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Book Determination of the Stability and Control Derivatives of the NASA F A 18 Harv Using Flight Data

Download or read book Determination of the Stability and Control Derivatives of the NASA F A 18 Harv Using Flight Data written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-17 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report documents the research conducted for the NASA-Ames Cooperative Agreement No. NCC 2-759 with West Virginia University. A complete set of the stability and control derivatives for varying angles of attack from 10 deg to 60 deg were estimated from flight data of the NASA F/A-18 HARV. The data were analyzed with the use of the pEst software which implements the output-error method of parameter estimation. Discussions of the aircraft equations of motion, parameter estimation process, design of flight test maneuvers, and formulation of the mathematical model are presented. The added effects of the thrust vectoring and single surface excitation systems are also addressed. The results of the longitudinal and lateral directional derivative estimates at varying angles of attack are presented and compared to results from previous analyses. The results indicate a significant improvement due to the independent control surface deflections induced by the single surface excitation system, and at the same time, a need for additional flight data especially at higher angles of attack. Napolitano, Marcello R. and Spagnuolo, Joelle M. Unspecified Center AIRCRAFT CONTROL; AIRCRAFT STABILITY; ANGLE OF ATTACK; F-18 AIRCRAFT; FLIGHT TESTS; LATERAL STABILITY; LONGITUDINAL STABILITY; MAXIMUM LIKELIHOOD ESTIMATES; PARAMETER IDENTIFICATION; AIRCRAFT MANEUVERS; CONTROL SURFACES; EQUATIONS OF MOTION; MATHEMATICAL MODELS; THRUST VECTOR CONTROL...

Book Determination of Stability and Control Derivatives from the NASA F a 18 Harv from Flight Data Using the Maximum Likelihood Method

Download or read book Determination of Stability and Control Derivatives from the NASA F a 18 Harv from Flight Data Using the Maximum Likelihood Method written by National Aeronautics and Space Adm Nasa and published by . This book was released on 2018-11-07 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report is a compilation of PID (Proportional Integral Derivative) results for both longitudinal and lateral directional analysis that was completed during Fall 1994. It had earlier established that the maneuvers available for PID containing independent control surface inputs from OBES were not well suited for extracting the cross-coupling static (i.e., C(sub N beta)) or dynamic (i.e., C(sub Npf)) derivatives. This was due to the fact that these maneuvers were designed with the goal of minimizing any lateral directional motion during longitudinal maneuvers and vice-versa. This allows for greater simplification in the aerodynamic model as far as coupling between longitudinal and lateral directions is concerned. As a result, efforts were made to reanalyze this data and extract static and dynamic derivatives for the F/A-18 HARV (High Angle of Attack Research Vehicle) without the inclusion of the cross-coupling terms such that more accurate estimates of classical model terms could be acquired. Four longitudinal flights containing static PID maneuvers were examined. The classical state equations already available in pEst for alphadot, qdot and thetadot were used. Three lateral directional flights of PID static maneuvers were also examined. The classical state equations already available in pEst for betadot, p dot, rdot and phi dot were used. Enclosed with this document are the full set of longitudinal and lateral directional parameter estimate plots showing coefficient estimates along with Cramer-Rao bounds. In addition, a representative time history match for each type of meneuver tested at each angle of attack is also enclosed. Napolitano, Marcello R. Unspecified Center...

Book Determination of the Stability and Control Derivatives of the F A 18 Harv from Flight Data Using the Maximum Likelihood Method

Download or read book Determination of the Stability and Control Derivatives of the F A 18 Harv from Flight Data Using the Maximum Likelihood Method written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-12-29 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research being conducted pertains to the determination of the stability and control derivatives of the F/A-18 High Alpha Research Vehicle (HARV) from flight data using the Maximum Likelihood Method. The document outlines the approach used in the parameter estimation (PID) process and briefly describes the mathematical modeling of the F/A-18 HARV and the maneuvers designed to generate a sufficient data base for the PID research. Napolitano, Marcello R. and Spagnuolo, Joelle M. NASA-CR-191216, NAS 1.26:191216 NCC2-759...

Book Flight Determined Subsonic Longitudinal Stability and Control Derivatives of the F 18 High Angle of Attack Research Vehicle  HARV  with Thrust Vectoring

Download or read book Flight Determined Subsonic Longitudinal Stability and Control Derivatives of the F 18 High Angle of Attack Research Vehicle HARV with Thrust Vectoring written by Kenneth W. Iliff and published by . This book was released on 1997 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Estimation of the Lateral directional Stability and Control Derivatives for the NASA F A 18 HARV with the Maximum Likelihood Method Using Kalviste s Dynamic Modeling

Download or read book Estimation of the Lateral directional Stability and Control Derivatives for the NASA F A 18 HARV with the Maximum Likelihood Method Using Kalviste s Dynamic Modeling written by Brad Alan Seanor and published by . This book was released on 1995 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Scientific and Technical Aerospace Reports

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

Book Monthly Catalogue  United States Public Documents

Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1995 with total page 1994 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Determination of Stability Derivatives from Flight Data Using a Newton Raphson Minimization Technique

Download or read book Determination of Stability Derivatives from Flight Data Using a Newton Raphson Minimization Technique written by Kenneth W. Iliff and published by . This book was released on 1971 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Flight Determined  Subsonic  Lateral Directional Stability and Control Derivatives of the Thrust Vectoring F 18 High Angle of Attack Research Vehicle  HARV   and Comparisons to the Basic F 18 and Predicted Derivatives

Download or read book Flight Determined Subsonic Lateral Directional Stability and Control Derivatives of the Thrust Vectoring F 18 High Angle of Attack Research Vehicle HARV and Comparisons to the Basic F 18 and Predicted Derivatives written by Kenneth W. Iliff and published by . This book was released on 1999 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Extraction of Lateral Directional Stability and Control Derivatives for the Basic F 18 Aircraft at High Angles of Attack

Download or read book Extraction of Lateral Directional Stability and Control Derivatives for the Basic F 18 Aircraft at High Angles of Attack written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-03 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of parameter identification to determine the lateral-directional stability and control derivatives of an F-18 research aircraft in its basic hardware and software configuration are presented. The derivatives are estimated from dynamic flight data using a specialized identification program developed at NASA Dryden Flight Research Center. The formulation uses the linearized aircraft equations of motions in their continuous/discrete form and a maximum likelihood estimator that accounts for both state and measurement noise. State noise is used to model the uncommanded forcing function caused by unsteady aerodynamics, such as separated and vortical flows, over the aircraft. The derivatives are plotted as functions of angle of attack between 3 deg and 47 deg and compared with wind-tunnel predictions. The quality of the derivative estimates obtained by parameter identification is somewhat degraded because the maneuvers were flown with the aircraft's control augmentation system engaged, which introduced relatively high correlations between the control variables and response variables as a result of control motions from the feedback control system. Iliff, Kenneth W. and Wang, Kon-Sheng Charles Armstrong Flight Research Center RTOP 505-68-50...

Book Stability Derivative Determination from Flight Data

Download or read book Stability Derivative Determination from Flight Data written by Chester H. Wolowicz and published by . This book was released on 1958 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive discussion of the various factors affecting the determination of stability and control derivatives from flight data is presented. Factors relating to test techniques, determination of mass characteristics, instrumentation, and methods of analysis are discussed. For most longitudinal-stability-derivative analyses simple equations utilizing period and damping were found to be as satisfactory as more comprehensive methods. The graphical time-vector method was the basis of lateral-derivative analysis, although simple approximate methods can be useful if applied with caution. Control effectiveness was generally obtained by relating the peak acceleration to the rapid control input, and consideration must be given to aerodynamic contributions if reasonable accuracy is to be realized. Because of the many factors involved in the determination of stability derivatives, it is believed that the primary stability and control derivatives are probably accurate to within 10 to 25%, depending upon the specific derivative. Static-stability derivatives at low angle of attack show the greatest accuracy. (Author).

Book Results from F 18b Stability and Control Parameter Estimation Flight Tests at High Dynamic Pressures

Download or read book Results from F 18b Stability and Control Parameter Estimation Flight Tests at High Dynamic Pressures written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-13 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: A maximum-likelihood output-error parameter estimation technique has been used to obtain stability and control derivatives for the NASA F-18B Systems Research Aircraft. This work has been performed to support flight testing of the active aeroelastic wing (AAW) F-18A project. The goal of this research is to obtain baseline F-18 stability and control derivatives that will form the foundation of the aerodynamic model for the AAW aircraft configuration. Flight data have been obtained at Mach numbers between 0.85 and 1.30 and at dynamic pressures ranging between 600 and 1500 lbf/sq ft. At each test condition, longitudinal and lateral-directional doublets have been performed using an automated onboard excitation system. The doublet maneuver consists of a series of single-surface inputs so that individual control-surface motions cannot be correlated with other control-surface motions. Flight test results have shown that several stability and control derivatives are significantly different than prescribed by the F-18B aerodynamic model. This report defines the parameter estimation technique used, presents stability and control derivative results, compares the results with predictions based on the current F-18B aerodynamic model, and shows improvements to the nonlinear simulation using updated derivatives from this research. Moes, Timothy R. and Noffz, Gregory K. and Iliff, Kenneth W. Armstrong Flight Research Center RTOP 529-61-14

Book Stability and Control Estimation Flight Test Results for the SR 71 Aircraft With Externally Mounted Experiments

Download or read book Stability and Control Estimation Flight Test Results for the SR 71 Aircraft With Externally Mounted Experiments written by Timothy R. Moes and published by . This book was released on 2002 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: A maximum-likelihood output-error parameter estimation technique is used to obtain stability and control derivatives for the NASA Dryden Flight Research Center SR-71A airplane and for configurations that include experiments externally mounted to the top of the fuselage. This research is being done as part of the envelope clearance for the new experiment configurations. Flight data are obtained at speeds ranging from Mach 0.4 to Mach 3.0, with an extensive amount of test points at approximately Mach 1.0. Pilot-input pitch and yaw-roll doublets are used to obtain the data. This report defines the parameter estimation technique used, presents stability and control derivative results, and compares the derivatives for the three configurations tested. The experimental configurations studied generally show acceptable stability, control, trim, and handling qualities throughout the Mach regimes tested.