National Advisory Committee for Aeronautics (NACA) - 4,107 Matching Results

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Boundary-Induced Upwash for Yawed and Swept-Back Wings in Closed Circular Wind Tunnels

Description: Report presenting a determination of the tunnel-induced velocities for yawed and swept-back airfoils in a closed circular wind tunnel. Calculations were performed for elemental horseshoe vortices with one tip of the bound vortex on the tunnel axis for a range of yaw angles and bound-vortex lengths.
Date: May 1947
Creator: Eisenstadt, Bertram J.
Partner: UNT Libraries Government Documents Department
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Matrix Methods for Calculating Cantilever-Beam Deflections

Description: Note presenting the method of numerical integration for calculation of beam deflection in matrix form to give it the advantages which are inherent in an influence-coefficient method. Examples are presented to show that the use of weighted matrices reduces the calculation time required to obtain a desired degree of accuracy.
Date: March 1949
Creator: Benscoter, Stanley U. & Gossard, Myron L.
Partner: UNT Libraries Government Documents Department
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Data on Optimum Length, Shear Strength, and Tensile Strength of Age-Hardened 17S-T Machine-Countersunk Rivets in 75S-T Sheet

Description: Report presenting a series of tensile-strength and shear-strength tests made on age-hardened 17S-T rivets machine-countersunk in 75S-T sheets. The results of the tests indicated that the joints can be made satisfactorily with regard to both flushness and strength if the ratio of buck to diameter is kept to a certain value.
Date: March 1947
Creator: Schuette, Evan H. & Niles, Donald E.
Partner: UNT Libraries Government Documents Department
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Flight Measurements of Helicopter Blade Motion With a Comparison Between Theoretical and Experimental Results

Description: Note presenting photographic records of the behavior of a blade in flight as obtained with a conventional single-rotor helicopter. The results of the measurements of flapping motion, in-plane motion, and blade distortions are presented for selected conditions of flight at tip-speed ratios ranging from 0.12 to 0.25. Plots of blade twisting and blade bending in the plane of flapping are presented for a sample case.
Date: April 1947
Creator: Myers, Garry C., Jr.
Partner: UNT Libraries Government Documents Department
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The streamline pattern in the vicinity of an oblique airfoil

Description: "A method for determining the streamwise flow pattern of a nonviscous incompressible fluid about an oblique airfoil from the corresponding flow pattern about the airfoil in normal position is presented and illustrated in two examples. The method can be extended to account approximately for compressibility effects by applying the Prandtl-Glauert correction factor to the flow pattern that is normal to the leading edge of the airfoil. The method is expected to be useful in determining the shape of… more
Date: March 1947
Creator: Watkins, Charles E.
Partner: UNT Libraries Government Documents Department
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Effect of forebody warp on the hydrodynamic qualities of a hypothetical flying boat having a hull length-beam ratio of 15

Description: Report of an investigation of the effect of forebody warp on the hydrodynamic qualities of a hypothetical flying boat with a hull length-beam ratio of 15 in smooth water and in waves. Warping the forebody planing bottom was found to appreciably increase the range of stable trim between the lower and upper trim limits of stability, although the center-of-gravity limits of stability were reduced.
Date: March 1949
Creator: Carter, Arthur W. & Weinstein, Irving
Partner: UNT Libraries Government Documents Department
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Flight Tests of a Helicopter in Autorotation, Including a Comparison With Theory

Description: Note presenting the results of glide performance tests conducted on a test helicopter with its original production blades in the autorotation condition. The data was reduced to coefficient form, and performance at standard sea-level conditions were calculated.
Date: April 1947
Creator: Gessow, Alfred & Myers, Garry C., Jr.
Partner: UNT Libraries Government Documents Department
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Data on the Compressive Strength of 75S-T6 Aluminum-Alloy Flat Panels with Longitudinal Extruded Z-Section Stiffeners

Description: "The experimental results are presented for a part of an investigation of the compressive strength of 75S-T6 aluminum-alloy flat panels with longitudinal extruded Z-section stiffeners. This part of the investigation is concerned with panels in which the ratio of the thickness of the stiffener material to the skin material varies from 0.4 to 1.0 and the ratio of stiffener spacing to skin thickness varies from 15 to 40" (p. 1).
Date: March 1949
Creator: Hickman, William A. & Dow, Norris F.
Partner: UNT Libraries Government Documents Department
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Experimental and calculated characteristics of several NACA 44-series wings with aspect ratios of 8, 10, and 12 and taper ratios of 2.5 and 3.5

Description: The aerodynamic characteristics of seven unswept tapered wings were determined by calculation from two-dimensional data and by wind-tunnel tests in order to demonstrate the accuracy of the calculations and to show some of the effects of aspect ratio, taper ratio, and root thickness-chord ratio. The characteristics were calculated by the usual application of the lifting-line theory which assumes linear section lift curves and also by an application of the theory which allows the use of nonlinear… more
Date: May 1947
Creator: Neely, Robert H.; Bollech, Thomas V.; Westrick, Gertrude C. & Graham, Robert R.
Partner: UNT Libraries Government Documents Department
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Investigation of Effects of Surface Temperature and Single Roughness Elements on Boundary-Layer Transition

Description: Note presenting an investigation of the laminar boundary layer and the position of the transition point on a heated flat plate. The Reynolds number of transition was found to decrease as the temperature of the plate is increased. Results regarding the effect of surface temperature, effect of roughness elements, mean-velocity profile near a heated wall, instability of inflection-point profiles, and laminar separation and transition are provided.
Date: April 1947
Creator: Liepmann, Hans W. & Fila, Gertrude H.
Partner: UNT Libraries Government Documents Department
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A Discussion of the Application of the Prandtl-Glauert Method to Subsonic Compressible Flow Over a Slender Body of Revolution

Description: Note presenting an analysis of the use of the Prandtl-Glauert method for subsonic potential flow of a compressible fluid. This paper specifically focuses on the difference between the two- and three-dimensional flow when using this method.
Date: September 1946
Creator: Lees, Lester
Partner: UNT Libraries Government Documents Department
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A preliminary study of a propeller powered by gas jets issuing from the blade tips

Description: From Summary: "Computations are made of the performance of a propeller designed to develop 56 thrust horsepower at 100 miles per hour. The fuel consumption of the jet-operated propeller would be considerably higher than that of a reciprocating engine and a propeller. The lighter weight of the jet-operated propeller will result in a lighter weight of engine plus fuel for short-range flights. A theoretical analysis is made of a propeller powered by gas jets issuing from the blade tips."
Date: November 1946
Creator: Sanders, J. C. & Sanders, N. D.
Partner: UNT Libraries Government Documents Department
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Comparison of relative sensitivities of the knock limits of two fuels to six engine variables

Description: Report presenting knock testing of a sensitive fuel and a relatively insensitive fuel in a full-scale air-cooled cylinder. Six engine variables were investigated: fuel-air ratio, compression ratio, inlet-air temperature, spark advance, exhaust pressure, and cylinder temperature.
Date: August 1946
Creator: Cook, Harvey A.; Held, Louis F. & Pritchard, Ernest I.
Partner: UNT Libraries Government Documents Department
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Flow Tests of an NACA-Designed Supercharger Inlet Elbow and the Effects of Various Components on the Flow Characteristics at the Elbow Outlet

Description: Note presenting an investigation on a supercharger inlet elbow designed to have a uniform velocity distribution at the outlet with a minimum pressure loss through the bend. The effects of a vane, an impeller-shaft housing, and the combination of the two on the outlet-velocity distribution and total pressure drop through the elbow were determined.
Date: October 1946
Creator: Guentert, D. C.; Todd, D. J. & Simmons, W. P., Jr.
Partner: UNT Libraries Government Documents Department
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Column and Plate Compressive Strengths of Aircraft Structural Materials: Extruded 0-1HTA Magnesium Alloy

Description: Column and plate compressive strengths of extruded 0-1HTA magnesium alloy were determined both within and beyond the elastic range from tests of flat end H-section columns and from local instability tests of H-, Z-, and channel section columns. These tests are part of an extensive research investigation to provide data on the structural strength of various aircraft materials. The results are presented in the form of curves and charts that are suitable for use in the design and analysis of aircr… more
Date: January 1947
Creator: Heimerl, George J. & Niles, Donald E.
Partner: UNT Libraries Government Documents Department
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Corrosion tests of a heated wing utilizing an exhaust-gas-air mixture for ice prevention

Description: Report presenting an investigation of the exhaust of corrosive attack in an aluminum alloy wing employing an exhaust-gas-air mixture as a heating medium for ice prevention. There were no cases of structurally serious corrosion on either painted or plain specimens removed from the wing for detailed microscopic and metallurgic examination.
Date: January 1949
Creator: Holdaway, George H.
Partner: UNT Libraries Government Documents Department
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Methods for Determination and Computation of Flow Patterns of a Compressible Fluid

Description: Note presenting a well-known method of generating stream functions of an incompressible fluid flow, which involves taking the imaginary part of an analytic function of a complex variable. This paper is specifically devoted to a detailed discussion of performing computations related to obtaining flow patterns of compressible fluid from analytic functions of a compressible fluid. An example is also provided to illustrate the method.
Date: September 1946
Creator: Bergman, Stefan
Partner: UNT Libraries Government Documents Department
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An investigation of the aerodynamic characteristics of a rotating axial-flow blade grid

Description: Report presenting the results of an experimental investigation of the aerodynamic characteristics of a rotating axial-flow blade grid with pressure-increasing effect. Several techniques of measurement were used, including pressure distribution measurements, pitot tubes, and hot wire wake surveys. Results regarding the lift and pressure drag of the blade sections, aerodynamic characteristics of the blade sections, profile drag, and static pressure are provided.
Date: February 1947
Creator: Weske, John R.
Partner: UNT Libraries Government Documents Department
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Study by the Prandtl-Glauert method of compressibility effects and critical Mach number for ellipsoids of various aspect ratios and thickness ratios

Description: From Summary: "By the use of a form of the Prandtl-Glauert method that is valid for three-dimensional flow problems, the value of the maximum incremental velocity for compressible flow about thin ellipsoids at zero angle of attack is calculated as a function of the Mach number for various aspect ratios and thickness ratios. The critical Mach numbers (within the accuracy of the Prandtl-Glauert method) of the various ellipsoids are also determined. The results indicate an increase in critical Mac… more
Date: January 1949
Creator: Hess, Robert V. & Gardner, Clifford S.
Partner: UNT Libraries Government Documents Department
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Performance of Hoods for Aircraft Exhaust-Gas Turbines

Description: Report presenting the performance of a turbosupercharger turbine with three types of exhaust hood. The results for conical hoods, flat-nozzle hoods, and short-turning-radius hoods are provided.
Date: November 1946
Creator: Turner, L. Richard; Lowdermilk, Warren H. & Lord, Albert M.
Partner: UNT Libraries Government Documents Department
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Compressive Strength of 24S-T Aluminum-Alloy Flat Panels With Longitudinal Formed Hat-Section Stiffeners

Description: "Results are presented for a part of a test program on 24S-T aluminum alloy flat compression panels with longitudinal formed hat-section stiffeners. This part of the program is concerned with panels in which the thickness of the stiffener materials is 0.625 times the skin thickness. The results, presented in tabular and graphical form, show the effect of the relative dimensions of the panel on the buckling stress and the average stress at maximum load" (p. 1).
Date: December 1946
Creator: Schuette, Evan H.; Barab, Saul & McCracken, Howard L.
Partner: UNT Libraries Government Documents Department
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Investigation of Meteorological Conditions Associated with Aircraft Icing in Layer-Type Clouds for 1947-48 Winter

Description: Rotating-cylinder measurements of the icing conditions encountered in flight during the winter of 1947-48 are presented. Liquid water content, drop size, and temperature data are shown to be consistent with previously measured conditions and with proposed maximum icing conditions in supercooled layer-type clouds. Cumulative frequency graphs of meteorological parameters indicate the frequency with which various icing conditions have been encountered in the Great Lakes area and surrounding states. more
Date: January 1949
Creator: Kline, Dwight B.
Partner: UNT Libraries Government Documents Department
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Gust-tunnel investigation of a wing model with semichord line swept back 30 degrees

Description: Report presenting tests in the gust tunnel of the 30 degree sweptback wing model to provide information on some of the problems encountered in the prediction of gust loads for airplanes incorporating swept wings. The results indicate that within the scope of the data and the values of gradient distance investigated, the maximum acceleration increment depends on the slope of the lift curve of an equivalent straight wing multiplied by the cosine of the angle of sweep and on the effect of gradual … more
Date: January 1949
Creator: Reisert, Thomas D.
Partner: UNT Libraries Government Documents Department
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The Synthesis and Purification of Aromatic Hydrocarbons 1: Butylbenzene

Description: "A 13-gallon quantity of butylbenzene was synthesized and purified by large-scale preparation of 4-phenyl-1-butene from benzyl-magnesium chloride and allyl chloride with subsequent hydrogenation of the olefin. The physical constants for pure samples of 4-phenyl-1-butene and butylbenzene were determined and the position of the double bond in the olefin was established" (p. 1).
Date: January 1946
Creator: Karabinos, Joseph V. & Lamberti, Joseph M.
Partner: UNT Libraries Government Documents Department
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