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Cloud-droplet ingestion in engine inlets with inlet velocity ratios of 1.0 and 0.7

Description: From Summary: "The paths of cloud droplets into two engine inlets have been calculated for a wide range of meteorological and flight conditions. The amount of water in droplet form ingested by the inlets and the amount and distribution of water impinging on the inlet walls are obtained from these droplet-trajectory calculations. In both types of inlet, a prolate ellipsoid of revolution represents either part or all of the forebody at the center of an annular inlet to an engine. The configuratio… more
Date: November 2, 1955
Creator: Brun, Rinaldo J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A theoretical study of the aerodynamics of slender cruciform-wing arrangements and their wakes

Description: A theoretical study is made of the pressures, loadings, forces, and vortex wake associated with certain cruciform wing arrangements. For 45 degree bank, the wake of a cruciform wing is treated numerically with 40 vortices and analytically with 4 vortices. Comparisons are made with water-tank measurements, and the calculation of loads on cruciform tails by reverse flow considered.
Date: October 25, 1955
Creator: Spreiter, John R. & Sacks, Alvin H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Linearized Lifting-Surface and Lifting-Line Evaluations of Sidewash Behind Rolling Triangular Wings at Supersonic Speeds

Description: "The lifting-surface sidewash behind rolling triangular wings has been derived for a range of supersonic Mach numbers for which the wing leading edges remain swept behind the mark cone emanating from the wing apex. Variations of the sidewash with longitudinal distance in the vertical plane of symmetry are presented in graphical form. An approximate expression for the sidewash has been developed by means of an approach using a horseshoe-vortex approximate-lifting-line theory" (p. 455).
Date: October 21, 1955
Creator: Bobbitt, Percy J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theoretical span load distributions and rolling moments for sideslipping wings of arbitrary plan form in incompressible flow

Description: From Summary: "A method of computing span loads and the resulting rolling moments for sideslipping wings of arbitrary plan form in incompressible flow is derived. The method requires that the span load at zero sideslip be known for the wing under consideration. Because this information is available for a variety of wings, this requirement should not seriously restrict the application of the present method. The basic method derived herein requires a mechanical differentiation and integration to … more
Date: October 6, 1955
Creator: Queijo, M. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A method for simulating the atmospheric entry of long-range ballistic missiles

Description: From Summary: "It is demonstrated with the aid of similitude arguments that a model launched from a hypervelocity gun upstream through a special supersonic nozzle should experience aerodynamic heating and resulting thermal stresses like those encountered by a long-range ballistic missile entering the earth's atmosphere. This demonstration hinges on the requirements that model and missile be geometrically similar and made of the same material, and that they have the same flight speed and Reynold… more
Date: September 15, 1955
Creator: Eggers, A. J., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of the compressive strength and creep lifetime of 2024-T3 aluminum-alloy plates at elevated temperatures

Description: The results of elevated-temperature compressive strength and creep tests of 2024-t3 (formerly 24s-t3) aluminum alloy plates supported in v-grooves are presented. The strength-test results indicate that a relation previously developed for predicting plate compressive strength for plates of all materials at room temperature is also satisfactory for determining elevated-temperature strength. Creep-lifetime results are presented for plates in the form of master creep-lifetime curves by using a time… more
Date: September 8, 1955
Creator: Mathauser, Eldon E. & Deveikis, William D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An experimental study of applied ground loads in landing

Description: Results are presented of an experimental investigation made of the applied ground loads and the coefficient of friction between the tire and the ground during the wheel spin-up process in impacts of a small landing gear under controlled conditions on a concrete landing strip in the Langley impact basin. The basic investigation included three major phases: impacts with forward speed at horizontal velocities up to approximately 86 feet per second, impacts with forward speed and reverse wheel rota… more
Date: August 18, 1955
Creator: Milwitzky, Benjamin; Lindquist, Dean C. & Potter, Dexter M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Lift Hysteresis at Stall as an Unsteady Boundary-Layer Phenomenon

Description: "Analysis of rotating stall of compressor blade rows requires specification of a dynamic lift curve for the airfoil section at or near stall, presumably including the effect of lift hysteresis. Consideration of the Magnus lift of a rotating cylinder suggests performing an unsteady boundary-layer calculation to find the movement of the separation points of an airfoil fixed in a stream of variable incidence. The consideration of the shedding of vorticity into the wake should yield an estimate of … more
Date: August 17, 1955
Creator: Moore, Franklin K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nonlifting Wing-Body Combinations With Certain Geometric Restraints Having Minimum Wave Drag at Low Supersonic Speeds

Description: "Several variational problems involving optimum wing and body combinations having minimum wave drag for different kinds of geometrical restraints are analyzed. Particular attention is paid to the effect on the wave drag of shortening the fuselage and, for slender axially symmetric bodies, the effect of fixing the fuselage diameter at several points or even of fixing whole portions of its shape" (p. 113).
Date: August 4, 1955
Creator: Lomax, Harvard
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Error in airspeed measurement due to the static-pressure field ahead of an airplane at transonic speeds

Description: The magnitude and variation of the static-pressure error for various distances ahead of sharp-nose bodies and open-nose air inlets and for a distance of 1 chord ahead of the wing tip of a swept wing are defined by a combination of experiment and theory. The mechanism of the error is discussed in some detail to show the contributing factors that make up the error. The information presented provides a useful means for choosing a proper location for measurement of static pressure for most purposes. more
Date: August 3, 1955
Creator: O'Bryan, Thomas C.; Danforth, Edward C. B. & Johnston, J. Ford
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Summary of derived gust velocities obtained from measurements within thunderstorms

Description: Available measurements of the derived gust velocities within thunderstorms are summarized for altitudes from 5,000 to 34,000 feet. The results indicate that the intensity of the derived gust velocity is essentially constant up to altitudes of 20,000 feet and that an approximate 10-percent reduction in the gust intensity occurs for altitudes from 20,000 to 30,000 feet.
Date: July 27, 1955
Creator: Tolefson, H. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Influence of Alloying upon Grain-Boundary Creep

Description: "Grain-boundary displacement, occurring in bicrystals during creep at elevated temperature (350 degrees c), has been measured as a function of the copper content (0.1 to 3 percent) in a series of aluminum-rich aluminum-copper solid-solution alloys. The minimums in stress and temperature, below which grain-boundary motion does not occur, increase regularly with the copper content as would be expected if recovery is necessary for movement. Otherwise, the effects, if any, of the copper solute upon… more
Date: June 24, 1955
Creator: Rhines, F. N.; Bond, W. E. & Kissel, M. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

NACA Transonic Wind-Tunnel Test Sections

Description: Report presents an approximate subsonic theory for the solid-blockage interference in circular wind tunnels with walls slotted in the direction of flow. This theory indicated the possibility of obtaining zero blockage interference. Tests in a circular slotted tunnel based on the theory confirmed the theoretical predictions.
Date: June 20, 1955
Creator: Wright, Ray H. & Ward, Vernon G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

On boattail bodies of revolution having minimum wave drag

Description: The problem of determining the shape of slender boattail bodies of revolution for minimum wave drag has been reexamined. It was found that minimum solutions for Ward's slender-body drag equation can exist only for the restricted class of bodies for which the rate of change of cross-sectional area at the base is zero. In order to eliminate this restriction, certain higher order terms must be retained in the drag equation and isoperimetric relations. The minimum problem for the isoperimetric cond… more
Date: June 8, 1955
Creator: Harder, Keith C. & Rennemann, Conrad, Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Incompressible Flutter Characteristics of Representative Aircraft Wings

Description: "This report gives the results of a detailed study of the flutter characteristics of four representative aircraft wings. This study was made using the electric-analog computer at the California Institute of Technology. During the course of this investigation eight important parameters of each wing were varied and, in addition, the effects of mass, inertia, pitching spring, and location of a concentrated mass were investigated for all four wings and at several sweepback angles" (p. 1385).
Date: June 6, 1955
Creator: Wilts, C. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigation of some wake vortex characteristics of an inclined ogive-cylinder body at Mach number 2

Description: For a body consisting of a fineness-ratio-3 ogival nose tangent to a cylindrical afterbody 7.3 diameters long, pitot-pressure distributions in the flow field, pressure distributions over the body, and downwash distributions along a line through the vortex centers have been measured for angles of attack to 20 degrees. The Reynolds numbers, based on body diameter, were 0.15 x 10 to the 6th power and 0.44 x 10 to the 6th power. Comparisons of computed and measured vortex paths and downwash distrib… more
Date: May 31, 1955
Creator: Jorgensen, Leland H. & Perkins, Edward W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Influence of Hot-Working Conditions on High-Temperature Properties of a Heat-Resistant Alloy

Description: "The relationships between conditions of hot-working and properties at high temperatures and the influence of the hot-working on response to heat treatment were investigated for an alloy containing nominally 20 percent molybdenum, 2 percent tungsten, and 1 percent columbium. Commercially produced bar stock was solution-treated at 2,200 degrees F. to minimize prior-history effects and then rolled at temperatures of 2,200 degrees, 2,100 degrees, 2,000 degrees, 1,800 degrees, and 1,600 degrees F. … more
Date: May 20, 1955
Creator: Ewing, John F. & Freeman, J. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Extrapolation techniques applied to matrix methods in neutron diffusion problems

Description: "A general matrix method is developed for the solution of characteristic-value problems of the type arising in many physical applications. The scheme employed is essentially that of Gauss and Seidel with appropriate modifications needed to make it applicable to characteristic-value problems. An iterative procedure produces a sequence of estimates to the answer; and extrapolation techniques, based upon previous behavior of iterants, are utilized in speeding convergence. Theoretically sound limit… more
Date: May 12, 1955
Creator: McCready, Robert R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effect of Interaction on Landing-Gear Behavior and Dynamic Loads in a Flexible Airplane Structure

Description: "The effects of interaction between a landing gear and a flexible airplane structure on the behavior of the landing gear and the loads in the structure have been studied by treating the equations of motion of the airplane and the landing gear as a coupled system. The landing gear is considered to have nonlinear characteristics typical of conventional gears, namely, velocity-squared damping, polytropic air-compression springing, and exponential tire force-deflection characteristics. For the case… more
Date: May 5, 1955
Creator: Cook, Francis E. & Milwitzky, Benjamin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis and Calculation by Integral Methods of Laminar Compressible Boundary-Layer With Heat Transfer and With and Without Pressure Gradient

Description: From Introduction: "The purpose of the present report is to present a comprehensive summary of theoretical investigations of comprehensible laminar boundary layers which have been carried out since 1949 at the Polytechnic Institute of Brooklyn under the sponsorship and with the financial assistance of the National Advisory Committee for Aeronautics. The results of these investigations are contained primarily in references 1 to 7."
Date: April 12, 1955
Creator: Morduchow, Morris
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An analysis of once-per-revolution oscillating aerodynamic thrust loads on single-rotation propellers on tractor airplanes at zero yaw

Description: A simplified procedure is shown for calculating the once-per-revolution oscillating aerodynamic thrust loads on propellers of tractor airplanes at zero yaw. The only flow field information required for the application of the procedure is a knowledge of the upflow angles at the horizontal center line of the propeller disk. Methods are presented whereby these angles may be computed without recourse to experimental survey of the flow field. The loads computed by the simplified procedure are compar… more
Date: March 21, 1955
Creator: Rogallo, Vernon L.; Yaggy, Paul F. & McCloud, John L., III
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Theoretical analysis of incompressible flow through a radial-inlet centrifugal impeller at various weight flows

Description: A method for the solution of the incompressible nonviscous flow through a centrifugal impeller, including the inlet region, is presented. Several numerical solutions are obtained for four weight flows through an impeller at one operating speed. These solutions are refined in the leading-edge region. The results are presented in a series of figures showing streamlines and relative velocity contours. A comparison is made with the results obtained by using a rapid approximate method of analysis.
Date: March 4, 1955
Creator: Kramer, James J.; Prian, Vasily D. & Wu, Chung-Hua
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Contributions on the Mechanics of Boundary-Layer Transition

Description: "The manner in which flow in a boundary layer becomes turbulent was investigated on a flat plate at wind speeds generally below 100 feet per second. Hot-wire techniques were used, and many of the results are derived from oscillograms of velocity fluctuations in the transition region. Following a presentation of the more familiar aspects of transition, there are presented the very revealing facts discovered while studying the characteristics of artificially produced turbulent spots" (p. 853).
Date: February 28, 1955
Creator: Schubauer, G. B. & Klebanoff, P. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

On the Kernel function of the integral equation relating lift and downwash distributions of oscillating wings in supersonic flow

Description: From Summary: "This report treats the Kernel function of the integral equation that relates a known or prescribed downwash distribution to an unknown lift distribution for harmonically oscillating wings in supersonic flow. The treatment is essentially an extension to supersonic flow of the treatment given in NACA report 1234 for subsonic flow. For the supersonic case the Kernel function is derived by use of a suitable form of acoustic doublet potential which employs a cutoff or Heaviside unit f… more
Date: February 15, 1955
Creator: Watkins, Charles E. & Berman, Julian H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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