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Calculation of the Lateral-Dynamic Stability of Aircraft

Description: "Graphs and formulas are given with the aid of which all the aerodynamic coefficients required for computing the lateral dynamic stability can be determined. A number of numerical examples are given for obtaining the stability derivatives and solving the characteristic-stability equation. Approximate formulas are derived with the aid of which rapid preliminary computations may be made and the stability coefficients corrected for certain modifications of the airplane" (p. 1).
Date: February 1952
Creator: Raikh, A.
Partner: UNT Libraries Government Documents Department
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Low-Speed Measurements of Rolling and Yawing Stability Derivatives of a 60 Degree Delta-Wing Model

Description: Memorandum presenting an investigation in the free-flight tunnel to determine the low-speed rolling and yawing stability derivatives of a 60 degree delta-wing model from 0 to 30 degrees angle of attack. The derivatives were measured by the free-to-damp oscillation technique and by the steady-roll technique.
Date: December 27, 1954
Creator: Johnson, Joseph L., Jr.
Partner: UNT Libraries Government Documents Department
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Some Effects of Nonlinear Variation in the Directional-Stability and Damping-in-Yawing Derivatives on the Lateral Stability of an Airplane

Description: Note presenting a theoretical investigation made to determine the effect of nonlinear stability derivatives on the lateral stability of the airplane. The results indicated that under certain conditions, a motion is obtained which has different rates of damping for the large and small amplitudes of motion, with very little damping at the small amplitudes.
Date: November 1950
Creator: Sternfield, Leonard
Partner: UNT Libraries Government Documents Department
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Generalized Analysis of Experimental Observations in Problems of Elastic Stability

Description: "A generalized method of analyzing experimental observations in problems of elastic stability is presented in which the initial readings of load and deflection may be taken at any load less the critical load. The analysis is an extension of a method published by Southwell in 1932, in which it was assumed that the initial readings are taken at zero load" (p. 1).
Date: July 1938
Creator: Lundquist, Eugene E.
Partner: UNT Libraries Government Documents Department
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Some Effects of Nonlinear Variation in the Directional-Stability and Damping-in-Yawing Derivatives on the Lateral Stability of an Airplane

Description: "A theoretical investigation has been made to determine the effect of nonlinear stability derivatives on the lateral stability of an airplane. Motions were calculated on the assumption that the directional-stability and the damping-in-yawing derivatives are functions of the angle of sideslip. The application of the Laplace transform to the calculation of an airplane motion when certain types of nonlinear derivatives are present is described in detail" (p. 1009).
Date: September 19, 1950
Creator: Sternfield, Leonard
Partner: UNT Libraries Government Documents Department
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Approximate Calculation of the Static Longitudinal Stability of Airplanes

Description: It seems desirable to have some simple method for calculating quickly and with sufficient accuracy: 1) the correct position of the center of gravity; 2) the requisite tail-group dimensions; 3) and the course of the wing and tail-group moments. In out deductions, we will first replace the biplane (disregarding the effect of stagger, decalage and induced drag) by an equivalent monoplane, whose dimensions and position in space can be approximately determined in a simple manner.
Date: November 1926
Creator: Bienen, Theodor
Partner: UNT Libraries Government Documents Department
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Investigation of Effect of Sideslip on Lateral Stability Characteristics 3: Rectangular Low Wing on Circular Fuselage With Variations in Vertical-Tail Area and Fuselage Length With and Without Horizontal Tail Surface

Description: Report presenting power-off tests made in the 6- by 6-foot test section of the stability tunnel to determine the variation of the static lateral stability characteristics with vertical-tail area, fuselage length, and wing dihedral. The results are presented as curves showing the variation of the static-lateral-stability slopes with angle of attack, and the rolling-moment, yawing-moment, and lateral-force coefficients with angle of yaw.
Date: August 1945
Creator: Hollingworth, Thomas A.
Partner: UNT Libraries Government Documents Department
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Supplemental Data and Calculations of the Lateral Stability of Airplanes

Description: In connection with the DVL Report 272 on the theory of the lateral stability of airplanes, the formal results are here amplified in some respects and their technical significance again briefly explained. Three numerical examples show how model tests for checking the lateral stability are to be evaluated and supplemented, if necessary, and how the stability limits depend on the design of the airplane and on the conditions of flight.
Date: April 1934
Creator: Mathias, Gotthold
Partner: UNT Libraries Government Documents Department
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Application of the Laplace Transformation to the Solution of the Lateral and Longitudinal Stability Equations

Description: Note presenting the application of the Laplace transformation to the solution of the lateral and longitudinal stability equations. The expressions for the time history of the motion in response to a sinusoidal control motion are derived for the general case in which all initial measurements are assumed different from zero.
Date: January 1950
Creator: Mokrzycki, G. A.
Partner: UNT Libraries Government Documents Department
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The Stability Derivatives of Low-Aspect-Ratio Triangular Wings at Subsonic and Supersonic SPeeds

Description: "Low-aspect-ratio wings having triangular plan forms are treated on the assumption that the flow potentials in planes at right angles to the long axis of the airfoils are similar to the corresponding two-dimensional potentials. Pressure distributions caused by downward acceleration, pitching, rolling, sideslipping, and yawing are obtained for wings with and without dihedral. The stability derivatives calculated from these distributions are expected to apply at both subsonic and supersonic speed… more
Date: September 1948
Creator: Ribner, Herbert S.
Partner: UNT Libraries Government Documents Department
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Damping in a roll of a missile configuration with a modified triangular wing and a cruciform tail at a Mach number of 1.52

Description: Report presenting the damping-in-roll stability derivatives of a missile configuration and its components as determined experimentally and theoretically. The experimental damping derivative of the wing-body combination was found to be 67 percent of its theoretical value. Results are given for the wing-body combination, the tail-body combination, and the wing-tail-body combination.
Date: March 6, 1951
Creator: Scherrer, Richard & Dennis, David H.
Partner: UNT Libraries Government Documents Department
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Investigation at low speeds of the effect of aspect ratio and sweep on rolling stability derivatives of untapered wings

Description: A low-scale wind-tunnel investigation was conducted in rolling flow to determine the effects of aspect ratio and sweep (when varied independently) on the rolling stability derivatives for a series of untapered wings. The rolling-flow equipment of the Langley stability tunnel was used for the tests. The data of the investigation have been used to develop a method of accounting for the effects of the drag on the yawing moment due to rolling throughout the lift range.
Date: January 19, 1949
Creator: Goodman, Alex & Fisher, Lewis R.
Partner: UNT Libraries Government Documents Department
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A Preliminary Study of the Problem of Designing High-Speed Airplanes With Satisfactory Inherent Damping of the Dutch Roll Oscillation

Description: Report presenting an investigation to create a design for fighter airplanes to have better inherent stability than most current designs. The main purpose of this design change is to obtain satisfactory stability of the Dutch roll oscillation without complicated artificial stabilizing devices. Results regarding the causes of inadequate dutch roll stability, means of improving dutch roll stability, and application of experimental design results to actual airplanes are provided.
Date: October 1953
Creator: Campbell, John P. & McKinney, Marion O., Jr.
Partner: UNT Libraries Government Documents Department
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A Survey of Methods for Determining Stability Parameters of an Airplane From Dynamic Flight Measurements

Description: Note presenting a discussion of various methods of reducing to stability parameter form the response to sinusoidal and transient disturbances, using the simplified longitudinal motion of an idealized airplane as an illustrative example. Most of this report is concerned with methods of determining transfer-function coefficients rather than stability derivatives. Examples are provided for a simplified case of longitudinal motion, but the methods presented are applicable to other, more complicated… more
Date: April 1951
Creator: Greenberg, Harry
Partner: UNT Libraries Government Documents Department
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The effects on dynamic lateral stability and control of large artificial variations in the rotary stability derivatives

Description: This report presents the results of an investigation conducted in the Langley free-flight tunnel to determine the effects of large artificial variations of several rotary lateral-stability derivatives on the dynamic lateral stability and control characteristics of a 45 degree sweptback-wing airplane model. Calculations of the period and damping of the lateral motions and of the response to roll and yaw disturbances were made for correlation with the experimental results. The calculated results … more
Date: June 20, 1952
Creator: Schade, Robert O. & Hassell, James L., Jr.
Partner: UNT Libraries Government Documents Department
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Experimental Investigation at High Subsonic Speeds of the Rolling-Stability Derivatives of a 1/22 Scale Model of the Republic F-105 Airplane

Description: Report presenting an investigation of the rolling-stability derivatives for a model of the Republic F-105 airplane over a range of Mach numbers and angles of attack. The model retained damping in roll through the test ranges, but values of the damping varied considerably with angles of attack. Derivatives of yawing moment and lateral force due to rolling generally followed previously indicated trends.
Date: June 30, 1955
Creator: Sleeman, William C., Jr. & Hayes, William C., Jr.
Partner: UNT Libraries Government Documents Department
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Correlation of Wind-Tunnel Predictions With Flight Tests of a Twin-Engine Airplane 1: Longitudinal-Stability and -Control Characteristics

Description: "The longitudinal-stability and -control characteristics of a twin-engine patrol airplane as predicted from the results of wind-tunnel tests of a powered model and as measured in flight are compared in this report. The accuracy of the wind-tunnel predictions and the reasons for discrepancies are analyzed and discussed" (p. 1).
Date: April 1945
Creator: Delany, Noel K. & Kauffman, William M.
Partner: UNT Libraries Government Documents Department
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Comparison of Linear Microinstability Calculations of Varying Input Realism

Description: The effect of varying ''input realism'' or varying completeness of the input data for linear microinstability calculations, in particular on the critical value of the ion temperature gradient for the ion temperature gradient mode, is investigated using gyrokinetic and gyrofluid approaches. The calculations show that varying input realism can have a substantial quantitative effect on the results.
Date: September 8, 2003
Creator: Rewoldt, G.
Partner: UNT Libraries Government Documents Department
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