Technical Report Archive and Image Library (TRAIL) - 119 Matching Results

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The Estimation of Airplane Performance From Wind Tunnel Tests on Conventional Airplane Models

Description: Calculations of the magnitude of the correction factors and the range of their variations for wind tunnel models used in making aircraft performance predictions were made for 23 wind tunnel models. Calculated performances were compared with those actually determined for such airplanes as have been built and put through flight test. Except as otherwise noted, all the models have interplane struts and diagonal struts formed to streamwise shape. Wires were omitted in all cases. All the models were about 18 inches in span and were tested in a 4-foot wind tunnel. Results are given in tabular form.
Date: May 1925
Creator: Warner, Edward P. & Ober, Shatswell
Partner: UNT Libraries Government Documents Department

The Drift of an Aircraft Guided Towards It's Destination by Directional Receiving of Radio Signals Transmitted From the Ground

Description: Following a curved path increases the distance to be flown, and a type of radio navigation that forces the adoption of such a path is therefore less efficient than one that marks out a definite straight line between the point of departure and the intended destination, and holds the airplane to that line. To determine the loss of efficiency resulting from curvature of the path, calculations were made for two particular cases by the method of step-by-step integration. The calculations were based on the assumption that the pilot makes straightforward use of his radio for navigation and makes no allowance for drift.
Date: June 1925
Creator: Warner, Edward P.
Partner: UNT Libraries Government Documents Department

The Effect of Changes in Compression Ratio Upon Engine Performance

Description: "This report is based upon engine tests made at the Bureau of Standards during 1920, 1921, 1922, and 1923. The majority of these tests were of aviation engines and were made in the Altitude Laboratory. For a small portion of the work a single cylinder experimental engine was used. This, however, was operated only at sea-level pressures. The report shows that an increase in break horsepower and a decrease in the pounds of fuel used per brake horsepower hour usually results from an increase in compression ratio" (p. 399).
Date: 1925
Creator: Sparrow, Stanwood W.
Partner: UNT Libraries Government Documents Department

European Commercial Aeronautics

Description: "During the months of June to September, 1924, I personally visited the principal airports of Europe and traveled as a passenger some 6500 air miles on English, French, Romanian, Polish, German and Dutch air lines in order to investigate the development of commercial aviation abroad. The results of the investigation are embodied in a series of reports, of which a summary of the general findings is given below" (p. 1).
Date: May 1925
Creator: Van Zandt, J. Parker
Partner: UNT Libraries Government Documents Department

Wire Suspensions in Wind Tunnel Experiments

Description: The elimination of the rigid supports for models and their replacement by wires constitute a great improvement by rendering negligible the interactions of support. There are disadvantages to wire, namely, the aerodynamic resistance is very large and their use is rather difficult because the whole suspension lacks rigidity and easily becomes distorted. We will here investigate the nature of these distortions, evaluate the errors they entail and describe the methods for taking account of or avoiding them.
Date: December 1925
Creator: Kerneis, Jean
Partner: UNT Libraries Government Documents Department

An Altitude Chamber for the Study and Calibration of Aeronautical Instruments

Description: "The design and construction of an altitude chamber, in which both pressure and temperature can be varied independently, was carried out by the NACA at the Langley Memorial Aeronautical Laboratory for the purpose of studying the effects of temperature and pressure on aeronautical research instruments. Temperatures from +20c to -50c are obtained by the expansion of CO2from standard containers. The chamber can be used for the calibration of research instruments under altitude conditions simulating those up to 45,000 feet" (p. 1).
Date: November 1925
Creator: Reid, H. J. E. & Kirchner, Otto E.
Partner: UNT Libraries Government Documents Department

Potential Flow in Engine Valves

Description: "The extensive applicability of the hydrodynamic theory to the problems of engine construction is clearly shown in the following attempt to determine by exact methods the nature of the flow in valves under variously restricted conditions. Observation shows that two principal kinds of flow occur in simple flat-seated valves. For small valve lifts, the flow is along the horizontal wall and is therefore deflected 90 degrees, but for greater valve lifts the flow separates and forms a free stream, whose angle of deflection naturally increases with increasing lift" (p. 1).
Date: December 1925
Creator: Eck, Bruno
Partner: UNT Libraries Government Documents Department

Light Aeroplane Engine Development

Description: "It has frequently been stated and written that in order to popularize light aircraft the first essential is the production of a reliable engine capable of being easily maintained and having a long life, at the same time selling at a low figure. It is desired to point out the difficulties in the way of realizing this ideal before remarking on the claims of the various types for adoption" (p. 1).
Date: April 1925
Creator: Fell, L. F. R.
Partner: UNT Libraries Government Documents Department

Model Tests With a Systematic Series of 27 Wing Sections at Full Reynolds Number

Description: "A systematic series of 27 wing sections, characterized by a small travel of the center or pressure, have been investigated at 20 atmospheres pressure in the variable density wind tunnel of the National Advisory Committee for Aeronautics. The results are consistent with each other, and indicate that for such "stable" sections a small effective camber, a small effective S-shape and a thickness of 8 to 12 per cent lead to good aerodynamic properties" (p. 3).
Date: 1925
Creator: Munk, Max M. & Miller, Elton W.
Partner: UNT Libraries Government Documents Department

Correcting Horsepower Measurements to a Standard Temperature

Description: This report discusses the relation between the temperature of the air at the entrance to the carburetor and the power developed by the engine. Its scope is limited to a consideration of the range of temperatures likely to result from changes of season, locality, or altitude, since its primary aim is the finding of a satisfactory basis for correcting power measurements to a standard temperature. From the results of over 1,600 tests it is concluded that if calculations be based on the assumption that the indicated horsepower of an engine varies inversely as the square root of the absolute temperature of the carburetor air the values obtained will check closely experimental measurements.
Date: 1925
Creator: Sparrow, Stanwood W.
Partner: UNT Libraries Government Documents Department

Hulls for Large Seaplanes

Description: "In reality, the principle of similitude is not applicable to the hulls, the designing of which increases in difficulty with increasing size of the seaplanes. In order to formulate, at least in a general way, the basic principles of calculation, we must first summarize the essential characteristics of a hull with reference to its gradual enlargement. In this study, we will disregard hulls with wing stubs, as being inapplicable to large seaplanes" (p. 2).
Date: January 1925
Creator: Magaldi, Giulio
Partner: UNT Libraries Government Documents Department

Computation of Cantilever Airplane Wings

Description: The purpose of this treatise is, first of all, the determination of the effect of variously loaded spars on one another, since the neglect of this effect would present an economically very unfavorable computation method. The system of spars and cross-bars alone (whether solid or built-up) does not matter at first, the original assumption being that the spars are rigidly braced by the cross-bars.
Date: July 1925
Creator: Thalau, K.
Partner: UNT Libraries Government Documents Department

Determination and Classification of the Aerodynamic Properties of Wing Sections

Description: The following note, prepared for the NACA, contains several remarks on the possible improvement of the experimental determination of the aerodynamic properties of wing sections. It shows how errors of observation can subsequently be partially eliminated, and how the computation of the maxima or minima of aerodynamic characteristics can be much improved.
Date: September 1925
Creator: Munk, Max M.
Partner: UNT Libraries Government Documents Department

Determination of Ignition Points of Liquid Fuels Under Pressure

Description: Two series of experiments were tried, in order to determine the ignition point at any desired pressure, the first series at constant and the second at varying pressure. The results differ greatly and indicate that testing under pressure, in the investigation of liquid fuels, can be done best in the laboratory and that the determination of the ignition points in an open vessel furnishes no certain indication of the behavior of the fuel in the engine.
Date: January 1925
Creator: Tausz, J. & Schulte, F.
Partner: UNT Libraries Government Documents Department

Determination of the Lift and Drag Characteristics of an Airplane in Flight

Description: Flight tests to determine lift and drag characteristics are discussed. A review is given of the fundamental principles on which the tests are based and on the forces acting on an airplane in the various conditions of steady flight. Glide with and without propeller thrust and the relation between angle of attack and the indicated airspeed for different conditions of steady flight are discussed. The glide test procedure and the problem of the propeller are discussed.
Date: August 1925
Creator: Green, Maurice W.
Partner: UNT Libraries Government Documents Department

Royal Aero Club Light Aeroplane Competition

Description: Memorandum describing the results of the Royal Aero Club light airplane competition and some of the history surrounding the event. A list of the planes that participated and an analysis of the performance of the various aircraft are provided.
Date: January 1925
Creator: Buchanan, J. S.
Partner: UNT Libraries Government Documents Department

Schütte-Lanz Airship Projects After the War

Description: The stressing of an airship depends on three nonuniformly distributed forces: air forces; the distribution of acceleration forces; and how the air pressure is distributed on the hull. This report examines the stresses and comes to conclusions on the size of airships.
Date: October 1925
Creator: Weiss, Georg
Partner: UNT Libraries Government Documents Department

Pressure Distribution Over the Wings of an MB-3 Airplane in Flight

Description: "This investigation was carried out to determine the distribution of load over the wings of a high speed airplane under all conditions of flight. In particular it was desired to find the pressure distribution during level flight, over the portions of the wings in the slipstream and, during violent maneuvers, over the entire wing surface. The method used consisted in connecting a number of holes in the surface of the wings to recording multiple manometers mounted in the fuselage of the airplane. In this way simultaneous records could be taken on all of the holes for any desired length of time" (p. 179).
Date: 1925
Creator: Norton, F. H.
Partner: UNT Libraries Government Documents Department