Technical Report Archive & Image Library (TRAIL) - 1,263 Matching Results

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A Theoretical Investigation of the Lateral Oscillations of an Airplane With Free Rudder With Special Reference to the Effect of Friction

Description: Report presenting charts showing the variation in dynamic stability with the rudder hinge-moment characteristics. A stabilizing rudder floating tendency combined with a high degree of aerodynamic balance is shown to lead to oscillations of increasing amplitude.
Date: March 1943
Creator: Greenberg, Harry & Sternfield, Leonard
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Theoretical Investigation of the Rolling Oscillations of an Airplane With Ailerons Free

Description: Report discusses an analysis of the stability of an airplane with ailerons free, with particular attention to the motions when the ailerons have a tendency to float against the wind. Information about the aerodynamic balance of the plane and oscillations that may be encountered are included. The effects of friction in the control system is also explored.
Date: January 1944
Creator: Cohen, Doris
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory and Application of Hot-Wire Instruments in the Investigation of Turbulent Boundary Layers

Description: Report presenting an account of the recent developments in hot-wire instruments for use in turbulent boundary layers to determine the magnitude of the several components of the turbulent velocity fluctuations together with the correlation between them and turbulent shearing stress.
Date: March 1946
Creator: Schubauer, G. B. & Klebanoff, P. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory and preliminary flight tests of an all-movable vertical tail surface

Description: Report presenting flight testing of an improved type of all-movable tail surface. The particular arrangement tested provides control-free stability and a stable variation of the control forces during maneuvers. Results regarding rudder effectiveness, directional stability, rudder-free lateral motion, and rudder-free turns are provided.
Date: January 1943
Creator: Jones, Robert T. & Kleckner, Harold F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory of Mechanical Oscillations of Rotors With Two Hinged Blades

Description: Report discusses an investigation into the mechanical stability of a rotor with two vertically hinged blades mounted on symmetrical supports of equal stiffness and mass. Information about the instability regions and effect of damping is included. The two-blade rotor was found to have two shaft-critical speeds at which instability can occur as well as a second region at which self-excited vibrations occur.
Date: September 1943
Creator: Feingold, Arnold M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Theory of Propellers 1: Determination of the Circulation Function and the Mass Coefficient for Dual-Rotating Propellers

Description: Report presenting values of the circulation function for dual-rotating propellers. Numerical values are given for four-, eight-, and twelve-blade dual-rotating propellers and for advance ratios from 2 to about 6.
Date: August 1944
Creator: Theodorsen, Theodore
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Theory of Propellers 2: Method for Calculating the Axial Interference Velocity

Description: "A technical method is given for calculating the axial interference velocity of a propeller. The method involves the use of certain weight functions P, Q, and F. Numerical values for the weight functions are given for two-blade, three-blade, and six-blade propellers" (p. 53).
Date: September 19, 1944
Creator: Theodorsen, Theodore
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Theory of Propellers 3: The Slipstream Contraction With Numerical Values for Two-Blade and Four-Blade Propeller

Description: Report presenting the magnitude of slipstream contraction, which provides information about the conditions of the ultimate wake. Curves and tables are given for the contraction coefficient of two-blade and four-blade propellers for various values of the advance ratio; the contraction coefficient is defined as the contraction in the diameter of the wake helix in terms of the wake diameter at infinity.
Date: November 1944
Creator: Theodorsen, Theodore
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Theory of Propellers 4: Thrust, Energy, and Efficiency Formulas for Single- and Dual-Rotating Propellers With Ideal Circulation Distribution

Description: Report presenting simple and exact expressions for the efficiency of single- and dual-rotating propellers with ideal circulation distribution as given by Goldstein functions for single-rotating propellers and by the new functions for dual-rotating propellers from part I of this series. Efficiency is found to depend primarily on a defined load factor and on an axial loss factor. Tables and graphs are included for practical use of the results.
Date: November 1944
Creator: Theodorsen, Theodore
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory of Self-Excited Mechanical Oscillations of Hinged Rotor Blades

Description: "Vibrations of rotary-wing aircraft may derive their energy from the rotation of the rotor rather than from the air forces. A theoretical analysis of these vibrations is described and methods for its application are explained herein" (p. 1). Information about self-excited speed range and shaft-critical speed are provided for any rotor with more than two blades.
Date: July 1943
Creator: Coleman, Robert P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermodynamic Data for the Computation of the Performance of Exhaust-Gas Turbines

Description: "Information published in chemical journals from 1933 to 1939 on the thermodynamic properties of the component gases of exhaust gases based on spectroscopic measurements were used as data for computing the ideal values of work, mass flow, nozzle velocity, power, and temperature change involved in the thermodynamic properties of a gas turbine. Curves from which this information can conveniently be obtained are given. An additional curve is included from which the heat flow may be calculated for … more
Date: October 1945
Creator: Pinkel, Benjamin & Turner, L. Richard
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tire friction coefficients and their relation to ground-run distance in landing

Description: Report presenting a summary of published information on braking friction coefficients. Analysis indicates that the magnitude of the friction coefficient available will affect the technique required for obtaining the shortest ground run only under extreme conditions.
Date: June 1942
Creator: Gustafson, F. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Torsion Tests of Stiffened Circular Cylinders

Description: "The design of curved sheet panels to resist shear involves a consideration of several factors: the buckling resistance of the sheet, the stress at which buckling becomes permanent, and the strength which may be developed beyond the buckling limit by tension-field action. Although some experimental as well as theoretical work has been done on the buckling and tension-field phases of this problem, neither of these types of action appears to be very well understood. This report presents the resul… more
Date: May 1944
Creator: Moore, R. L. & Wescoat, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Trends in Surface-Ignition Temperatures

Description: Report discusses the variation of surface-ignition temperature with charge density, fuel-air ratio, and surface-ignition advance. Tests on several fuels were conducted on a supercharged CFR engine to determine surface-ignition temperature as a function of the three variables. It was concluded that surface-ignition temperature is not a satisfactory criterion for differentiating between preignition characteristics of different fuels.
Date: September 1944
Creator: Alquist, Henry E. & Male, Donald W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Tunnel-Wall Corrections to Rolling and Yawing Moments Due to Aileron Deflection in Closed Rectangular Wind Tunnels

Description: "A method is developed for calculating the tunnel-wall corrections to rolling and yawing moments due to aileron deflection on models in closed rectangular wing tunnels. Graphs are presented which permit a rapid determination of these corrections for models mounted in 7- by 10-foot or 8- by 12-foot wind tunnels. The method is so developed that the corrections may be calculated for the deflection of either aileron alone or both ailerons simultaneously" (p. 1).
Date: January 1945
Creator: Graham, Donald J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Two-Dimensional Incompressible Potential Flow Over Corrugated and Distorted Infinite Surfaces

Description: "The two-dimensional incompressible potential flow over corrugations and bumps of arbitrary shape is derived by conformal transformation. The results are compared with those obtained by the methods of thin-airfoil theory. Some discussion is included of the flow over bumps that protrude both inward and outward from a wall" (p. 1).
Date: January 1945
Creator: Perl, W. & Green, L. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Two-dimensional wind-tunnel investigation of 0.20-airfoil-chord plain ailerons of different contour on an NACA 65(sub 1)-210 airfoil section

Description: Report presenting an investigation of three interchangeable sealed-gap 0.20-airfoil-chord plain ailerons of different contour on the NACA 65(sub 1)-210 airfoil section. The three aileron contours tested were the true airfoil contour, straight sides, and a beveled trailing edge. Results regarding the aileron effectiveness, aileron hinge moments, lift, pitching moment, and drag are provided.
Date: December 1945
Creator: Underwood, William J.; Braslow, Albert L. & Cahill, Jones F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Two-Dimensional Wind-Tunnel Investigation of Six Airfoil Sections for the Wing of the Vega XP2V-1 Airplane

Description: Report discussing testing of six airfoil sections for the wing of the Vega XP2V-1 airplane in a smooth condition and with standard leading-edge roughness. Information about the lift, drag, pitching-moment characteristics, and sensitivity to roughness is provided. No airfoil was found to be superior to the others in all categories.
Date: October 1945
Creator: Fullmer, Felicien F., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Two-Dimensional Wind-Tunnel Investigation of Spoiler Aileron Flap Model for the Hughes XF-11 Airplane

Description: Report discussing testing on a retractable spoiler aileron on the NACA 66(215)-216 airfoil with a 25-percent-chord slotted flap. The effects of spoiler thickness, spoiler gap, spoiler bevel angle, spoiler roughness, and flap deflection on aerodynamic characteristics are described.
Date: April 1945
Creator: Underwood, William J. & Fullmer, Felicien F., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Two-Dimensional Wind-Tunnel Investigation of Two NACA Low-Drag Airfoil Sections Equipped With Slotted Flaps and a Plain NACA Low-Drag Airfoil Section for XF6U-L Airplane

Description: Report discussing the results of testing to determine the aerodynamic characteristics of three NACA-designed airfoil sections, some with flaps equipped. The tests included determination of the aerodynamic characteristics of the airfoils in smooth conditions and with standard roughness applied to the leading edge. Lift tests were also carried out at a range of flap deflections.
Date: January 1946
Creator: Loftin, Lawrence K., Jr. & Rice, Fred J., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Ultraviolet Absorption Spectra of Aromatic Amines in Isooctane and in Water

Description: Report discusses the results of a study of the ultraviolet absorption spectra in the 3200 A to 2500 A region of 27 aromatic amines in iscoctane and and in water solutions. Factors that affect the absorption spectra of aromatic amines were investigated, and the spectra in the two different solvents were compared. The main variables affecting the absorption are the nature of the solvent, the purity of the aromatic amines, and photochemical decomposition of the aromatic amines.
Date: November 1945
Creator: Tischler, Adelbert O. & Howard, J. Nelson
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Ultraviolet spectrochemical analysis for aromatics in aircraft fuels

Description: Report presenting tests to verify and extend ultraviolet spectroscopic techniques for applications to the analysis of aviation fuels for their aromatic constituents. Results regarding photographic absorption spectra, spectrophotometric absorption spectra, and spectrophotometric analyses are provided.
Date: March 1945
Creator: Cleaves, Alden P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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