Aerodynamic Modeling and System Identification from Flight Data-Recent Applications at DLR

his lecture provides an overview of system identification activities carried out during the last decade at DLR, the German Aerospace Center. After a brief account of parameter estimation methods and of consistency checking of recorded flight data, an emphasis is placed on aerodynamic modeling from flight data. Several applications are presented, such as: i) development of global, high-fidelity aerodynamic databases for training simulators, ii) models for in-flight simulator iii) modeling of stall hysteresis, iv) estimation of aerodynamic flow field characteristics and validation of aircraft reaction models from wake vortex encounter flights, and v) a parametric wake distortion model to improve helicopter coupling off-axis response. These examples cover a variety of flight vehicles with widely different characteristics. Besides parameter estimation aspects, those related to model validation and update of aerodynamic databases are discussed. The talk is concluded by indicating the possible future directions of work.