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Full-scale tests of metal propellers at high tip speeds

Description: This report describes tests of 10 full-scale metal propellers of several thickness ratios at various tip speeds up to 1,350 feet per second. The results indicate no loss of efficiency up to tip speeds of approximately 1,000 feet per second. Above this tip speed the loss is at a rate of about 10 per cent per 100 feet per second increase relative to the efficiency at the lower speeds for propellers of pitch diameter ratios 0.3 to 0.4. Propellers having sections of small thickness ratio can be run… more
Date: November 5, 1930
Creator: Wood, Donald H.
Partner: UNT Libraries Government Documents Department
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Tests of nacelle-propeller combinations in various positions with reference to wings. Part I : thick wing-N.A.C.A. cowled nacelle-tractor propeller

Description: This report gives the results in the 20-foot propeller research tunnel of the National Advisory Committee for Aeronautics on the interference drag and propulsive efficiency of a nacelle-propeller combination located in 21 positions with reference to a thick wing. The lift, drag, and propulsive efficiency were obtained at several angles of attack for each of the 21 locations. A net efficiency was derived for determining the over-all effectiveness of each nacelle location. Best results were obtai… more
Date: November 18, 1931
Creator: Wood, Donald H.
Partner: UNT Libraries Government Documents Department
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The effect on airplane performance of the factors that must be considered in applying low-drag cowling to radial engines

Description: From Summary: "This report presents the results of flight tests with three different airplanes using several types of low-drag cowling for radial air-cooled engines. The greater part of the tests were made with a Curtiss XF7Cc-1 (Sea Hawk) with a 410 horsepower. Wasp engine, using three fuselage nose shapes and six types of outer cowling. The six cowlings were: a narrow ring, a wide ring, a wide cowling similar in the original NACA cowling, a thick ring incorporating an exhaust collector, a sin… more
Date: November 25, 1931
Creator: McAvoy, William H.; Schey, Oscar W. & Young, Alfred W.
Partner: UNT Libraries Government Documents Department
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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.
Partner: UNT Libraries Government Documents Department
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The NACA variable-density wind tunnel

Description: This report describes the redesigned variable-density wind tunnel of the National Advisory Committee for Aeronautics; it supersedes a previous report that described the original tunnel. The operation of the balance and the method of testing are explained and the method of correcting and presenting airfoil data is described. A summary of the formulas for predicting the characteristics of finite wings from the airfoil section data as they are usually presented is also given.
Date: November 23, 1933
Creator: Jacobs, Eastman N. & Abbott, Ira H.
Partner: UNT Libraries Government Documents Department
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Flight Investigation of Lateral Control Devices for Use With Full-Span Flaps

Description: This report presents the results of flight tests made on five different lateral control devices that appeared adaptable to wings fitted with full span flaps: controllable auxiliary airfoils (airfoils mounted above and forward of the leading edge of the wings), external ailerons (airfoils mounted above the wing and slightly forward of its maximum ordinate), upper-surface ailerons (similar to split trailing-edge flaps except that they constitute the upper surface of the wing), ailerons that retra… more
Date: November 7, 1934
Creator: Soulé, H. A. & McAvoy, W. H.
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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The drag of airplane wheels, wheel fairings, and landing gears - 3

Description: The tests reported in this report conclude the investigation of landing-gear drag that has been carried out in the NACA 20-foot wind tunnel. They supplement earlier tests (reported in Technical Report No. 485) made with full-scale dummy wheels, wheel fairings, and landing gears intended for airplanes of 3,000 pounds gross weight and include tests of tail wheels and tail skids.
Date: November 21, 1934
Creator: Herrnstein, William H., Jr. & Biermann, David
Partner: UNT Libraries Government Documents Department
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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.
Partner: UNT Libraries Government Documents Department
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Air flow around finned cylinders

Description: Report presents the results of a study made to determine the air-flow characteristics around finned cylinders. Air-flow distribution is given for a smooth cylinder, for a finned cylinder having several fin spacings and fin widths, and for a cylinder with several types of baffle with various entrance and exit shapes. The results of these tests show: that flow characteristics around a cylinder are not so critical to changes in fin width as they are to fin spacing; that the entrance of the baffle … more
Date: November 7, 1935
Creator: Brevoort, M. J. & Rollin, Vern G.
Partner: UNT Libraries Government Documents Department
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Tests of a Wing-Nacelle-Propeller Combination at Several Pitch Settings Up to 42 Degrees

Description: This report presents the results of tests of a 4-foot model of Navy propeller No. 4412 in conjunction with an NACA cowled nacelle mounted ahead of a thick wing in the 20-foot propeller-research tunnel. A range of propeller pitches from 17 degrees to 42 degrees at 0.75r was covered, and for this propeller the efficiency reached a maximum at a pitch setting of 27 degrees; at high pitches the efficiencies were slightly lower. The corrected propulsive efficiency is shown to be independent of the an… more
Date: November 12, 1935
Creator: Windler, Ray
Partner: UNT Libraries Government Documents Department
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Blower Cooling of Finned Cylinders

Description: "Several electrically heated finned steel cylinders enclosed in jackets were cooled by air from a blower. The effect of the air conditions and fin dimensions on the average surface heat-transfer coefficient q and the power required to force the air around the cylinders were determined. Tests were conducted at air velocities between the fins from 10 to 130 miles per hour and at specific weights of the air varying from 0.046 to 0.074 pound per cubic foot. The fin dimensions of the cylinders cover… more
Date: November 14, 1936
Creator: Schey, Oscar W. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department
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An Analysis of Lateral Stability in Power-Off Flight With Charts for Use in Design

Description: "The aerodynamic and mass factors governing lateral stability are discussed and formulas are given for their estimation. Relatively simple relationships between the governing factors and the resulting stability characteristics are presented. A series of charts is included with which approximate stability characteristics may be rapidly estimated" (p. 1).
Date: November 17, 1936
Creator: Zimmerman, Charles H.
Partner: UNT Libraries Government Documents Department
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Span load distribution for tapered wings with partial-span flaps

Description: Tables are given for determining the load distribution of tapered wings with partial-span flaps placed either at the center or at the wing tips. Seventy-two wing-flap combinations, including two aspect ratios, four taper ratios, and nine flap lengths, are included. The distributions for the flapped wing are divided into two parts, one a zero lift distribution due primarily to the flaps and the other an additional lift distribution due to an angle of attack of the wing as a whole. Comparison bet… more
Date: November 21, 1936
Creator: Pearson, H. A.
Partner: UNT Libraries Government Documents Department
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Fuel spray and flame formation in a compression-ignition engine employing air flow

Description: "The effects of air flow on fuel spray and flame formation in a high-speed compression-ignition engine have been investigated by means of the NACA combustion apparatus. The process was studied by examining high-speed motion pictures taken at the rate of 2,200 frames a second. The combustion chamber was of the flat-disk type used in previous experiments with this apparatus. The air flow was produced by a rectangular displacer mounted on top of the engine piston. Three fuel-injection nozzles were… more
Date: November 25, 1936
Creator: Rothrock, A. M. & Waldron, C. D.
Partner: UNT Libraries Government Documents Department
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A discussion of certain problems connected with the design of hulls of flying boats and the use of general test data

Description: Report presents the results of a survey of problems encountered in applying general test data to the design of flying-boat hulls. It is shown how basic design features may be readily determined from special plots of test data. A study of the effect of the size of a flying boat on the probable limits to be covered by the general test data is included and recommendations for special tests and new methods of presenting test data for direct use in design are given.
Date: November 1937
Creator: Diehl, Walter S.
Partner: UNT Libraries Government Documents Department
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The experimental and calculated characteristics of 22 tapered wings

Description: From Summary: "The experimental and calculated aerodynamic characteristics of 22 tapered wings are compared, using tests made in the variable-density wind tunnel. The wings had aspect ratios from 6 to 12 and taper ratios from 1:6:1 and 5:1. The compared characteristics are the pitching moment, the aerodynamic-center position, the lift-curve slope, the maximum lift coefficient, and the curves of drag. The method of obtaining the calculated values is based on the use of wing theory and experiment… more
Date: November 17, 1937
Creator: Anderson, Raymond F.
Partner: UNT Libraries Government Documents Department
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Compressible Flow About Symmetrical Joukowski Profiles

Description: "The method of Poggi is employed for the determination of the effects of compressibility upon the flow past an obstacle. A general expression for the velocity increment due to compressibility is obtained. The general result holds whatever the shape of the obstacle; but, in order to obtain the complete solution, it is necessary to know a certain Fourier expansion of the square of the velocity of flow past the obstacle. An application is made to the case flow of a symmetrical Joukowski profile wi… more
Date: November 19, 1937
Creator: Kaplan, Carl
Partner: UNT Libraries Government Documents Department
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Pressure Distribution Over Airfoils With Fowler Flaps

Description: Report presents the results of tests made of a Clark y airfoil with a Clark y Fowler flap and of an NACA 23012 airfoil with NACA Fowler flaps. Some of the tests were made in the 7 by 10-foot wind tunnel and others in the 5-foot vertical wind tunnel. The pressures were measured on the upper and lower surfaces at one chord section both on the main airfoils and on the flaps for several angles of attack with the flaps located at the maximum-lift settings.
Date: November 24, 1937
Creator: Wenzinger, Carl J. & Anderson, Walter B.
Partner: UNT Libraries Government Documents Department
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Interference of Tail Surfaces and Wing and Fuselage from Tests of 17 Combinations in the N.A.C.A. Variable-Density Tunnel

Description: "An investigation of the interference associated with tail surfaces added to wing-fuselage combinations was included in the interference program in progress in the NACA variable-density tunnel. The results indicate that, in aerodynamically clean combinations, the increment of the high-speed drag can be estimated from section characteristics within useful limits of accuracy. The interference appears mainly as effects on the downwash angle and as losses in the tail effectiveness and varies with t… more
Date: November 5, 1938
Creator: Sherman, Albert
Partner: UNT Libraries Government Documents Department
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Tensile Elastic Properties of 18:8 Chromium-Nickel Steel as Affected by Plastic Deformation

Description: "The relationship between stress and strain, and between stress and permanent set, for 18:8 alloy as affected by prior plastic deformation is discussed. Hysteresis and creep and their effects on the stress-strain and stress-set curves are also considered, as well as the influence of duration of the rest interval after cold work and the influence of plastic deformation on proof stresses, on the modulus of elasticity at zero stress, and on the curvature of the stress-strain line. A constant (c su… more
Date: November 22, 1938
Creator: McAdam, D. J., Jr. & Mebs, R. W.
Partner: UNT Libraries Government Documents Department
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Mechanical Properties of Flush-Riveted Joints

Description: "The strength of representative types of flush-riveted joints has been determined by testing 865 single-shearing, double-shearing, and tensile specimens representing 7 types of rivet and 18 types of joint. The results, presented in graphic form, show the stress at failure, type of failure, and d/t ratio. In general, dimpled joints were appreciably stronger than countersunk or protruding-head joints, but their strength was greatly influenced by constructional details" (p. 467).
Date: November 1939
Creator: Brueggeman, W. C. & Roop, Frederick C.
Partner: UNT Libraries Government Documents Department
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Effect of fuel-air ratio, inlet temperature, and exhaust pressure on detonation

Description: From Summary: "An accurate determination of the end-gas condition was attempted by applying a refined method of analysis to experimental results. The results are compared with those obtained in Technical Report no. 655. The experimental technique employed afforded excellent control over the engine variables and unusual cyclic reproducibility. This, in conjunction with the new analysis, made possible the determination of the state of the end-gas at any instant to a fair degree of precision. Resu… more
Date: November 15, 1939
Creator: Taylor, E. S.; Leary, W. A. & Diver, J. R.
Partner: UNT Libraries Government Documents Department
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