UNT Libraries Government Documents Department - 28 Matching Results

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The Avro "Avian" Airplane : 65 HP. Armstrong-Siddeley "Genet" engine

Description: The Avro Avian, designed by Mr. Chadwick of A.V. Roe & Co., Ltd. has a very low structural weight (estimated at 750 lbs. empty) but with sufficient structural integrity to be eligible of an "Aerobatics" certificate from the British Air Ministry. It can be configured as a monoplane, or a biplane with seaplane floats. It is designed for economical production.
Date: October 1, 1926

Calculation of tubular radiators of the automobile type

Description: We propose to show how to calculate the cooling capacity of all radiators through which the air flows in separate treamlets, whether enclosed in actual tubes or not and whatever cross-sectional shape the tubes may have. The first part will give the fundamental principles for calculating velocity of air in the tubes and the heat exchange by radiation, conduction and convection, and show, by examples, the agreement of the calculation with experiments. In the second part, the effect of the dimensions and conditions of operation on the heat exchange will be systematically investigated.
Date: January 1, 1926
Creator: Richter, L.

Inertia Factors of Ellipsoids for Use in Airship Design

Description: This report is based on a study made by the writer as a member of the Special Committee on Design of Army Semirigid Airship RS-1 appointed by the National Advisory Committee for Aeronautics. The increasing interest in airships has made the problem of the potential flow of a fluid about an ellipsoid of considerable practical importance. In 1833 George Green, in discussing the effect of the surrounding medium upon the period of a pendulum, derived three elliptic integrals, in terms of which practically all the characteristics of this type of motion can be expressed. The theory of this type of motion is very fully given by Horace Lamb in his "Hydrodynamics," and applications to the theory of airships by many other writers. Tables of the inertia coefficients derived from these integrals are available for the most important special cases. These tables are adequate for most purposes, but occasionally it is desirable to know the values of these integrals in other cases where tabulated values are not available. For this reason it seems worth while to assemble a collection of formulae which would enable them to be computed directly from standard tables of elliptic integrals, circular and hyperbolic functions and logarithms without the need of intermediate transformations. Some of the formulae for special cases (elliptic cylinder, prolate spheroid, oblate spheroid, etc.) have been published before, but the general forms and some special cases have not been found in previous publications. (author).
Date: January 1, 1926
Creator: Tuckerman, L. B.

Kirsten-Boeing propeller

Description: The advantages of the Kirsten-Boeing propeller consist essentially in the adjustability of the thrust in any desired direction, in the plane perpendicular to the axis of rotation of the system, and in its high efficiency. The propeller, which greatly resembles the paddle wheels used on river steamers, differs fundamentally from the latter, in that all the blades work simultaneously in the fluid medium (air or water).
Date: February 1, 1926
Creator: Sachse, H

Metal airplane construction

Description: It has long been thought that metal construction of airplanes would involve an increase in weight as compared with wood construction. Recent experience has shown that such is not the case. This report describes the materials used, treatment of, and characteristics of metal airplane construction.
Date: May 1, 1926

Pressure Distribution on the C-7 Airship

Description: This investigation was made for the purpose of determining the aerodynamic pressure distribution encountered on a "C" class airship in flight. It was conducted in two parts: (a) tests on the tail surfaces in which the pressures at 201 points were measured and (b) tests on the envelope in which 190 points were used, both tests being made under as nearly identical flight conditions as possible, so that the results could be combined and the pressure distribution over the entire airship obtained.
Date: January 1, 1926
Creator: Crowley, J. W., Jr. & Defrance, S. J.

Recent developments in the construction and operation of all-metal airplanes

Description: Experiments on the effect of atmosphere and of sea water on the building materials employed by us have been carried on for years in the North Sea with the aid of the Hamburg Naval Observatory. Parallel experiments are being made at the Pisa Naval Observatory in the Mediterranean Sea. Metal sheets, sections, assemblies and experimental floats are being exposed to the action of the elements. Different construction techniques are discussed and a variety of specific airplanes are presented which incorporate some of the new thinking.
Date: September 1, 1926
Creator: Dornier, C

A resume of the advances in theoretical aeronautics made by Max M. Munk

Description: In order to apply profitably the mathematical methods of hydrodynamics to aeronautical problems, it is necessary to make simplifications in the physical conditions of the latter. To begin with, it is allowable in many problems, as Prandtl has so successfully shown, to treat the air as having constant density and as free of viscosity. But this is not sufficient. It is also necessary to specify certain shapes for the solid bodies whose motion through the air is discussed, shapes suggested by the actual solids - airships or airfoils - it is true, but so chosen that they lead to solvable problems. In a valuable paper presented by Dr. Max M. Munk, of the National Advisory Committee for Aeronautics, Washington, to the Delft Conference in April, 1924, these necessary simplifying assumptions are discussed in detail. It is the purpose of the present paper to present in as simple a manner as possible some of the interesting results obtained by Dr. Munk's methods.
Date: January 1, 1926
Creator: Ames, Joseph S

Some aspects of the comparison of model and full-scale tests

Description: This paper was delivered before the Royal Aeronautical Society as the 1925 Wilbur Wright Memorial lecture. It treats the subject of scale effect from the standpoint of the engineer rather than the physicist, in that it shows what compromises are necessary to secure satisfactory engineering model test data and how these test data compare with full scale or with theoretical values. The paper consists essentially of three parts: (1) a brief exposition of the theory of dynamic similarity, (2) application of the theory to airplane model tests, illustrated by test data on airfoils from the National Advisory Committee for Aeronautics variable-density wind tunnel, and (3) application of the theory to propeller testing, illustrated by comparisons of model and full-scale results.
Date: January 1, 1926
Creator: Taylor, D W

Steam Power Plants in Aircraft

Description: The employment of steam power plants in aircraft has been frequently proposed. Arguments pro and con have appeared in many journals. It is the purpose of this paper to make a brief analysis of the proposal from the broad general viewpoint of aircraft power plants. Any such analysis may be general or detailed.
Date: June 1, 1926
Creator: Wilson, E. E.

Tail planes

Description: This report presents methods by which the cells of large commercial airplanes may be reduced. The tail of large airplanes represent an area where considerable improvement in weight and size reduction can be attained.
Date: August 1, 1926
Creator: Constantin, L

Take-off distance for airplanes

Description: There are two principal ways in which the total take-off distance (taxying plus hovering plus the first part of the climb) can be reduced to a minimum. These are: 1) taxying and hovering until the maximum speed has been attained close to the ground and then changing to a steep rapid climb; 2) lifting the airplane from the ground as soon as possible and then climbing at a relatively large angle of attack. These cases, as well as all the other conceivable combinations, can be expressed with a single basic formula, which is derived from the energy equation for rectilinear flight.
Date: September 1, 1926
Creator: Proll, A

Test of a model propeller with symmetrical blade sections

Description: This report, prepared at the request of NACA, gives the results of tests on a model propeller having blade sections with form of Gottingen airfoil no. 409. The model is shown to have a dynamic pitch practically equal to the nominal or geometrical pitch, and a somewhat higher efficiency but lower coefficient than would be expected of a propeller of more conventional sections.
Date: September 1, 1926
Creator: Lesley, E. P.