National Advisory Committee for Aeronautics (NACA) - 46 Matching Results

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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
Partner: UNT Libraries Government Documents Department
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Cooling characteristics of a 2-row radial engine

Description: This report presents the results of cooling tests conducted on a calibrated GR-1535 Pratt and Whitney Wasp, Jr. Engine installed in a Vought X04U-2 airplane. The tests were made in the NACA full-scale tunnel at air speeds from 70 to 120 miles per hour, at engine speeds from 1,500 to 2,600 r.p.m., and at manifold pressures from 19 to 33 inches of mercury absolute. A Smith controllable propeller was used to facilitate obtaining the different combinations of engine speed, power, and manifold press… more
Date: December 4, 1934
Creator: Schey, Oscar W. & Rollin, Vern G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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A Flight Investigation of the Lateral Control Characteristics of Short Wide Ailerons and Various Spoilers With Different Amounts of Wing Dihedral

Description: This report presents the results of flight tests made to determine the lateral control characteristics of short wide ailerons and spoilers, as a consequence of the promise shown in wind-tunnel tests by these devices as means of obtaining lateral control, particularly at angles of attack above the stall. Several forms of spoilers, front-hinge, rear-hinge, plain retractable, and saw-tooth retractable were tested alone and in combination with the ailerons. The tests were made with several differen… more
Date: May 19, 1934
Creator: Weick, Fred E.; Soulé, Hartley A. & Gough, Melvin N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A description and test results of a spark-ignition and a compression-ignition 2-stroke-cycle engine

Description: This report presents performance results of air cooled and water-cooled engines. The results obtained were sufficiently promising to warrant further investigation with fuel injection and spark ignition, with the same arrangement of inlet ports and exhaust valves at the bottom of the cylinder and the exhaust gases discharged through two poppet valves in the cylinder head. The displacement of the engine was 118 cubic inches. Optimum performance was obtained with the inlet air directed into the cy… more
Date: May 14, 1934
Creator: Spanogle, J. A. & Whitney, E. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Computation of the two-dimensional flow in a laminar boundary layer

Description: A comparison is made of the boundary-layer flow computed by the approximate method developed by K. Pohlhausen with the exact solutions which have been published for several special cases. A modification of Pohlhausen's method has been developed which extends the range of application at the expense of some decrease in the accuracy of the approximations.
Date: May 1934
Creator: Dryden, Hugh L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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The Effect of Spray Strips on the Take-Off Performance of a Model of a Flying-Boat Hull

Description: "The effect on the take-off performance of a model of the hull of a typical flying boat, Navy PH-1, of fitting spray strips of four different widths, each at three different angles, was determined by model tests in the NACA Tank. Spray strips of widths up to 3 percent of the beam improve the general performance at speeds near the hump and reduce the spray thrown. A downward angle of 30 degrees to 45 degrees in the neighborhood of the step seems most favorable for the reduction of the spray" (p.… more
Date: June 15, 1934
Creator: Truscott, Starr
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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Analysis of 2-Spar Cantilever Wings With Special Reference to Torsion and Load Transference

Description: "This paper deals with the analysis of 2-spar cantilever wings in torsion, taking cognizance of the fact that the spars are not independent, but are interconnected by ribs and other structural members. The principles of interaction are briefly explained, showing that the mutual relief action occurring depends on the "pure torsional stiffness" of the wing cross section. Various practical methods of analysis are outlined" (p. 45).
Date: April 10, 1934
Creator: Kuhn, Paul
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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General equations for the stress analysis of rings

Description: In this report it is shown that the shear, axial force, and moment at one point in a simple ring subjected to any loading condition can be given by three independent equations involving certain integrals that must be evaluated regardless of the method of analysis used. It is also shown how symmetry of the ring alone or of the ring and the loading about 1 or 2 axes makes it possible to simplify the three equations and greatly reduces the number of integrals that must be evaluated. Application of… more
Date: August 10, 1934
Creator: Lundquist, Eugene E. & Burke, Walter F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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The effect of baffles on the temperature distribution and heat-transfer coefficients of finned cylinders

Description: This report presents the results of an investigation to determine the effect of baffles on the temperature distribution and the heat-transfer coefficient of finned cylinders. The tests were conducted in a 30-inch wind tunnel on electrically heated cylinders with fins of 0.25 and 0.31 inch pitch. The results of these tests showed that the use of integral baffles gave a reduction of 31.9 percent in the rear wall temperatures and an increase of 54.2 percent in the heat transfer coefficient as comp… more
Date: September 26, 1934
Creator: Schey, Oscar W. & Rollin, Vern G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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Experimental investigation of the Robinson-type cup anemometer

Description: This report presents the results of wind tunnel tests on a Robinson-type anemometer. The investigation covered force measurements on individual cups, as well as static and dynamic torque measurements and calibrations on complete cup wheels. In the tests on individual cups 5 cup forms were used and in the measurements on complete cup wheels 4 cup wheels with 3 arm lengths for each cup wheel were tested. All the results are presented in graphical form.
Date: October 10, 1934
Creator: Brevoort, M. J. & Joyner, U. T.
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 PCA-2 autogiro rotor

Description: This report presents the results of force tests on and air-flow surveys near PCA-2 autogiro rotor in the NACA full-scale wind tunnel. The force tests were made at three pitch settings and several rotor speeds; the effect of fairing protuberances on the rotor blade was determined. Induced downwash and yaw angles were determined at low tip-speed ratios in a plane 1 1/2 feet above the path of the blade tips. The results show that the maximum l/d of the rotor cannot be appreciably increased by incr… more
Date: October 12, 1934
Creator: Wheatley, John B. & Hood, Manley J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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