conditions, have a decisive influence on the form of the external flow by causing it to separate from the wing surface. These phenomena are known to be caused by a kind of stagnation of the boundary layer at the point of separation. The present report deals with similar phenomena. It is important to note that usually the cause (external interference) directly affects … more
Date: March 1930
Creator: Schrenk, Oskar
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Airplane Flight in the Stratosphere

Description: This brief survey of the problems encountered in high-altitude flight deals in particular with the need for high lift coefficient in the wings, large aspect ratios in the wings, and also the problem of hermetically sealing the cabin.
Date: February 1932
Creator: de Caria, Ugo
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Static Longitudinal Stability Of "Ente" Airplanes

Description: The stability conditions of Ente (duck) airplanes are investigated in this report. In developing the formulas, which afford an approximate solution, the unimportant effect of the height of the C.G. and the moment of the residual resistance are neglected. The effect of downwash from the forward horizontal empennage on the wing are also disregarded.
Date: March 1931
Creator: Kiel, Heinrich Georg
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Vortex Theory and Its Significance in Aviation

Description: This report will present ideas closely related to the vortex conception and illustrate them in the simplest possible terms. In addition to these general considerations, this report will attempt to show the application of the vortex theory in connection with the wing theory.
Date: July 1930
Creator: Betz, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Riveting in Metal Airplane Construction Part 1 : Riveting Methods and Equipment in German Metal Airplane Construction

Description: "Although all constructors in Germany use duralumin quite frequently, and prefer cold riveting exclusively for permanent (nondetachable) connections of individual structural components, their methods and equipment are very diversified. The differences are due to a great extent to the diversity of structural types and to the special shapes of the individual subassemblies. The results is that different manufacturers have developed totally different riveting methods, as well as entirely different … more
Date: December 1930
Creator: Pleines, Wilhelm
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Problems Concerning the Stability and Maneuverability of Airplanes

Description: "The stability of an airplane can be easily determined by wind-tunnel tests, especially by simple tests with models mounted wind-vane fashion. However, each stability curve plotted by this method is valid only for a certain setting of the corresponding control surface, i.e., it characterizes the stability of the airplane with the control stick in a given position. The problems thus defined are studied from the point of view of longitudinal and transverse stability. Directional stability is not … more
Date: March 1932
Creator: Biche, Jean
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Transference of Heat From a Hot Plate to an Air Stream

Description: The object of the present study was to define experimentally the field of temperature and velocity in a heated flat plate when exposed to an air stream whose direction is parallel to it, then calculate therefrom the heat transference and the friction past the flat plate, and lastly, compare the test data with the mathematical theory. To ensure comparable results, we were to actually obtain or else approximate: a) two-dimensional flow; b) constant plate temperature in the direction of the stream… more
Date: April 1931
Creator: Elias, Franz
Item Type: Refine your search to only Report
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
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mathematical treatise on the recovery from a flat spin

Description: In this mathematical investigation, made in collaboration with Dr. Wilhelm Schmidt, we interpret the temporary change (due to some disturbance) in the quantities which define the position of the airplane while in a flat spin. We further examine the effect of this change, of the means resorted to to produce the disturbance, and thus reveal the expedients available for recovering from a flat spin.
Date: November 1930
Creator: Fuchs, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Accurate Calculation of Multispar Cantilever and Semicantilever Wings With Parallel Webs Under Direct and Indirect Loading

Description: In the present report the computation is actually carried through for the case of parallel spars of equal resistance in bending without direct loading, including plotting of the influence lines; for other cases the method of calculation is explained. The development of large size airplanes can be speeded up by accurate methods of calculation such as this.
Date: March 1932
Creator: Sänger, Eugen
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Mutual Action of Airplane Body and Power Plant

Description: The present report concerns the development of general propeller performance and r.p.m. curves which, combined with the general curve of the power required for level flight, presents a complete picture of the performance. The curve of power required for level flight in this paper is only an approximation for constant profile drag coefficient, meaning that it is not suitable to unconventional wing sections.
Date: April 1932
Creator: Schrenk, Martin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of the Variations in the Velocity of the Air Flow About a Wing Profile

Description: Memorandum presenting an investigation to determine the variations in the velocity of the air when it was obliged to flow about a wing profile. Special interest was paid to the determination of velocity as compared with that of the undisturbed flow and of the velocity drop in successive planes perpendicular to the flow direction at increasing distances from the wing profile.
Date: July 1930
Creator: Repenthin, Walter
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experiments With Airplane Brakes

Description: This report begins by examining the forces on the brake shoes. For the determination of the load distribution over the shoes it was assumed that the brake linings follow Hooke's law, are neatly fitted and bedded in by wear. The assumption of Hooke's law, that is, the proportionality between compression of the lining and the absorption of force, is fulfilled to a certain extent for the loading, as becomes apparent from the load tests described further on. But there is a material discrepancy at u… more
Date: September 1931
Creator: Michael, Franz
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Elmira Soaring Contest, 1930

Description: This report details the Elmira, New York soaring contest of 1930 and provides up-current maps, experiences in piloting, distance flights, and a few details on glider design.
Date: March 1931
Creator: Hirth, Wolfram K. E.; Schempp, Martin H. & Herrick, Jack
Item Type: Refine your search to only Report
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
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of Viscosity in Speed Measurements With Double-Throat Venturi Tubes

Description: In order to clarify the viscosity effect some experiments were made in the Gottigen low-pressure tunnel with the Bruhn double-throat Venturi tube. This type of tunnel makes it possible to vary the pressure and thereby the density within wide limits and consequently, to examine the viscosity effect. This, however, did not impair the results because pressure and temperature were determined at different periods.
Date: August 1931
Creator: Peters, H.
Item Type: Refine your search to only Report
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.
Item Type: Refine your search to only Report
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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental Research on the Friction of Pivots

Description: In horology the friction between solids is of the greatest importance; one limited, however, to the application of the laws of Coulomb which, do not at all correspond with reality. This report presents a review of the subject and some general conclusions. The choice of lubricant is discussed as well as the pressure between frictional surfaces. The gears in a watch are used extensively as examples.
Date: May 1930
Creator: Jaquerod, A.; Defossez, L. & Mügeli, H
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Load Assumptions for Calculating the Strength of Airplanes

Description: "The following load assumptions shall be taken as the basis of the strength calculations. Certain definite load conditions (e.g. of flight, control, landing and transport) shall be assumed. The loads shall be assumed to be safe loads, constant or only slowly variable, and the inertia forces due to elastic deformation are accordingly disregarded. The external forces, the force of gravity and the inertia forces on the whole airplane shall produce a condition of equilibrium" (p. 1).
Date: September 1930
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Frictionless Flow in the Region Around Two Circles

Description: This investigation attempts to surpass the boundaries of pure mathematical interest in that it possesses as an example, a flow investigation in a multiply-connected region. Then the results appear to be carried out by means of an appropriate conformal representation of the region around two chosen closed curves. Thus we have the basis of an exact plane theory of the biplane.
Date: June 1931
Creator: Lagally, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurements of Vertical Air Currents in the Atmosphere

Description: To summarize, the experiments with balloons, sailplanes and light airplanes conducted thus far, reveal the vertical velocities of the air to be primarily dependent on the vertical temperature distribution. Stable stratifications result in up-and-down currents forced by the contour of the ground, which are readily recognized in flight and, if need be, may be avoided.
Date: November 1931
Creator: Lange, K. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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