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Studies of Basin-Range Structure

Description: From preface: This paper represents the partial fruition of a broad plan to reexamine critically the subject of Basin-Range structure.
Date: 1928
Creator: Gilbert, Grove Karl
Partner: UNT Libraries Government Documents Department

Report of the Twenty-First National Conference on Weights and Measures, 1928

Description: Report of the annual conference on weights and measures, hosted by the U.S. National Bureau of Standards in Washington D.C. It includes conference proceedings, a list of attendees, information about committees and officers, and other reports or commentaries discussed at the meetings.
Date: May 1928
Creator: United States. National Bureau of Standards.
Partner: UNT Libraries Government Documents Department

On the take-off of heavily loaded airplanes

Description: This report examines the take-off conditions of airplanes equipped with tractive propellers, and particularly the more difficult take-off of airplanes heavily loaded per unit of wing area (wing loading) or per unit of engine power (power loading).
Date: November 1, 1928
Creator: Breguet, Louis
Partner: UNT Libraries Government Documents Department

The measurement of pressure through tubes in pressure distribution tests

Description: The tests described in this report were made to determine the error caused by using small tubes to connect orifices on the surface of aircraft to central pressure capsules in making pressure distribution tests. Aluminum tubes of 3/16-inch inside diameter were used to determine this error. Lengths from 20 feet to 226 feet and pressures whose maxima varied from 2 inches to 140 inches of water were used. Single-pressure impulses for which the time of rise of pressure from zero to a maximum varied from 0.25 second to 3 seconds were investigated. The results show that the pressure recorded at the capsule on the far end of the tube lags behind the pressure at the orifice end and experiences also a change in magnitude. For the values used in these tests the time lag and pressure change vary principally with the time of rise of pressure from zero to a maximum and the tube length. Curves are constructed showing the time lag and pressure change. Empirical formulas are also given for computing the time lag. Analysis of pressure distribution tests made on airplanes in flight shows that the recorded pressures are slightly higher than the pressures at the orifice and that the time lag is negligible. The apparent increase in pressure is usually within the experimental error, but in the case of the modern pursuit type of airplane the pressure increase may be 5 per cent. For pressure-distribution tests on airships the analysis shows that the time lag and pressure change may be neglected.
Date: January 1, 1928
Creator: Hemke, Paul E
Partner: UNT Libraries Government Documents Department

A few more mechanical-flight formulas without the aid of polar diagrams

Description: The reliability of the assumption of a parabolic shape of the polar curve is investigated and found satisfactory for all practical purposes. It is further shown that the aerodynamically best possible or "ideal" airplane is produced on this assumption. Lastly, detailed suggestions are given on the possibilities of application of this method of calculation. It especially simplifies the design and evaluation of structural changes and the determination of the limits of technical possibilities. The present report deals only with the relations of the airfoils. The mutual action of the airfoils, engine and propeller will be treated in a subsequent report.
Date: March 1, 1928
Creator: Schrenk, Martin
Partner: UNT Libraries Government Documents Department

Drag of exposed fittings and surface irregularities on airplane fuselages

Description: Measurements of drag were made on fittings taken from a typical fuselage to determine whether the difference between the observed full size fuselage drag and model fuselage drag could be attributed to the effects of fittings and surface irregularities found on the full size fuselage and not on the model. There are wide variations in the drag coefficients for the different fittings. In general those which protrude little from the surface or are well streamlined show very low and almost negligible drag. The measurements show, however, that a large part of the difference between model and full scale test results may be attributed to these fittings.
Date: March 1928
Creator: Wood, Donald H.
Partner: UNT Libraries Government Documents Department

Full scale drag tests on various parts of Sperry Messenger airplane

Description: The drag of a Sperry Messenger airplane with the wings removed, and also the drag of its various component parts, was measured in the 20-foot air stream of the N.A.C.A. propeller research tunnel at air speeds from 50 to 100 m.p.h. It was found that the three-cylinder radial air-cooled engine nearly doubled the drag of the bare fuselage, and the drag of the landing gear was about the same as that of the fuselage and engine combined.
Date: January 1, 1928
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

The gaseous explosive reaction : the effect of inert gases

Description: Attention is called in this report to previous investigations of gaseous explosive reactions carried out under constant volume conditions, where the effect of inert gases on the thermodynamic equilibrium was determined. The advantage of constant pressure methods over those of constant volume as applied to studies of the gaseous explosive reaction is pointed out and the possibility of realizing for this purpose a constant pressure bomb mentioned. The application of constant pressure methods to the study of gaseous explosive reactions, made possible by the use of a constant pressure bomb, led to the discovery of an important kinetic relation connecting the rate of propagation of the zone of explosive reaction within the active gases, with the initial concentrations of those gases: s = K(sub 1)(A)(sup n1)(B)(sup n2)(C)(sup n3)------. By a method analogous to that followed in determining the effect of inert gases on the equilibrium constant K, the present paper records an attempt to determine their kinetic effect upon the expression given above.
Date: January 1, 1928
Creator: Stevens, F W
Partner: UNT Libraries Government Documents Department

Ignition and combustion phenomena in Diesel engines

Description: Evidences were found that neither gasification nor vaporization of the injected fuel occurs before ignition; also that the hydrogen coefficient has no significance. However the knowledge of the ignition point and of the "time lag" is important. After ignition, the combustion proceeds in a series of reactions, the last of which at least are now known.
Date: October 1, 1928
Creator: Sass, F
Partner: UNT Libraries Government Documents Department

Ignition points and combustion reactions in Diesel engines. Part I

Description: The question of whether the fuel should be adapted to the engine or whether it is possible to improve equipment such as carburetors and engines so that as much of the crude oil as possible may be used without further transformation is examined in this report. Various ignition points and fuel mixtures are investigated in this regard.
Date: October 1, 1928
Creator: Tausz, J & Schulte, F
Partner: UNT Libraries Government Documents Department

Helium tables.

Description: These tables are intended to provide a standard method and to facilitate the calculation of the quantity of "Standard Helium" in high pressure containers. The research data and the formulas used in the preparation of the tables were furnished by the Research Laboratory of Physical Chemistry, of the Massachusetts Institute of Technology.
Date: January 1, 1928
Creator: Havill, Clinton H
Partner: UNT Libraries Government Documents Department

Crank case scavenging of a two-stroke-cycle engine

Description: Experiments with a two-stroke-cycle, crank case scavenging engine. Effect of systematic variation of the height of the scavenge and exhaust ports on the scavenging, as determined by gas analysis. The best results were obtained under conditions differing from the usual ones.
Date: January 1, 1928
Creator: Holm, Otto
Partner: UNT Libraries Government Documents Department

Drag and cooling with various forms of cowling for a Whirlwind engine in a cabin fuselage

Description: An investigation on the cowling of radial air-cooled engines was conducted in the 20-foot Propeller Research Tunnel at Langley Field. Cooling and drag tests were made with each form of cowling. The propulsive efficiency was found to be practically the same with all forms of cowling.
Date: November 1, 1928
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

The drag of a J-5 radial air-cooled engine

Description: This note describes tests of the drag due to a Wright "Whirlwind" (J-5) radial air-cooled engine mounted on a cabin type airplane. The tests were made in the 20-foot Propeller Research Tunnel of the National Advisory Committee for Aeronautics. The drag was obtained with three different types of exhaust stacks: Short individual stacks, a circular cross section collector ring, and a streamline cross section collector ring.
Date: July 1, 1928
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

Drag of wings with end plates

Description: In this report a formula for calculating the induced drag of multiplanes with end plates is derived. The frictional drag of the end plates are used, is sufficiently large to increase the efficiency of the wing. Curves showing the reduction of drag for monoplanes and biplanes are constructed; the influence of gap-chord ratio, aspect ratio, and height of end plate are determined for typical cases. The method of obtaining the reduction of drag for a multiplane is described. Comparisons are made of calculated and experimental results obtained in wind tunnel tests with airfoils of various aspect ratios and end plates of various sizes. The agreement between calculated and experimental results is good. Analysis of the experimental results shows that the shape and section of the end plates are important.
Date: January 1, 1928
Creator: Hemke, Paul E
Partner: UNT Libraries Government Documents Department

Determination of propeller deflection by means of static load tests on models

Description: This note describes a simple and inexpensive method for determining the deflection of propeller blades under operating loads. Both the centrifugal force and air force loads are applied statically as a number of concentrated loads by means of weights and wires. Two methods of attaching the wires to the propeller blades have been tested, both giving approximately the same deflections. The method is considered useful for studying the deflections of propellers of different shapes under various operating conditions.
Date: January 1, 1928
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

The C.A.M.S. 54 G.R. transatlantic seaplane (French)

Description: Tested at the end of March, 1928, the C.A.M.S. 54 G.R. was built for the purpose of crossing the Atlantic from Europe by way of the azores. It has a biplane construction with wings mounted above the hull. It is powered by two new series 500 HP. geared Hispano Suiza V type engines.
Date: September 1, 1928
Creator: Ide, John Jay
Partner: UNT Libraries Government Documents Department

The Caproni monoplanes "Ca 97" Italian

Description: The Ca 97 is constructed with wings half overhung, a large fuselage, all metal construction, and can be configured with 1 to 3 engines.
Date: October 1, 1928
Partner: UNT Libraries Government Documents Department

Comments on crankless engine types

Description: This report describes the leading crankless engine types, which have appeared in recent years. These types include: the Mitchell crankless motor car engine and the German Michel engine.
Date: May 1, 1928
Partner: UNT Libraries Government Documents Department

Characteristics of propeller sections tested in the variable density wind tunnel

Description: Tests were carried out in the variable density wind tunnel of the National Advisory Committee for Aeronautics on six airfoil sections used by the Bureau of Aeronautics as propeller sections. The sections were tested at pressures of 1 and 20 atmospheres corresponding to Reynolds numbers of about 170,000 and 3,500,000. The results obtained, besides providing data for the design of propellers, should be of special interest because of the opportunity afforded for the study of scale effect on a family of airfoil sections having different thickness ratios. (author).
Date: January 1, 1928
Creator: Jacobs, Eastman N.
Partner: UNT Libraries Government Documents Department

The cells of giant airplanes

Description: This report presents a discussion of the Rohrbach type of giant airplane. The problems considered are structural drag, wing loading and divided power plants.
Date: September 1, 1928
Creator: Weyl, A R
Partner: UNT Libraries Government Documents Department