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Determination of the Profile Drag of an Airplane Wing in Flight at High Reynolds Numbers

Description: Report presenting flight tests to determine the profile-drag coefficients of a portion of the original wing surface of an all-metal airplane and a portion of the wing made aerodynamically smooth and more nearly fair than the original section. Tests were also carried out to determine the point of transition from laminar to turbulent boundary layer and to determine the velocity distribution along the upper surface of the wing.
Date: 1939
Creator: Bicknell, Joseph
Item Type: Refine your search to only Report
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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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Hydrodynamic and Aerodynamic Tests of a Family of Models of Seaplane Floats With Varying Angles of Dead Rise: N.A.C.A. Models 57-A, 57-B, and 57-C

Description: Report presenting testing of three models of V-bottom floats for twin-float seaplanes with varying angles of dead rise were tested in a tank and a wind tunnel. Results regarding the effect of angle of dead rise, height and amount of spray at hump speed, aerodynamic drag, effect of cross-sectional shape and load coefficients, and spray strips are provided.
Date: July 1939
Creator: Parkinson, John B.; Olson, Roland E. & House, Rufus O.
Item Type: Refine your search to only Report
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General Potential Theory of Arbitrary Wing Sections

Description: The problem of determining the two dimensional potential flow around wing sections of any shape is examined. The problem is condensed into the compact form of an integral equation capable of yielding numerical solutions by a direct process. An attempt is made to analyze and coordinate the results of earlier studies relating to properties of wing sections. The existing approximate theory of thin wing sections and the Joukowski theory with its numerous generalizations are reduced to special cases… more
Date: November 4, 1932
Creator: Theodorsen, T. & Garrick, I. E.
Item Type: Refine your search to only Report
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An Application of the Von Kármán-Millikan Laminar Boundary-Layer Theory and Comparison With Experiment

Description: Note presenting the von Kármán-Millikan theory of laminar boundary layers as applied to the laminar boundary layer about an elliptical cylinder on which boundary-layer and pressure-distribution measurements. Good agreement is obtained between calculated and experimental results, meaning that the method may be generally applied to the laminar boundary layer about any body provided that an experimentally determined pressure distribution is available.
Date: October 1935
Creator: von Doenhoff, Albert E.
Item Type: Refine your search to only Report
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An Approximate Spin Design Criterion for Monoplanes

Description: "An approximate empirical criterion, based on the projected side area and the mass distribution of the airplane, was formulated. The British results were analyzed and applied to American designs. A simpler design criterion, based solely on the type and the dimensions of the tail, was developed; it is useful in a rapid estimation of whether a new design is likely to comply with the minimum requirements for safety in spinning" (p. 1).
Date: June 1936
Creator: Seidman, Oscar & Donlan, Charles J.
Item Type: Refine your search to only Report
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Method of Testing Oxygen Regulators

Description: Oxygen regulators are used in aircraft to regulate automatically the flow of oxygen to the pilot from a cylinder at pressures ranging up to 150 atmospheres. The instruments are adjusted to open at an altitude of about 15,000 ft. and thereafter to deliver oxygen at a rate which increases with the altitude. The instruments are tested to determine the rate of flow of oxygen delivered at various altitudes and to detect any mechanical defects which may exist.
Date: June 1935
Creator: Sontag, Harcourt & Borlik, E. L.
Item Type: Refine your search to only Report
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Tank Tests of a Model of the NC Flying-Boat Hull - N.A.C.A. Model 44

Description: "A 1/7.06 full-size model of the NC-type hull was tested in the N.A.C.A. tank by both the general method and the specific or free-to-trim method. The results of the tests are given in curves plotted as non dimensional coefficients and are compared with the test results of N.A.C.A. model 11-A. The NC model (N.A.C.A. model 44) shows higher resistance than model 11-A at hump speed but lower resistance at high speeds. Model 44 has a higher best trim angle at the jump and a lower maximum positive tr… more
Date: May 1936
Creator: Bell, Joe W.
Item Type: Refine your search to only Report
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Landing characteristics of an autogiro

Description: An investigation to determine the rate of descent, the horizontal velocity, and the attitude at contact of an autogiro in landings was made by the National Advisory Committee for Aeronautics at the request of the Bureau of Air Commerce, Department of Commerce. The investigation covered various types of landings. The results of the investigation disclosed that the maximum rate of descent at contact with the ground (10.6 feet per second) was less than the minimum rate of descent attainable in a s… more
Date: November 1934
Creator: Peck, William C.
Item Type: Refine your search to only Report
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Tank Tests of Two Floats for High-Speed Seaplanes

Description: "At the request of the Bureau of Aeronautics, Navy Department, a study of the design of floats especially suitable for use on high-speed seaplanes was undertaken in the N.A.C.A. tank. This note give the results obtained in tests of one-quarter full-size models of two floats for high-speed seaplanes. One was a float similar to that used on the Macchi high-speed seaplane which competed in the 1926 Schneider Trophy races, and the other a float designed at the N.A.C.A. tank in an attempt to improve… more
Date: November 1933
Creator: Bell, Joe W.
Item Type: Refine your search to only Report
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Tank Tests of Flat and V-Bottom Planning Surfaces

Description: "Four planing surfaces, all having beams of 16 inches and lengths of 60 inches but varying in dead rise by 10 degrees increments from 0 degrees to 30 degrees, were tested in the N.A.C.A. tank. The results cover a wide range of speed, loads, and trim angles, and are applicable to a variety of problems encountered in the design of seaplanes. The data are analyzed to determine the characteristics of each surface at the trim angle giving minimum resistance for all the speed and loads tested. A plan… more
Date: November 1934
Creator: Shoemaker, James M.
Item Type: Refine your search to only Report
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The Effect of Depth of Step on the Water Performance of a Flying-Boat Hull Model N.A.C.A. Model 11-C

Description: "NACA model 11-C was tested with four different depths of step to obtain information as to the effect of the depth of step on the water performance. The depths of step were selected to cover the practicable range of depths and in each case the included angle between the forebody and afterbody keels was kept the same 6-1/2 degrees. Small depths of step were found to give lower resistance at speeds below and at the hump speed of the model and greater depths of step lower resistance at high speeds… more
Date: July 1935
Creator: Bell, Joe W.
Item Type: Refine your search to only Report
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Comparison of Three Methods for Calculating the Compressive Strength of Flat and Slightly Curved Sheet and Stiffener Combinations

Description: "This report gives a comparison of the accuracy of the three methods for calculating the compressive strength of flat sheet and stiffener combinations such as occur in stressed-skin or monocoque structures for aircraft. Of the three methods based upon various assumptions with regard to the interaction of sheet and stiffener, the method based upon mutual action of the stiffener and an effective width as a column gave the best agreement with the results of the tests. An investigation of the effec… more
Date: March 1933
Creator: Lundquist, Eugene E.
Item Type: Refine your search to only Report
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Effect of stabilizer location upon pitching and yawing moments in spins as shown by tests with the spinning balance

Description: Tests were made with the spinning balance in a 5-foot wind tunnel to study the effect of stabilizer location upon the pitching and yawing moments given by the tail surfaces in spinning attitudes. The tests revealed that the horizontal surfaces, when in a normal location, seriously reduced the effectiveness of the fin and rudder, particularly at angles of attack of 50 degrees or more. The tests also revealed that a more forward or more rearward location gave no consistent or decided improvement;… more
Date: November 1933
Creator: Bamber, M. J. & Zimmerman, C. H.
Item Type: Refine your search to only Report
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A preliminary determination of normal accelerations on racing airplanes

Description: "Rules and methods for insuring safe structural strength of racing airplanes used in the major air meets in this country have recently been considered. Acceleration records made in racing airplanes during actual air races were therefore considered desirable, and the NACA undertook the measurement of acceleration of loads on airplanes during all conditions of flight. Accelerations were measured on four airplanes at the Miami All-American Races in January 1934 and January 1935" (p. 1).
Date: August 1935
Creator: Scudder, N. F. & Kirschbaum, H. W.
Item Type: Refine your search to only Report
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The Calculated Effect of Trailing-Edge Flaps on the Take-Off of Flying Boats

Description: "The results of take-off calculations are given for an application of simple trailing-edge flaps to two hypothetical flying boats, one having medium wing and power loading and consequently considerable excess of thrust over total resistance during the take-off run, the other having high wing and power loading and a very low excess thrust. For these seaplanes the effect of downward flap settings was: (1) to increase the total resistance below the stalling speed, (2) to decrease the get-away spee… more
Date: November 1934
Creator: Parkinson, J. B. & Bell, J. W.
Item Type: Refine your search to only Report
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A general tank test of NACA model 11-C flying-boat hull, including the effect of changing the plan form of the step

Description: The results of a general tank test model 11-C, a conventional pointed afterbody type of flying-boat hull, are given in tables and curves. These results are compared with the results of tests on model 11-A, from which model 11-C was derived, and it is found that the resistance of model 11-C is somewhat greater. The effect of changing the plan form of the step on model 11-C is shown from the results of tests made with three swallow-tail and three pointed steps formed by altering the original step… more
Date: August 1935
Creator: Dawson, John R.
Item Type: Refine your search to only Report
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Tests of N.A.C.A. airfoils in the variable-density wind tunnel. Series 230

Description: The results of tests of six airfoils having the N.A.C.A. 230 mean line and varying in thickness from 0.06c to 0.21c are presented. These results agree with previous findings in showing that aerodynamically the best section is one of moderate thickness. The data are of value mainly in connection with the design of tapered wings having sections based on the N.A.C.A. 230 mean line.
Date: May 1936
Creator: Jacobs, Eastman N. & Pinkerton, Robert M.
Item Type: Refine your search to only Report
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A study of the pitching moments and the stability characteristics of monoplanes

Description: "This note presents a study of the pitching moments and the stability characteristics of monoplanes. Expressions for the pitching-moment coefficient and the Diehl stability coefficient for the monoplane are developed, suitable for the use of airplane designers. The effective difference between the high-wing and low-wing types is portrayed and discussed. Comparisons between experimental and computed values are made. Charts for use in the solution of numerical values of the pitching-moment and st… more
Date: November 1934
Creator: Higgins, George J.
Item Type: Refine your search to only Report
open access

The Aerodynamic Effect of a Retractable Landing Gear

Description: "Tests were conducted in the N.A.C.A. full scale wind tunnel at the request of the Army Air Corps to determine the effect of retractable landing gear openings in the bottom surface of a wing upon the characteristics of a Lockheed Altair airplane. The tests were extended to include the determination of the lift and drag characteristics throughout the angle-of-attack range with the landing gear both retracted and extended. Covering the wheel openings in the wing with sheet metal when the wheels w… more
Date: March 1933
Creator: DeFrance, Smith J.
Item Type: Refine your search to only Report
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