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Airship Model Tests in the Variable Density Wind Tunnel

Description: This report presents the results of wind tunnel tests conducted to determine the aerodynamic characteristics of airship models. Eight Goodyear-Zeppelin airship models were tested in the original closed-throat tunnel. After the tunnel was rebuilt with an open throat a new model was tested, and one of the Goodyear-Zeppelin models was retested. The results indicate that much may be done to determine the drag of airships from evaluations of the pressure and skin-frictional drags on models tested at… more
Date: January 27, 1931
Creator: Abbott, Ira H.
Item Type: Refine your search to only Report
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The drag of two streamline bodies as affected by protuberances and appendages

Description: This report presents the results of wind tunnel tests of two airship models conducted to determine the drag coefficients at zero pitch, and the effect of fins and cars and of flat and streamlined protuberances located at various positions along the hull. During the investigation the stern of one model was rounded off to produce a blunter shape. The extreme range of the Reynolds number based on the over-all length of the models was from 1,300,000 to 33,000,000. At large values of the Reynolds nu… more
Date: September 26, 1932
Creator: Abbott, Ira H.
Item Type: Refine your search to only Report
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Tests in the variable-density wind tunnel of the NACA 23012 airfoil with plain and split flaps

Description: From Summary: "Section characteristics for use in wing design are presented for the NACA 23012 airfoil with plain and split flaps of 20 percent wing chord at a value of the effective Reynolds number of about 8,000,000. The flap deflections covered a range from 60 degrees upward to 75 degrees downward for the plain flap and from neutral to 90 degrees downward for the split flap. The split flap was aerodynamically superior to the plain flap in producing high maximum lift coefficients and in havin… more
Date: January 21, 1938
Creator: Abbott, Ira H. & Greenberg, Harry
Item Type: Refine your search to only Report
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Summary of Airfoil Data

Description: From Summary: "The historical development of NACA airfoils is briefly reviewed. New data are presented that permit the rapid calculation of the approximate pressure distributions for the older NACA four-digit and five-digit airfoils by the same methods used for the NACA 6-series airfoils. The general methods used to derive the basic thickness forms for NACA 6 and 7-series airfoils together with their corresponding pressure distributions are presented. Detail data necessary for the application o… more
Date: 1945
Creator: Abbott, Ira H.; von Doenhoff, Albert E. & Stivers, Louis S., Jr.
Item Type: Refine your search to only Report
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Theoretical Damping in Roll and Rolling Moment Due to Differential Wing Incidence for Slender Cruciform Wings and Wing-Body Combinations

Description: "A method of analysis based on slender-wing theory is developed to investigate the characteristics in roll of slender cruciform wings and wing-body combinations. The method makes use of the conformal mapping processes of classical hydrodynamics which transform the region outside a circle and the region outside an arbitrary arrangement of line segments intersecting at the origin. The method of analysis may be utilized to solve other slender cruciform wing-body problems involving arbitrarily assi… more
Date: 1952
Creator: Adams, Gaynor J. & Dugan, Duane W.
Item Type: Refine your search to only Report
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Investigation of Downwash, Sidewash, and Mach Number Distribution Behind a Rectangular Wing at a Mach Number of 2.41

Description: "An investigation of the nature of the flow field behind a rectangular wing of circular arc cross section has been conducted in the Langley 9-inch supersonic tunnel. Pitot- and static-pressure surveys covering a region of flow behind the wing have been made together with detailed pitot surveys throughout the region of the wake. In addition, the flow direction has been measured by means of a weathercocking vane. Theoretical calculations have been made to obtain the variation of both downwash and… more
Date: September 14, 1950
Creator: Adamson, David & Boatright, William B.
Item Type: Refine your search to only Report
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Standard nomenclature for airspeeds with tables and charts for use in calculation of airspeed

Description: Symbols and definition of various airspeed terms that have been adopted as standard by the NACA subcommittee on aircraft structural design are presented. The equations, charts, and tables required in the evaluation of true airspeed, calibrated airspeed, equivalent airspeed, impact and dynamic pressures, and Mach and Reynolds numbers have been compiled. Tables of the standard atmosphere to an altitude of 65,000 feet and a tentative extension to an altitude of 100,000 feet are given along with th… more
Date: July 17, 1946
Creator: Aiken, William S., Jr.
Item Type: Refine your search to only Report
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The Pack Method for Compressive Tests of Thin Specimens of Materials Used in Thin-Wall Structures

Description: "The strength of modern lightweight thin-wall structures is generally limited by the strength of the compression members. An adequate design of these members requires a knowledge of the compressive stress-strain graph of the thin-wall material. The "pack" method was developed at the National Bureau of Standards with the support of the National Advisory Committee for Aeronautics to make possible a determination of compressive stress-strain graphs for such material" (p. 133).
Date: August 23, 1938
Creator: Aitchison, C. S. & Tuckerman, L. B.
Item Type: Refine your search to only Report
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Theoretical and Experimental Investigation of the Subsonic-Flow Fields Beneath Swept and Unswept Wings with Tables or Vortex-Induced Velocities

Description: "The flow-field characteristics beneath swept and unswept wings as determined by potential-flow theory are compared with the experimentally determined flow fields beneath swept and unswept wing-fuselage combinations. The potential-flow theory utilized considered both spanwise and chordwise distributions of vorticity as well as the wing-thickness effects. The perturbation velocities induced by a unit horseshoe vortex are included in tabular form" (p. 1).
Date: 1957
Creator: Alford, William J., Jr.
Item Type: Refine your search to only Report
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Determination of vortex paths by series expansion technique with application to cruciform wings

Description: A series method of determining two-dimensional vortex paths is considered and applied to the computation of vortex positions behind a slender equal-span cruciform wing at any angle of bank as a function of the distance behind the trailing edge. Calculated paths are shown for four bank angles. For a bank angle of 45 degrees comparison is made with the results of a closed expression given in NACA-TN-2605. For other bank angles water-tank experiments provide qualitative comparison. Satisfactory ag… more
Date: February 8, 1956
Creator: Alksne, Alberta Y.
Item Type: Refine your search to only Report
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Calculation of the chordwise load distribution over airfoil sections with plain, split, or serially hinged trailing-edge flaps

Description: From Summary: "A method is presented for the rapid calculation of the incremental chordwise normal-force distribution over an airfoil section due to the deflection of a plain flap or tab, a split flap, or a serially hinged flap. This report is intended as a supplement to NACA Report no. 631, wherein a method is presented for the calculation of the chordwise normal-force distribution over an airfoil without a flap or, as it may be considered, an airfoil with flap (or flaps) neutral. The method e… more
Date: 1938
Creator: Allen, H. Julian
Item Type: Refine your search to only Report
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General theory of airfoil sections having arbitrary shape or pressure distribution

Description: In this report a theory of thin airfoils of small camber is developed which permits either the velocity distribution corresponding to a given airfoil shape, or the airfoil shape corresponding to a given velocity distribution to be calculated. The procedures to be employed in these calculations are outlined and illustrated with suitable examples.
Date: 1945
Creator: Allen, H. Julian
Item Type: Refine your search to only Report
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A study of the motion and aerodynamic heating of ballistic missiles entering the earth's atmosphere at high supersonic speeds

Description: From Summary: "A simplified analysis of the velocity and deceleration history of ballistic missiles entering the earth's atmosphere at high supersonic speeds is presented. The results of this motion analysis are employed to indicate means available to the designer for minimizing aerodynamic heating. The heating problem considered involves not only the total heat transferred to a missile by convection, but also the maximum average and local time rates of convective heat transfer."
Date: April 28, 1953
Creator: Allen, H. Julian & Eggers, A. J., Jr.
Item Type: Refine your search to only Report
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A method for calculating heat transfer in the laminar flow region of bodies

Description: This report has been prepared to provide a practical method for determining the chordwise distribution of the rate of heat transfer from the surface of a wing or body of revolution to air. The method is limited in use to the determination of heat transfer from the forward section of such bodies when the flow is laminar. A comparison of the calculated average heat-transfer coefficient for the nose section of the wing of a Lockheed 12-A airplane with that experimentally determined shows a satisfa… more
Date: 1943
Creator: Allen, H. Julian & Look, Bonne C.
Item Type: Refine your search to only Report
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A study of effects of viscosity on flow over slender inclined bodies of revolution

Description: From Summary: "The observed flow field about slender inclined bodies of revolution is compared with the calculated characteristics based upon potential theory. The comparison is instructive in indicating the manner in which the effects of viscosity are manifest. Based on this and other studies, a method is developed to allow for viscous effects on the force and moment characteristics of bodies. The calculated force and moment characteristics of two bodies of high fineness ratio are shown to be … more
Date: 1951
Creator: Allen, H. Julian & Perkins, Edward W.
Item Type: Refine your search to only Report
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Wall interference in a two-dimensional-flow wind tunnel, with consideration of the effect of compressibility

Description: From Summary: "Theoretical tunnel-wall corrections are derived for an airfoil of finite thickness and camber in a two-dimensional-flow wind tunnel. The theory takes account of the effects of the wake of the airfoil and of the compressibility of the fluid, and is based upon the assumption that the chord of the airfoil is small in comparison with the height of the tunnel. Consideration is given to the phenomenon of choking at high speeds and its relation to the tunnel-wall corrections. The theore… more
Date: 1944
Creator: Allen, H. Julian & Vincenti, Walter G.
Item Type: Refine your search to only Report
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Glues Used in Airplane Parts

Description: This report was prepared for the National Advisory Committee for Aeronautics and presents the results of investigations conducted by the Forest Products Laboratory of the United States Forest Service on the manufacture, preparation, application, testing and physical properties of the different types of glues used in wood airplane parts.
Date: 1920
Creator: Allen, S. W. & Truax, T. R.
Item Type: Refine your search to only Report
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Method for studying helicopter longitudinal maneuver stability

Description: A theoretical analysis of helicopter maneuver stability is made and the results are compared with experimental results for both a single and a tandem rotor helicopter. Techniques are described for measuring in flight the significant stability derivatives for use with the theory to aid in design studies of means for achieving marginal maneuver stability for a prototype helicopter.
Date: October 1953
Creator: Amer, Kenneth B.
Item Type: Refine your search to only Report
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Charts for estimating tail-rotor contribution to helicopter directional stability and control in low-speed flight

Description: "Theoretically derived charts and equations are presented by which tail-rotor design studies of directional trim and control response at low forward speed can be conveniently made. The charts can also be used to obtain the main-rotor stability derivatives of thrust with respect to collective pitch and angle of attack at low forward speeds. The use of the charts and equations for tail-rotor design studies is illustrated. Comparisons between theoretical and experimental results are presented. The… more
Date: October 27, 1953
Creator: Amer, Kenneth B. & Gessow, Alfred
Item Type: Refine your search to only Report
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Studies of the lateral-directional flying qualities of a tandem helicopter in forward flight

Description: An investigation of the lateral-directional flying qualities of a tandem-rotor helicopter in forward flight was undertaken to determine desirable goals for helicopter lateral-directional flying qualities and possible methods of achieving these goals in the tandem-rotor helicopter. Comparison between directional stability as measured in flight and rotor-off model tests in a wind tunnel shows qualitative agreement and, hence, indicates such wind-tunnel test, despite the absence of the rotors, to … more
Date: 1954
Creator: Amer, Kenneth B. & Tapscott, Robert J.
Item Type: Refine your search to only Report
open access

Equations, Tables, and Charts for Compressible Flow

Description: "This report, which is a revision and extension of NACA-TN-1428, presents a compilation of equations, tables, and charts useful in the analysis of high-speed flow of a compressible fluid. The equations provide relations for continuous one-dimensional flow, normal and oblique shock waves, and Prandtl-Meyer expansions for both perfect and imperfect gases. The tables present useful dimensionless ratios for continuous one-dimensional flow and for normal shock waves as functions of Mach number for a… more
Date: 1953
Creator: Ames Research Staff
Item Type: Refine your search to only Report
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A Résumé of the Advances in Theoretical Aeronautics Made by Max M. Munk

Description: "In order to apply profitably the mathematical methods of hydrodynamics to aeronautical problems, it is necessary to make simplifications in the physical conditions of the latter. In a valuable paper presented by Dr. Max M. Munk, of the National Advisory Committee for Aeronautics, Washington, to the Delft Conference in April, 1924, these necessary simplifying assumptions are discussed in detail. It is the purpose of the present paper to present in as simple a manner as possible some of the inte… more
Date: 1926
Creator: Ames, Joseph S.
Item Type: Refine your search to only Report
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Determination of control-surface characteristics from NACA plain-flap and tab data

Description: From Summary: "The data from previous NACA pressure-distribution investigations of plain flaps and tabs with sealed gaps have been analyzed and are presented in this paper in a form readily applicable to the problems of control-surface design. The experimentally determined variation of aerodynamic parameters with flap chord and tab chord are given in chart form and comparisons are made with the theory. With the aid of these charts and the theoretical relationships for a thin airfoil, the aerody… more
Date: 1941
Creator: Ames, Milton B., Jr. & Sears, Richard I.
Item Type: Refine your search to only Report
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