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Showing 1 to 18 of 18 for “"stability derivatives"”.
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Analysis of various forced oscillation techniques for obtaining dynamic stability derivatives
… wind tunnel methods for obtaining dynamic stability derivatives for aircrafts at high angle of attack are described. From the general equations of motion of an aircraft in space, the perturbation equations of motion are derived for applying to a wind tunnel aircraft model. Data Reduction …
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Analysis of the dynamic stability derivatives for high angle of attack aircraft
Modern, high performance aircraft are required to be able to fly and be controlled over a wide variety of flight conditions. In order to predict the aircraft behavior and control requirements over the entire flight regime it is necessary to have a proper aerodynamic model. Flight conditions at high …
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Investigating Aerodynamic Coefficients and Stability Derivatives for Truss-Braced Wing Aircraft Using OpenVSP
… weight carrying capabilities and aircraft stability for long and medium range missions. The incorporation of flight dynamics at the conceptual design stage offers enhanced aerodynamic performance and wing flexibility for the aircraft. A robust flight dynamic system would need a detailed …
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An investigation of the feasibility of a method of obtaining data from which the stability derivatives Cm
Thesis (B.S.) Massachusetts Institute of Technology. Dept. of Aeronautical Engineering, 1957.
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A theory and method of predicting the stability derivatives Clᵦ, Clᵣ, Cn𝗉, and CY𝗉 for wings of arbitrary planform in subsonic flow
… change drawn, for the estimation of certain stability derivatives for wings of arbitrary platform in subsonic flow.
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Simultaneous identification of short period and phugoid stability parameters using an advanced maximum likelihood method
… of obtaining the short period and phugcid stability derivatives from one maneuver, "simultaneously". It was concluded that the maximum likelihood identification program SCIDNT I showed great promise in obtaining the short period and phugoid stability derivatives from one maneuver. …
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Estimation of Air Flow Angles Derived from an Inertial Navigation System
… angle estimates to determine essential aircraft stability derivatives. Initial values for these stability derivatives are inaccurate but, over a short period of time, the Kalman Filters are able to converge to an accurate solution, provided the necessary parameters are made observable by aircraft …
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An analysis of curved flow wind tunnel testing
… curved flow as a method of obtaining dynamic stability derivatives is presented including an analysis of the flows involved in the curved flow wind tunnel and in curved flight. Equations for the forces and moments for each of these flows are presented and then used to develop equations for the …
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Aerodynamic Modeling Using Computational Fluid Dynamics and Sensitivity Equations
… (including angular rates). In particular, the stability derivatives are associated with partial derivatives of these functions. These stability derivatives can be computed using finite differences or the sensitivity equation method.
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Control Power Optimization using Artificial Intelligence for Forward Swept Wing and Hybrid Wing Body Aircraft
… deflections. Another method was developed using stability derivatives. This new method provided better results, and the computational time was reduced by two orders of magnitude. A hybrid scheme combining both methods was also developed to provide a real-time estimate of the optimum control …
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The prediction of aerodynamic force and moment coefficients on elliptic cone bodies at both angle of attack and sideslip by use of Newtonian impact theory
… for the aerodynamic coefficients and static stability derivatives were obtained. Expressions for the full and half conic bodies were given and approximate expressions were given for the half cone case. The circular cone results were obtained as a special case of the general results. …
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An investigation of the dynamic lateral stability and control of a parawing vehicle
… aerodynamic factors affecting dynamic lateral stability and control. These unusual characteristics are due in large part to the fact that the center of gravity of parawing vehicles is located far below the parawing, whereas conventional aircraft usually have the vertical center-of-gravity …
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An analysis of the static and dynamic characteristics of a decoupled landing entry vehicle
… were the most effective in providing static stability. To evaluate the lateral-directional handling qualities, a ω<sub>Θ</sub>/ω<sub>d</sub> coupling parameter along with the parameter abs(Θ/β) were derived to be applicable during hypersonic entry. Equations were also derived for determining …
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Development of a Small Unmanned Aerial Vehicle Longitudinal Model for Future Flutter Testing
… preliminary values for the static and dynamic stability derivatives. The next step was to design flight experiments for the purpose of system identification. The system identification focused on obtaining the longitudinal model and available software tools were used to get comparative results. …
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Identification of an Unsteady Aerodynamic Model up to High Angle of Attack Regime
… (DyPPiR) model mount at Virginia Tech Stability Wind Tunnel are described and analyzed. The corresponding data reduction methods are developed on the basis of multirate digital signal processing techniques. Since the model is sting-mounted to the support system of DyPPiR, the Discrete …
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A dynamic model for aircraft poststall departure
… can also be applied to the generation of dynamic stability derivatives by analytically simulating forced oscillation test procedures.
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An Investigation of Unsteady Aerodynamic Multi-axis State-Space Formulations as a Tool for Wing Rock Representation
The objective of the present research is to investigate unsteady aerodynamic models with state equation representations that are valid up to the high angle of attack regime with the purpose of evaluating them as computationally affordable models that can be used in conjunction with the equations of …
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Micro air vehicle motion tracking and aerodynamic modeling
… were used to determine longitudinal and lateral stability derivatives. The neutral point, weather-vane stability and the dihedral effect showed some variation with different trim speeds (different angles of attack). In the gliding flights, the aerodynamic characteristics exhibited quasi-steady …