COMPARISON OF PARAMETER ESTIMATION RESULTS FROM FLIGHT TEST DATA USING LINEAR AND NONLINEAR MAXIMUM LIKELIHOOD METHODS.

Guidelines for evaluation of flight test data with respect to aircraft aerodynamic performance and characteristics are given. A comparison has been made for parameter estimation results from flight test data using a linear and a general nonlinear maximum likelihood method. The successful application of the nonlinear ML method to data compatibility checking and to correction of measurement data has been demonstrated. Five different aircraft system equation models, utilizing various sets of dimensional or nondimensional aircraft coefficients, were developed for use in the parameter estimation.