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The Gyroplane: Its Principles and Its Possibilities

Description: This report begins by indicating several simple principles concerning the velocity distribution over the blades of a lifting propeller of diameter D, revolving at n revolutions per second, and animated by a horizontal movement of translation at speed V. The calculation, compared with the test data, has shown that the aerodynamic action of the air on the blades depends almost only on the velocity components in a plane at right angles to the blade span. A history of gyroplane and gyrocopter devel… more
Date: January 1937
Creator: Breguet, Louis
Partner: UNT Libraries Government Documents Department
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Detonation and Autoignition: Some Considerations on Methods of Determination

Description: This paper is a critical analysis of the methods of determination of the tendency to detonation. No attempt has been made to describe in detail the different fuels and the different methods proposed.
Date: December 1937
Creator: Boerlage, G. D.
Partner: UNT Libraries Government Documents Department
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Universal Logarithmic Law of Velocity Distribution as Applied to the Investigation of Boundary Layer and Drag of Streamline Bodies at Large Reynolds Number

Description: In the present paper we shall consider a figure of revolution, so that the formulas applicable to the more simple cases as, for example, a wing or flat plate will follow from our equations as corollaries. For checking the results of our theory, we made use of the data derived from the tests of Freeman on a 1/40-scale model of the airship "Akron" conducted in the large NACA wind tunnel. In the first part we shall derive the fundamental equation for a body of revolution according to the Karman th… more
Date: November 1937
Creator: Gurjienko, G.
Partner: UNT Libraries Government Documents Department
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Synthetic Resins in Aircraft Construction - Their Composition, Properties, Present State of Development and Application to Light Structures

Description: This report gives a brief review of the properties that have been attained with the synthetic materials with which we are at present familiar. Results of investigations are presented as well as possibilities for construction applications. Endurance strength and bonding tests are also presented.
Date: November 1937
Creator: Riechers, K.
Partner: UNT Libraries Government Documents Department
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Research and Design Problems Introduced by Increased Power Output

Description: In what follows the question of the number and geometrical arrangement of the cylinders so important in the design of high performance power units will be considered from various points of view. A discussion will be given of the possibilities of the various working processes and an investigation will be made of possible means for improving the continuous operation and take-off performance, particularly the methods of supercharging, increasing the r.p.m., and employing the two-stroke-cycle engin… more
Date: October 1937
Creator: Kurtz, Oskar
Partner: UNT Libraries Government Documents Department
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The Strength of Shell Bodies: Theory and Practice

Description: "The monocoque form of airplane construction has introduced a number of new problems to the stress calculator and the designer. The problems for the stress calculator fall into two groups: the determination of the stress condition (shell statics) and the determination of the failing strength (shell strength). The present report summarizes the most important theoretical and experimental results on this subject" (p. 1).
Date: September 1937
Creator: Ebner, H.
Partner: UNT Libraries Government Documents Department
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Charts for Checking the Stability of Plane Systems of Rods

Description: "Charts are presented for checking the stability of plane systems of rods, the use of the charts being illustrated by examples. It is also indicated how best to combine the individual members to form stable structures" (p. 1).
Date: September 1937
Creator: Borkmann, K.
Partner: UNT Libraries Government Documents Department
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The Ground Effect on Lifting Propellers

Description: In what follows an estimate will be made of the magnitude of the ground effect. For the two cases where the distance a of the propeller from the ground is very small, and very large, respectively, in comparison with the propeller radius r(sub o) the relations may be simply expressed. We consider first the effect of the ground, assuming that the thrust is held constant, as may be done by a suitable change in the propeller speed.
Date: August 1937
Creator: Betz, A.
Partner: UNT Libraries Government Documents Department
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Pressure Distribution on a Wing Section With Slotted Flap in Free Flight Tests

Description: "The pressure distribution was measured in flight on a wing section with a slotted flap for several flap deflections, and the results obtained are presented. The test apparatus and the procedure employed in obtaining the results are also described. A Fieseler type F 5 R airplane was used for the tests" (p. 1).
Date: August 1937
Creator: Kiel, Georg
Partner: UNT Libraries Government Documents Department
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The Stability of Orthotropic Elliptic Cylinders in Pure Bending

Description: "The theoretical critical bending stress of elliptic cylindrical shells is determined on the assumption of infinite shell length and absence of local instability phenomena. The results of the tests on isotropic elliptic cylindrical shells stressed in bending are compared with the theoretical results. The practical applicability of the theory is discussed" (p. 1).
Date: July 1937
Creator: Heck, O. S.
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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Contributions to the Theory of Incomplete Tension Bay

Description: The present report offers an approximate theory for the stress and deformation condition after buckling of the skin in reinforced panels and shells loaded in simple shear and compression and under combined stresses. The theory presents a unified scheme for stresses of these types. It is based upon the concept of a nonuniform stress distribution in the metal panel and its marked power of resistance against compressive stresses ("incomplete" tension bay).
Date: July 1937
Creator: Schapitz, E.
Partner: UNT Libraries Government Documents Department
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Method of Curved Models and Its Application to the Study of Curvilinear Flight of Airships: Part 2

Description: This report compares the results obtained by the aid of curved models with the results of tests made by the method of damped oscillations, and with flight tests. Consequently we shall be able to judge which method of testing in the tunnel produces results that are in closer agreement with flight test results.
Date: June 1937
Creator: Gourjienko, G. A.
Partner: UNT Libraries Government Documents Department
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Method of Curved Models and Its Application to the Study of Curvilinear Flight of Airships: Part 1

Description: In the first part of this paper we shall present the theoretical side of the problem of constructing curved model forms and the method of testing the model. In the second part we shall present a detailed account of the first experiments according to the given method, carried out with a curved model of the nonrigid airship V-2, and a comparison of the experimental results with some data of full-scale tests made with this airship in 1933.
Date: June 1937
Creator: Gourjienko, G. A.
Partner: UNT Libraries Government Documents Department
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Ground Effect - Theory and Practice

Description: The conclusion of a previous article by Pistolesi is that the increment of lift due to ground effect is largely attributable to the effect of induction of the free vortices, and is practically equivalent to a virtual increase in aspect ratio. The ground clearance was of the order of magnitude comparable to the wing chord. New reports by Le Seur and Datwyler treat the case of minimum distance from the ground and is confined to the plane problem only. The author briefly reviews these reports and … more
Date: June 1937
Creator: Pistolesi, E.
Partner: UNT Libraries Government Documents Department
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Helicopter Problems

Description: The present report deals with a number of the main problems requiring solution in the development of helicopters and concerning the lift, flying performance, stability, and drive. A complete solution is given for the stability of the helicopter with rigid blades and control surfaces. With a view to making a direct-lift propeller sufficient without the addition of auxiliary propellers, the "flapping drive" is assessed and its efficiency calculated.
Date: May 1937
Creator: Küssner, H. G.
Partner: UNT Libraries Government Documents Department
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Tandem Air Propellers

Description: Report discussing tests of 2-blade, adjustable-pitch, counterrotating tandem model propellers, adjusted to absorb equal power at maximum efficiency. The characteristics at several pitch settings and diameter spacings were compared with 2-blade and 4-blade propellers. Tandem propellers were found to have an advantage over single propellers at higher pitch settings.
Date: August 1937
Creator: Lesley, E. P.
Partner: UNT Libraries Government Documents Department
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Energy Loss, Velocity Distribution, and Temperature Distribution for a Baffled Cylinder Model, Special Report

Description: Report discusses the important principles involved in the operation of a baffle for an engine cylinder and how using a correctly designed baffle can improve cooling. The baffle-exit radius and width and exit-duct length were found to be the most important parts of the baffle and a baffle that gave a relatively uniform temperature distribution was designed.
Date: April 1937
Creator: Brevoort, Maurice J.
Partner: UNT Libraries Government Documents Department
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Stability of Castering Wheels for Aircraft Landing Gears, Special Report

Description: In many installations of castering rubber-tired wheels there is a tendency for the wheel to oscillate violently about the spindle axis. This phenomenon, popularly called 'shimmy,' has occurred in some airplane tail wheels and has been corrected in two ways: first by the application of friction in the spindles of the tail wheels; and, second, by locking the wheels while taxiing at high speeds. Shimmy is common with the large wheels used as nose wheels in tricycle landing gears and, since it is i… more
Date: September 1937
Creator: Kantrowitz, Arthur
Partner: UNT Libraries Government Documents Department
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Accelerations in Landing with a Tricycle-Type Landing Gear

Description: "In connection with the application of stable tricycle-type landing gears to transport airplanes, the question arises as to whether certain passengers may not experience relatively great accelerations in an emergency landing. Since the main landing wheels are behind the center of gravity in this type of gear, a hard-braked landing will cause immediate nosing down of the airplane and, when this motion is stopped due to the front wheel striking the ground, there will be some tendency for the rear… more
Date: February 1937
Creator: Jones, Robert T.
Partner: UNT Libraries Government Documents Department
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Notes on Factors Affecting Geometrical Arrangement of Tricycle-Type Landing Gears

Description: The effects of the geometrical arrangement of tricycle landing gears on various characteristics of an airplane equipped with such landing gear is discussed. The characteristics discussed include directional stability, overturning tendencies, steering and ground handling, shimmy, takeoff, and porpoising. The conclusions are summarized in a table.
Date: April 1937
Creator: Wenzinger, Carl J. & Kantrowitz, A. R.
Partner: UNT Libraries Government Documents Department
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The Transition Phase in the Take-Off of an Airplane, Special Report

Description: "An investigation was undertaken to determine the character and importance of the transition phase between the ground run and steady climb in the takeoff of an airplane and the effects of various factors on this phase and on the airborne part of the takeoff as a whole. The information was obtained from a series of step-by-step integrations, which defined the motion of the airplane during the transition and which were based on data derived from actual takeoff tests of a Verville AT airplane. Bot… more
Date: December 1937
Creator: Wetmore, J. W.
Partner: UNT Libraries Government Documents Department
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A Study of Transparent Plastics for use on Aircraft, Special Report

Description: "Various transparent organic plastics, including both commercially available and experimental materials, have been examined to determine their suitability for use as flexible windshields on aircraft, The properties which have been studied include light transmission, haziness, distortion, resistance to weathering, scratch and indentation hardness, impact strength, dimensional stability, resistance to water and various cleaning fluids, bursting strength at normal and low temperatures, and flammab… more
Date: May 12, 1937
Creator: Axilrod, Benjamin M. & Kline, Gordon M.
Partner: UNT Libraries Government Documents Department
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