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General Theory of Aerodynamic Instability and the Mechanism of Flutter

Description: "The aerodynamic forces on an oscillating airfoil or airfoil-aileron combination of three independent degrees of freedom were determined. The problem resolves itself into the solution of certain definite integrals, which were identified as Bessel functions of the first and second kind, and of zero and first order. The theory, based on potential flow and the Kutta condition, is fundamentally equivalent to the conventional wing section theory relating to the steady case" (p. 291).
Date: May 2, 1934
Creator: Theodorsen, Theodore
Item Type: Refine your search to only Report
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Heat transfer from finned metal cylinders in an air stream

Description: This report presents the results of tests made to supply design information for the construction of metal fins for the cooling of heated cylindrical surfaces by an air stream. A method is given for determining fin dimensions for a maximum heat transfer with the expenditure of a given amount of material for a variety of conditions of air flow and metals.
Date: April 26, 1934
Creator: Biermann, Arnold E. & Pinkel, Benjamin
Item Type: Refine your search to only Report
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Improved Apparatus for the Measurement of Fluctuations of Air Speed in Turbulent Flow

Description: This report describes recent improvements in the design of the equipment associated with the hot-wire anemometer for the measurement of fluctuating air speeds in turbulent air flow, and presents the results of some experimental investigations dealing with the response of the hot wire to speed fluctuations of various frequencies. Attempts at measuring the frequency of the fluctuations encountered in the Bureau of Standards' 54-inch wind tunnel are also reported. In addition, the difficulties enc… more
Date: 1934
Creator: Mock, W. C., Jr. & Dryden, H. L.
Item Type: Refine your search to only Report
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The influence of tip shape on the wing load distribution as determined by flight tests

Description: "Pressure measurements were made in flight on the right upper wing of an M-3 airplane. The effects of tip plan form, washout, and transverse camber were investigated with eight tip forms in unyawed conditions through the range of positive lift coefficients from zero lift to the stall. The conclusion is that the tip plan form does not influence the span distribution of the coefficients of normal force and moment. It is shown inferentially that temperature, humidity, and the aging of the wood and… more
Date: June 9, 1934
Creator: Rhode, Richard V.
Item Type: Refine your search to only Report
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The influence of wing setting on the wing load and rotor speed of a PCA-2 autogiro as determined in flight

Description: Flight tests were made on PCA-2 autogiro with wing settings of 2.2 degrees, 0.9 degrees, and -0.5 degrees. The wing load and rotor speed were measured in steady glides. The results obtained show that a wide variation in rotor speed as a function of air speed can be obtained by a suitable adjustment of the wing setting; that by decreasing the wing setting the upper safe flying speed, determined by the decrease is rotor speed, is greatly increased; and that the interference of the wing on the rot… more
Date: December 28, 1934
Creator: Wheatley, John B.
Item Type: Refine your search to only Report
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Infrared Radiation From Explosions in a Spark-Ignition Engine

Description: This report presents the results of an investigation to determine the variations in intensity and spectral distribution of the radiant energy emitted by the flames during normal and knocking explosions in an engine. Radiation extending into the infrared was transmitted by a window of fluorite, placed either near the spark plug or over the detonation zone at opposite ends of the combustion chamber. Concave, surface-silvered mirrors focused the beam, first at the slit of a stroboscope which opene… more
Date: February 27, 1934
Creator: Marvin, Charles F., Jr.; Caldwell, Frank R. & Steele, Sydney
Item Type: Refine your search to only Report
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The Measurement of the Field of View From Airplane Cockpits

Description: "A method has been devised for the angular measurement and graphic portrayal of the view obtained from the pilot's cockpit of an airplane. The assumption upon which the method is based and a description of the instrument, designated a "visiometer", used in the measurement are given. Account is taken of the fact that the pilot has two eyes and two separate sources of vision. The view is represented on charts using an equal-area polar projection, a description and proof of which are given" (p. 16… more
Date: October 3, 1934
Creator: Gough, Melvin N.
Item Type: Refine your search to only Report
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On the Theory of Laminar Boundary Layers Involving Separation

Description: "This paper presents a mathematical discussion of the laminar boundary layer, which was developed with a view of facilitating the investigation of those boundary layers in particular for which the phenomenon of separation occurs. The treatment starts with a slight modification of the form of the boundary layer equation first published by Von Mises. Two approximate solutions of this equation are found, one of which is exact at the outer edge of the boundary layer while the other is exact at the … more
Date: May 22, 1934
Creator: von Karman, T. & Millikan, C. B.
Item Type: Refine your search to only Report
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Potential Flow About Elongated Bodies of Revolution

Description: "This report presents a method of solving the problem of axial and transverse potential flows around arbitrary elongated bodies of revolution. The solutions of Laplace's equation for the velocity potentials of the axial and transverse flows, the system of coordinates being an elliptic one in a meridian plane, are given. The theory is applied to a body of revolution obtained from a symmetrical Joukowsky profile, a shape resembling an airship hull" (p. 189).
Date: November 12, 1934
Creator: Kaplan, Carl
Item Type: Refine your search to only Report
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Relative loading on biplane wings of unequal chords

Description: It is shown that the lift distribution for a biplane with unequal chords may be calculated by the method developed in NACA Technical report no. 458 if corrections are made for the inequality in chord lengths. The method is applied to four cases in which the upper chord was greater than the lower and good agreement is obtained between observed and calculated lift coefficients.
Date: May 18, 1934
Creator: Diehl, Walter S.
Item Type: Refine your search to only Report
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Scale Effect on Clark Y Airfoil Characteristics From NACA Full-Scale Wind-Tunnel Tests

Description: This report presents the results of wind tunnel tests conducted to determine the aerodynamic characteristics of the Clark Y airfoil over a large range of Reynolds numbers. Three airfoils of aspect ratio 6 and with 4, 6, and 8 foot chords were tested at velocities between 25 and 118 miles per hour, and the characteristics were obtained for Reynolds numbers (based on the airfoil chord) in the range between 1,000,000 and 9,000,000 at the low angles of attack, and between 1,000,000 and 6,000,000 at… more
Date: June 14, 1934
Creator: Silverstein, Abe
Item Type: Refine your search to only Report
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Some Factors Affecting Combustion in an Internal-Combustion Engine

Description: "An investigation of the combustion of gasoline, safety, and diesel fuels was made in the NACA combustion apparatus under conditions of temperature that permitted ignition by spark with direct fuel injection, in spite of the compression ratio of 12.7 employed. The influence of such variables as injection advance angle, jacket temperature, engine speed, and spark position was studied. The most pronounced effect was that an increase in the injection advance angle (beyond a certain minimum value) … more
Date: September 11, 1934
Creator: Rothrock, A. M. & Cohn, Mildred
Item Type: Refine your search to only Report
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Spinning characteristics of wings 1: rectangular Clark Y monoplane wing

Description: "A series of wind tunnel tests of a rectangular Clark Y wing was made with the NACA spinning balance as part of a general program of research on airplane spinning. All six components of the aerodynamic force and moment were measured throughout the range of angles of attack, angles of sideslip, and values omega b/2v likely to be attained by a spinning airplane; the results were reduced to coefficient form. It is concluded that a conventional monoplane with a rectangular Clark y wing can be made … more
Date: November 21, 1934
Creator: Bamber, M. J. & Zimmerman, C. H.
Item Type: Refine your search to only Report
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Tests of 16 related airfoils at high speed

Description: From Summary: "In order to provide information that might lead to the development of better propeller section, 13 related symmetrical airfoils were tested in the NACA high-speed wind tunnel for a study of the effect of thickness form on the aerodynamic characteristics. The thickness-form variables studies were the value of the maximum thickness, the position along the chord at which the maximum thickness occurs, and the value of the leading-edge radius. The tests were conducted through the low … more
Date: April 28, 1934
Creator: Stack, John & von Doenhoff, Albert E.
Item Type: Refine your search to only Report
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Tests of nacelle-propeller combinations in various positions with reference to wings 4: thick wing - various radial-engine cowlings - tandem propellers

Description: This report is the fourth of a series giving the results obtained from wind tunnel tests to determine the interference lift and drag and propulsive efficiency of wing-nacelle-propeller combinations. Previous reports give the results of tests with tractor propellers with various forms of nacelles and engine cowlings. This report gives the results of tests of tandem arrangements of engines and propellers in 11 positions with reference to a thick wing.
Date: January 17, 1934
Creator: McHugh, James G.
Item Type: Refine your search to only Report
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Tests of Nacelle-Propeller Combinations in Various Positions with Reference to Wings 5: Clark Y Biplane Cellule - NACA Cowled Nacelle - Tractor Propeller

Description: "This report is the fifth of a series giving the results obtained from wind tunnel tests on the interference drag and propulsive efficiency of nacelle-propeller-wing combinations. This report gives results of tests of an NACA cowled air-cooled engine nacelle with tractor propeller located in 12 positions with reference to a Clark Y biplane cellule" (p. 603).
Date: January 26, 1934
Creator: Valentine, E. Floyd
Item Type: Refine your search to only Report
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Tests of nacelle-propeller combinations in various positions with reference to wings 6: wings and nacelles with pusher propeller

Description: This report is the sixth of a series giving wind tunnel tests results on the interference drag and propulsive efficiency of nacelle-propeller-wing combinations. The present report gives the results of tests of a radial-engine nacelle with pusher propeller in 17 positions with reference to a Clark Y wing; tests of the same nacelle and propeller in three positions with reference to a thick wing; and tests of a body and pusher propeller with the thick wing, simulating the case of a propeller drive… more
Date: June 7, 1934
Creator: Wood, Donald H. & Bioletti, Carlton
Item Type: Refine your search to only Report
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Vibration response of airplane structures

Description: This report presents test results of experiments on the vibration-response characteristics of airplane structures on the ground and in flight. It also gives details regarding the construction and operation of vibration instruments developed by the National Advisory Committee for Aeronautics.
Date: May 10, 1934
Creator: Theodorsen, Theodore & Gelalles, A. G.
Item Type: Refine your search to only Report
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The Weathering of Aluminum Alloy Sheet Materials Used in Aircraft

Description: This report presents the results of an investigation of the corrosion of aluminum alloy sheet materials used in aircraft. It has for its purpose to study the causes of corrosion embrittlement in duralumin-type alloys and the development of methods for its elimination. The report contains results, obtained in an extensive series of weather-exposure tests, which reveal the extent to which the resistance of the materials to corrosion was affected by variable factors in their heat treatment and by … more
Date: March 23, 1934
Creator: Mutchler, Willard
Item Type: Refine your search to only Report
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Wind-Tunnel Research Comparing Lateral Control Devices, Particularly at High Angles of Attack 12: Upper-Surface Ailerons on Wings With Split Flaps

Description: "This report covers the twelfth of a series of tests conducted to compare different lateral control devices with particular reference to their effectiveness at high angles of attack. The present wind tunnel tests were made with two sizes of upper-surface ailerons on rectangular Clark Y wing models equipped with full span split flaps. The tests showed the effect of the upper-surface ailerons and of the split flaps on the general performance characteristics of the wings, and on the lateral contro… more
Date: June 8, 1934
Creator: Weick, Fred E. & Wenzinger, Carl J.
Item Type: Refine your search to only Report
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Wind-tunnel research comparing lateral control devices particularly at high angles of attack 13: auxiliary airfoils used as external ailerons

Description: This is the thirteenth report on a series of systematic tests comparing lateral control devices with particular reference to their effectiveness at high angles of attack. The present wind tunnel tests were made to determine the most feasible locations for lateral control surfaces mounted externally to a rectangular Clark y wing.
Date: July 23, 1934
Creator: Weick, Fred E. & Noyes, Richard W.
Item Type: Refine your search to only Report
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