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

Author: National Aeronautics and Space Adm Nasa

Publisher:

Published: 2018-11-07

Total Pages: 102

ISBN-13: 9781730938672

DOWNLOAD EBOOK

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...

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

Author: National Aeronautics and Space Adm Nasa

Publisher: Independently Published

Published: 2018-12-29

Total Pages: 28

ISBN-13: 9781792079962

DOWNLOAD EBOOK

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...

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

Author: National Aeronautics and Space Administration (NASA)

Publisher: Createspace Independent Publishing Platform

Published: 2018-07-17

Total Pages: 124

ISBN-13: 9781723022715

DOWNLOAD EBOOK

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...