Technical Report Archive & Image Library (TRAIL) - 300 Matching Results

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The Inertia Coefficients of an Airship in a Frictionless Fluid

Description: The apparent inertia of an airship hull is examined. The exact solution of the aerodynamical problem is studied for hulls of various shapes with special attention given to the case of an ellipsoidal hull. So that the results for the ellipsoidal hull may be readily adapted to other cases, they are expressed in terms of the area and perimeter of the largest cross section perpendicular to the direction of motion by means of a formula involving a coefficient kappa which varies only slowly when the … more
Date: 1924
Creator: Bateman, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design of Wind Tunnels and Wind Tunnel Propellers, 2

Description: Report presenting a continuation of a previous study in order to supply further data to the designers of wind tunnels. Particular emphasis was placed on the study of directional variation in the wind stream. The results indicated that placing radial vanes directly before the propeller actually increased the efficiency of the tunnel to a considerable extent.
Date: 1921
Creator: Norton, F. H. & Warner, E. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nomenclature for Aeronautics

Description: "This nomenclature for aeronautics was prepared by a special conference on aeronautical nomenclature by the Executive Committee of the National Advisory Committee for Aeronautics at a meeting held August 11, 1933. This publication supersedes all previous publications of the committee on this subject. The purpose of the committee in the preparation and publication of this report is to secure uniformity in the official documents of the government and, as far as possible, in technical and other co… more
Date: 1924
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Aerodynamic theory and tests of strut forms 2

Description: This report presents the second of two studies under the same title. In this part five theoretical struts are developed from distributed sources and sinks and constructed for pressure and resistance tests in a wind tunnel. The surface pressures for symmetrical inviscid flow are computed for each strut from theory and compared with those found by experiment. The theoretical and experimental pressures are found to agree quantitatively near the bow, only qualitatively over the suction range, the e… more
Date: May 1929
Creator: Smith, R. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tests of large airfoils in the propeller research tunnel, including two with corrugated surfaces

Description: This report gives the results of the tests of seven 2 by 12 foot airfoils (Clark Y, smooth and corrugated, Gottingen 398, N.A.C.A. M-6, and N.A.C.A. 84). The tests were made in the propeller research tunnel of the National Advisory Committee for Aeronautics at Reynolds numbers up to 2,000,000. The Clark Y airfoil was tested with three degrees of surface smoothness. Corrugating the surface causes a flattening of the lift curve at the burble point and an increase in drag at small flying angles.
Date: May 24, 1929
Creator: Wood, Donald H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Gaseous Explosive Reaction at Constant Pressure: The Reaction Order and Reaction Rate

Description: The data given in this report covers the explosive limits of hydrocarbon fuels. Incidental to the purpose of the investigation here reported, the explosive limits will be found to be expressed for the condition of constant pressure, in the fundamental terms of concentrations (partial pressures) of fuel and oxygen.
Date: May 9, 1929
Creator: Stevens, F. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Effect of Reduction Gearing on Propeller-Body Interference as Shown by Full-Scale Wind-Tunnel Tests

Description: This report presents the results of full-scale tests made on a 10-foot 5-inch propeller on a geared J-5 engine and also on a similar 8-foot 11-inch propeller on a direct-drive J-5 engine. Each propeller was tested at two different pitch settings, and with a large and a small fuselage. The investigation was made in such a manner that the propeller-body interference factors were isolated, and it was found that, considering this interference only, the geared propellers had an appreciable advantage… more
Date: March 20, 1929
Creator: Weick, Fred E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Full-Scale Wind-Tunnel Tests With a Series of Propellers of Different Diameters on a Single Fuselage

Description: "Aerodynamic tests were made with four geometrically similar metal propellers of different diameters, on a Wright "Whirlwind" J-5 engine in an open cockpit fuselage. The results show little difference in the characteristics of the various propellers, the only one of any importance being an increase of efficiency of the order of 1 per cent for a 5 per cent increase of diameter, within the range of the tests" (p. 107).
Date: March 12, 1929
Creator: Weick, Fred E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of turbulence in wind-tunnel measurements

Description: This paper gives some quantitative measurements of wind tunnel turbulence and its effect on the air resistance of spheres and airship models, measurements made possible by the hot wire anemometer and associated apparatus in its original form was described in Technical Report no. 320 and some modifications are presented in an appendix to the present paper. One important result of the investigation is a curve by means of which measurements of the air resistance of spheres can be interpreted to gi… more
Date: August 20, 1929
Creator: Dryden, H. L. & Kuethe, A. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of variation of chord and span of ailerons on rolling and yawing moments at several angles of pitch

Description: This report presents the results of an extension to higher angles of attack of the investigation of the rolling and yawing moments due to ailerons of various chords and spans on two airfoils having the Clark Y and U. S. A. 27 wings. The measurements were made at various angles of pitch but at zero angle of roll and yaw, the wing chord being set at an angle of +4 degrees to the fuselage axis. In the case of the Clark Y airfoil the measurements have been extended to a pitch angle of 40 degrees, u… more
Date: October 7, 1929
Creator: Heald, R. H.; Strother, D. H. & Monish, B. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Design of Plywood Webs for Airplane Wing Beams

Description: This report deals with the design of plywood webs for wooden box beams to obtain maximum strength per unit weight. A method of arriving at the most efficient and economical web thickness, and hence the most suitable unit shear stress, is presented and working stresses in shear for various types of webs and species of plywood are given. The questions of diaphragm spacing and required glue area between the webs and flange are also discussed.
Date: November 27, 1929
Creator: Trayer, George W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Water pressure distribution on a flying boat hull

Description: This is the third in a series of investigations of the water pressures on seaplane floats and hulls, and completes the present program. It consisted of determining the water pressures and accelerations on a Curtiss H-16 flying boat during landing and taxiing maneuvers in smooth and rough water.
Date: December 4, 1929
Creator: Thompson, F. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Working Charts for the Selection of Aluminum Alloy Propellers of a Standard Form to Operate With Various Aircraft Engines and Bodies

Description: "Working charts are given for the convenient selection of aluminum alloy propellers of a standard form, to operate in connection with six different engine-fuselage combinations. The charts have been prepared from full-scale test data obtained in the 20-foot propeller research tunnel of the National Advisory Committee for Aeronautics. An example is also given showing the use of the charts" (p. 3).
Date: March 25, 1929
Creator: Weick, Fred E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Full-scale wind-tunnel tests of a propeller with the diameter changed by cutting off the blade tips

Description: Tests were conducted in order to determine how the characteristics of a propeller are affected by cutting off the tips. The diameter of a standard 10-foot metal propeller was changed successively to 9 feet 6 inches, 9 feet 0 inches, 8 feet 6 inches, and 8 feet 0 inches. Each propeller thus formed was tested at four pitch settings using an open cockpit fuselage and a D-12 engine. A small loss in propulsive efficiency is indicated. Examples are given showing the application of the results to prac… more
Date: December 10, 1929
Creator: Wood, Donald H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Large-scale aerodynamic characteristics of airfoils as tested in the variable density wind tunnel

Description: From Summary: "In order to give the large-scale characteristics of a variety of airfoils in a form which will be of maximum value, both for airplane design and for the study of airfoil characteristics, a collection has been made of the results of airfoil tests made at full-scale values of the Reynolds number in the variable density wind tunnel of the National Advisory Committee for Aeronautics. They have been corrected for tunnel wall interference and are presented not only in the conventional … more
Date: October 21, 1929
Creator: Jacobs, Eastman N. & Anderson, Raymond F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Full-Scale Wind-Tunnel Tests on Several Metal Propellers Having Different Blade Forms

Description: "This report gives the full-scale aerodynamic characteristics of five different aluminum alloy propellers having four different blade forms. They were tested on an open cockpit fuselage with a radial air-cooled engine having conventional cowling. The results show that (1) the differences in propulsive efficiency due to the differences in blade form were small; (2) the form with the thinnest airfoil sections had the highest efficiency; (3) it is advantageous as regards propulsive efficiency for … more
Date: March 18, 1929
Creator: Weick, Fred E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Aerodynamic theory and test of strut forms. Part I

Description: This report presents the first part of a two part study made under this title. In this part the symmetrical inviscid flow about an empirical strut of high service merit is found by both the Rankine and the Joukowsky methods. The results can be made to agree as closely as wished. Theoretical stream surfaces as well as surfaces of constant speed and pressure in the fluid about the strut are found. The surface pressure computed from the two theories agrees well with the measured pressure on the fo… more
Date: May 1928
Creator: Smith, R. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The prediction of airfoil characteristics

Description: This report describes and develops methods by which the aerodynamic characteristics of an airfoil may be calculated with sufficient accuracy for use in airplane design. These methods for prediction are based on the present aerodynamic theory and on empirical formulas derived from data obtained in the N. A. C. A. variable density wind tunnel at a Reynolds number corresponding approximately to full scale. (author).
Date: March 14, 1928
Creator: Higgins, George J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Drag and Cooling With Various Forms of Cowling for A "Whirlwind" Radial Air-Cooled Engine - 1

Description: "This report presents the results of an investigation undertaken in the 20-foot Propeller Research Tunnel at Langley Field on the cowling of radial air-cooled engines. A portion of the investigation has been completed, in which several forms and degrees of cowling were tested on Wright "Whirlwind" J-5 engine mounted in the nose of a cabin fuselage. The cowlings varied from the one extreme of an entirely exposed engine to the other in which the engine was entirely inclosed. Cooling tests were ma… more
Date: October 5, 1928
Creator: Weick, Fred E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Drag and Cooling With Various Forms of Cowling for A "Whirlwind" Radial Air-Cooled Engine - 2

Description: "This report gives the results of the second portion of an investigation in the twenty-foot Propeller Research Tunnel of the National Advisory Committee for Aeronautics, on the cowling and cooling of a "Whirlwind" J-5 radial air-cooled engine. The first portion pertains to tests with a cabin fuselage. This report covers tests with several forms of cowling, including conventional types, individual fairings behind the cylinders, individual hoods over the over the cylinders, and the new N. A. C. A… more
Date: December 17, 1928
Creator: Weick, Fred E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tables for pressure of air on coming to rest from various speeds

Description: From Summary: "In Technical Report no. 247 of the National Advisory Committee for Aeronautics theoretical formulas are given from which was computed a table for the pressure of air on coming to rest from various speeds, such as those of aircraft and propeller blades. In that report, the table gave incompressible and adiabatic stop pressures of air for even-speed intervals in miles per hour and for some even-speed intervals in knots per hour. Table II of the present report extends the above-ment… more
Date: December 17, 1928
Creator: Zahm, A. F. & Louden, F. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Speed and deceleration trials of U.S.S. Los Angeles

Description: From Summary: "The trials reported in this report were instigated by the Bureau of Aeronautics of the Navy Department for the purpose of determining accurately the speed and resistance of the U. S. S. "Los Angeles" with and without water recovery apparatus, and to clear up the apparent discrepancies between the speed attained in service and in the original trials in Germany. The trials proved very conclusively that the water recovery apparatus increases the resistance about 20 per cent, which i… more
Date: June 12, 1928
Creator: De France, S. J. & Burgess, C. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The measurement of fluctuations of air speed by the hot-wire anemometer

Description: "The hot-wire anemometer suggests itself as a promising method for measuring the fluctuating air velocities found in turbulent flow. The only obstacle is the presence of a lag due to the limited energy input which makes even a fairly small wire incapable of following rapid fluctuations with accuracy. This paper gives the theory of the lag and describes an experimental arrangement for compensating for the lag for frequencies up to 100 or more per second when the amplitude of the fluctuation is n… more
Date: January 8, 1929
Creator: Dryden, H. L. & Kuethe, A. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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