Technical Report Archive and Image Library (TRAIL) - 1,526 Matching Results

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Airplane drag

Description: It has been less well understood that the induced drag (or, better said, the undesired increase in the induced drag as compared with the theoretical minimum calculated by Prandtl) plays a decisive role in the process of taking off and therefore in the requisite engine power. This paper seeks to clarify the induced drag.
Date: December 1929
Creator: Topfer, Carl
Partner: UNT Libraries Government Documents Department

The balance of moments and the static longitudinal stability of airplanes

Description: A nomogram is developed which renders it possible by drawing a few lines, to determine: the location of the center of gravity for zero wing and tail moments; the longitudinal dihedral angle; the tail coefficient F(sub h) iota/F(sub t). Moreover there is no difficulty in determining the magnitude of the restoring moment or of the unstable moment.
Date: December 1, 1929
Creator: Muller, Horst
Partner: UNT Libraries Government Documents Department

Calculation of the pressures on aircraft engine bearings

Description: For aircraft engines the three principal operating conditions are idling speed, cruising speed, and diving with the engine stopped. In what follows, we will discuss a method which affords a good idea of the course of pressure for the above mentioned operating conditions. The pressures produced in the driving gear are of three kinds; namely, the pressure due to gases, the pressure due to the inertia of the rotating masses, and the pressure due to the inertia of the reciprocating masses.
Date: December 1, 1929
Creator: Steigenberger, O
Partner: UNT Libraries Government Documents Department

Contribution to the aileron theory

Description: In an attempt to treat theoretically the effect of ailerons, difficulty arises because an aileron may begin at any point of the wing. Hence the question arises as to how the transition of the lift distribution proceeds at such a point, since the effect of the aileron (i.e., the moment generated about the longitudinal axis) depends largely on this distribution. In order to answer this question regarding the lift distribution during irregular variations in the angle of attack at first independently of other influences, especially those of the wing tips, we have taken as the basis of the following theoretical discussion a wing of infinite span and constant chord which exhibits at one point an irregular variation in the angle of attack. As regards the mathematical treatment, we will first consider a wing with periodically recurring angle of attack.
Date: December 1, 1929
Creator: Betz, A & Petersohn, E
Partner: UNT Libraries Government Documents Department

Some effects of air flow on the penetration and distribution of oil sprays

Description: Tests were made to determine the effects of air flow on the characteristics of fuel sprays from fuel injection valves. Curves and photographs are presented showing the airflow throughout the chamber and the effects of the air flow on the fuel spray characteristics. It was found that the moving air had little effect on the spray penetration except with the 0.006 inch orifice. The moving air did, however, affect the oil particles on the outside of the spray cone. After spray cut-off, the air flow rapidly distributed the atomized fuel throughout the spray chamber.
Date: December 1, 1929
Creator: Rothrock, A. M. & Beardsley, E. G.
Partner: UNT Libraries Government Documents Department

Wind tunnel pressure distribution tests on a series of biplane wing models Part III : effects of charges in various combinations of stagger, gap, sweepback, and decalage

Description: A concept for the calculation of the vortex lift of sharp-edge delta wings is presented and compared with experimental data. The concept is based on an analogy between the vortex lift and the leading-edge suction associated with the potential flow about the leading edge. This concept, when combined with potential-flow theory modified to include the nonlinearities associated with the exact boundary condition and the loss of the lift component of the leading-edge suction, provides excellent prediction of the total lift for a wide range of delta wings up to angles of attack of 20 degrees or greater.
Date: December 1, 1929
Creator: Knight, Montgomery & Noyes, Richard W
Partner: UNT Libraries Government Documents Department

Cantilever Wings for Modern Aircraft: Some Aspects of Cantilever Wing Construction with Special Reference to Weight and Torsional Stiffness

Description: In the foregoing remarks I have made an attempt to touch on some of the structural problems met with in cantilever wings, and dealt rather fully with a certain type of single-spar construction. The experimental test wing was a first attempt to demonstrate the principles of this departure from orthodox methods. The result was a wing both torsionally stiff and of light weight - lighter than a corresponding biplane construction.
Date: November 1, 1929
Creator: Stieger, H. J.
Partner: UNT Libraries Government Documents Department

The effect of fuel consumption on cylinder temperatures and performance of a cowled Wright J-5 engine

Description: Given here are the results of tests made to determine the effect of fuel consumption on the cylinder temperatures and the performance of a cowled Wright J-5 engine. The results of these tests indicate that enriching the mixture by increasing the carburetor size results in a reduction in cylinder head and barrel temperatures. The cylinders shielded by the magnetos or the points on the cylinder that do not receive a free flow of cooling air increase most rapidly in temperature as the mixture is leaned. A free flow of air past the cylinders is essential for satisfactory operation on a lean mixture. The results of these tests show that the Wright J-5 engine can withstand severe temperatures for short periods of operation. The test results also show to what extent destructive temperatures may be avoided by enriching the mixture.
Date: November 1, 1929
Creator: Schey, Oscar W
Partner: UNT Libraries Government Documents Department

Mathematical and experimental investigation of heat control and power increase in air-cooled aircraft engines

Description: In order to understand the numerical relations between the air velocity, temperature of the cylinder walls, heat dissipation, cylinder dimensions and type of construction an experimental plant was installed in the Siemens and Halske laboratory. The experimental cylinder was exposed to the air stream of a wind tunnel. The compression chamber was heated by an electrically heated oil bath kept constantly in motion by a stirrer. The wall temperatures were measured by thermocouples. The air stream was produced a seven-watt blower. The air flowed through a current rectifier (honeycomb), diffuser, air chamber with quieting sieves and a nozzle.
Date: November 1929
Creator: Gosslau, F
Partner: UNT Libraries Government Documents Department

Some studies on the aerodynamic effect of the gap between airplane wings and fuselages

Description: The general result indicated by this study is that if desirable from any viewpoint the gap between wing and fuselage may be closed without detrimental aerodynamic effects, and with a given monoplane there is less drag if the wing is directly on top of the fuselage than if it is parasol.
Date: November 1, 1929
Creator: Ober, Shatswell
Partner: UNT Libraries Government Documents Department

Technical details in the structural development of Rohrbach seaplanes

Description: The recent trial flights and acceptance tests of the Rohrbach "Romar," the largest seaplane in the world, have yielded results fully confirming the principles followed in its development. Its take-off weight of 19,000 kg, its beating the world record for raising the greatest useful load to 2000 m by almost 2500 kg and its remarkable showing in the seaworthiness tests are the results of intelligent researches, the guiding principles of which are briefly set forth in this article.
Date: November 1, 1929
Creator: Mathias, Gotthold & Holzapfel, Adolf
Partner: UNT Libraries Government Documents Department

Unsymmetrical forces in an airplane cell

Description: This paper calls attention to the desirability of expanding airplane building regulations to include proof of safety for cases of unsymmetrical loading, at least in the structural members which are thereby specially stressed.
Date: November 1, 1929
Creator: Vogt, R
Partner: UNT Libraries Government Documents Department

The A. B. Flygindustri "K 37" (Swedish Junkers) : a low-wing all-metal military airplane

Description: Report discusses the characteristics of the K 37 all-metal long-wing monoplane and its use for long-distance scouting, as a day bomber, and as a heavy fighting airplane. Its engines, climbing capacity, action radius, bombing installation, fuselage, controls, and landing gear are explored in depth.
Date: October 1929
Partner: UNT Libraries Government Documents Department

The effect of the wings of single engine airplanes on propulsive efficiency as shown by full scale wind tunnel tests

Description: An investigation was conducted to determine the effect of the wings on propulsive efficiency. The wings are shown to cause a reduction of 1 percent to 3 percent in propulsive efficiency, which is about the same for monoplane as well as biplane wings.
Date: October 1, 1929
Creator: Weick, Fred E. & Wood, Donald H.
Partner: UNT Libraries Government Documents Department

Experiments with a wing model from which the boundary is removed by suction

Description: The present report deals with a series of tests made for the purpose of improving flow conditions about wings by applying the suction principle (increase of the lift coefficient and reduction of the drag about very thick wing sections). Though not conclusive, the report contains interesting results.
Date: October 1, 1929
Creator: Schrenk, Oskar
Partner: UNT Libraries Government Documents Department

Fire prevention on airplanes. Part I

Description: Various methods for preventing fires in airplanes are presented with most efforts centering around prevention of backfires, new engine and carburetor designs, as well as investigations on different types of fuels.
Date: October 1, 1929
Creator: Sabatier, J
Partner: UNT Libraries Government Documents Department

Fire prevention on airplanes. Part II

Description: This part of the report presents a detailed examination of spark prevention, fire extinguishers, and fuel tank location and design. A continued program of investigations and research is also proposed.
Date: October 1929
Creator: Sabatier, J
Partner: UNT Libraries Government Documents Department

Handley Page metal construction

Description: In this report Handley Page construction techniques are shown such as: solid-drawn tubular duralumin spars are used in the stabilizer; plain channel sections are used extensively for minor components; and the manner of assembling them into a stabilizer compression strut is shown.
Date: October 1, 1929
Partner: UNT Libraries Government Documents Department