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Sylphon diaphragms : a method for predicting their performance for purposes of instrument design

Description: Here, the purpose is to show that the characteristic performance of a syphon diaphragm can be predicted from a knowledge of its stiffness and of its dimensions. The proof is based on a mathematical analysis of this type of diaphragm, together with enough experimental data to prove the validity of the assumptions and the sufficiency of the analysis. Equations are developed for the performance of syphons under various conditions of loading, both for concentrated loads and for hydrostatic pressure.
Date: May 1922
Creator: Eaton, H. N. & Keulegan, G. H.
Partner: UNT Libraries Government Documents Department
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Notes on Propeller Design 4: General Proceeding in Design

Description: The choice of the numbers of revolutions and of the diameter, the distribution of thrust, and the values of the constants in the aerodynamical equations of the propeller are discussed.
Date: May 1922
Creator: Munk, Max M.
Partner: UNT Libraries Government Documents Department
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High Altitude Flying

Description: This note investigates the effect of high altitude or low atmospheric pressure upon the operation of an engine and the effect of the low pressure and lack of oxygen and of the very low temperatures upon the pilot and upon the performance of the airplane itself.
Date: May 1924
Creator: King, Paul B. & Carroll, Thomas
Partner: UNT Libraries Government Documents Department
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A method of determining the dimensions and horsepower of an airship for any given performance

Description: A simple and easily applied method of calculating the dimensions and horsepower necessary for an airship to have any given performance is described and illustrated by examples. The method includes means for estimating the changes in performance or in size when modifications or new features are introduced into a design, involving increase or saving in weights, or changes in resistance or propulsive efficiency.
Date: May 1924
Creator: Burgess, C. P.
Partner: UNT Libraries Government Documents Department
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Propeller Design: Practical Application of the Blade Element Theory 1

Description: "This report is the first of a series of four on propeller design and contains a description of the blade elements or modified Drzewiecke theory as used in the Bureau of Aeronautics, U.S. Navy Department. Blade interference corrections are used which were taken from R.& M. NO. 639 of the British Advisory Committee for Aeronautics. The airfoil characteristics used were obtained from tests of model propellers, not from tests of model wings" (p. 1).
Date: May 1926
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department
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Propeller Design - A Simple System Based on Model Propeller Test Data -III

Description: "This report, the third of a series of four, describes a simple system for designing propellers of a standard form. In this report, the system is based on tests of a family of model propellers of standard Navy form, the data from which have been extended by means of calculations to cover the complete range likely to be found in practice. However, it can be worked out for any family having propellers of one general form" (p. 1).
Date: May 1926
Creator: Wieck, Fred E.
Partner: UNT Libraries Government Documents Department
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Propeller Design: Extension of Test Data on a Family of Model Propellers by Means of the Modified Blade Element Theory 2

Description: This report is the second of a series of four on propeller design, and describes the method used to extend the data obtained from tests on a family of thirteen model propellers to include all propellers of the same form likely to be met in practice. This necessitates the development of a method of propeller analysis which when used to calculate the powers and efficiencies gives results which check the tests throughout their range.
Date: May 1926
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department
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Experiments With a Built-In or Fuselage Radiator

Description: "The experiments discussed here were performed to determine whether radiators having similar cooling properties offer less resistance when incorporated into the fuselage, than when the hitherto customary arrangement is employed, with the radiator in the free air current more or less independent of the fuselage. The experiments indicated that the quantity of air flowing through the radiator is greatest when the fuselage and the radiator are separate. However, separate radiators cause more air resistance" (p. 1).
Date: May 1923
Creator: Wieselsberger, C.
Partner: UNT Libraries Government Documents Department
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The Effect of Wind Tunnel Turbulence Upon the Forces Measured on Models

Description: These tests were undertaken to find the effect of turbulence in the air stream upon the lift and drag forces measured on models in the four-foot wind tunnel at the Massachusetts Institute of Technology. Maximum lifts and minimum drags were measured on Gottingen-387 and R.A.F.-15 airfoils, minimum drag on a streamlined strut, and the static pressure gradients for different conditions of turbulence were investigated. The results show that the scale of the turbulence (as defined in this report) has a marked effect upon the measured forces on models tested in the tunnel as well as on the pressure gradient, and it is recommended that further investigation of the phenomena be made with the aid of smoke and small wind vanes.
Date: May 1924
Creator: LePage, W. L. & Nichols, J. T.
Partner: UNT Libraries Government Documents Department
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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
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Influence of Ribs on Strength of Spars

Description: Note presenting an investigation to determine what effect joints connected with brackets, nails, and glue has on the strength of aircraft wing spars. Equations used to determine the results of loading tests are provided.
Date: May 1923
Creator: Ballenstedt, L.
Partner: UNT Libraries Government Documents Department
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Airplane Performance as Influenced by the Use of a Supercharged Engine

Description: "The question of the influence of a supercharged engine on airplane performance is treated here in a first approximation, but one that gives an exact idea of the advantage of supercharging. Considered here is an airplane that climbs first with an ordinary engine, not supercharged, and afterwards climbs with a supercharged engine. The aim is to find the difference of the ceilings reached in the two cases" (p. 1).
Date: May 1920
Creator: de Bothezat, George
Partner: UNT Libraries Government Documents Department
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Relation of Rib Spacing to Stress in Wing Planes

Description: The stress relations to the fabric and the rib consequent upon a change of spacing between ribs in a wing plane are discussed. Considering the wing plane as a static structure, and ignoring the question of aerodynamic efficiency, it appears that the unit stress in the rib and fabric will remain constant for constant p if the linear dimensions of both rib and fabric are increased alike, viz., if wing and fabric remain geometrically similar. Since the bulge and the structural dimensions remain geometrically similar, the whole distended plane remains so, and hence should have the same pressure distribution and efficiency.
Date: May 1920
Creator: Zahm, A. F.
Partner: UNT Libraries Government Documents Department
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N.A.C.A. control position recorder

Description: Report discussing a new instrument is described which is capable of simultaneously recording the position of the three controls of an airplane. The records are taken photographically on a standard N.A.C.A. film drum and the instrument can be quickly installed in any airplane.
Date: May 1922
Creator: Norton, F. H.
Partner: UNT Libraries Government Documents Department
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Notes on the Design of Latticed Columns Subject to Lateral Loads

Description: "No rational column formula has yet been developed which gives results which are sufficiently precise for the design of airplane members, and consequently it is necessary to fall back upon experimental testing. In order to derive the maximum benefit from experiments, however, it is necessary that the experiments be guided by theory. It is the object here to modify existing formulae that may be obtained with a minimum number of tests" (p. 1).
Date: May 1922
Creator: McCarthy, Charles J.
Partner: UNT Libraries Government Documents Department
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Airplane Superchargers

Description: Discussed here are the principles and operation of aircraft engine superchargers used to maintain and increase engine power as aircraft encounter decreases in the density of air as altitude rises. Details are given on the design and operation of the centrifugal compressors. A method is given for calculating the amount of power needed to drive a compressor. The effects of the use of a compressor on fuel system operation and design are discussed. Several specific superchargers that were in operation are described.
Date: May 1921
Creator: Noack, W. G.
Partner: UNT Libraries Government Documents Department
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On a New Type of Wind Tunnel

Description: Discussed here is a new type of wind tunnel, its advantages, the difficulties attendant upon its use, and the special methods required for its operation. The main difference between the new type of wind tunnel and the ones now in operation is the use of a different fluid. The idea is to diminish the effect of viscosity.
Date: May 1921
Creator: Munk, Max
Partner: UNT Libraries Government Documents Department
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Notes on the Theory of the Accelerometer

Description: Report discusses several types of accelerometers and how they function. Methods for reducing error and determining the source of the error, including the best placement for the device, are included.
Date: May 1920
Creator: Warner, E. P.
Partner: UNT Libraries Government Documents Department
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The Problem of the Helicopter

Description: Report discussing some of the issues regarding the design and operation of helicopters and the theoretical basis behind them. Some particular issues covered include propeller blade design, helicopters in forced descent, horizontal travel, and stability and control.
Date: May 1920
Creator: Warner, E. P.
Partner: UNT Libraries Government Documents Department
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British Certificates of Airworthiness

Description: This report details the rules and regulations for obtaining a British airworthiness certificate. Aircraft loading and construction are especially important.
Date: May 1921
Partner: UNT Libraries Government Documents Department
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The Reaction on a Float Bottom When Making Contact With Water at High Speeds

Description: Tests were conducted to investigate the possibility of a serious accident arising from unintentional contact with the water in substantially horizontal flight at high speed. Referring to vector diagrams on Figure 2, it will be seen that a very dangerous condition may arise if the float be allowed to come in contact with the water at high speeds as, for example, when flying at high speed just above the water. The initial diving moment due to suction and drag combined may be great enough to cause the seaplane to nose under before the pilot is able to control the motion.
Date: May 1928
Creator: Richardson, H. C.
Partner: UNT Libraries Government Documents Department
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