Identification of the Aerodynamic Model of the DLR Research Aircraft ATTAS from Flight Test Data.

Abstract

Determination of the aerodynamic characteristics of the ATTAS aircraft from flight test data is of considerable importance for many of the research projects pursued at the DLR. The report provides the details of flight tests carried out for this purpose. The data checking is based on the kinematic equations of aircraft motion. The estimation of aerodynamic derivatives is carried out from the coupled equations of aircraft motion. For both of these purposes the maximum likelihood estimation method is employed. The details of mass characteristics data are provided along with other aircraft installation-dependent data required for a parameter estimation. The report provides the results of kinematic consistency checking and the aerodynamic derivatives at typical flight conditions, and attempts to derive a combined model valid over a wider range of speed variations.