Identification of helicopter rigid body dynamics from flight data

This paper discusses helicopter modeling and identification related aspects. By applying the system identification methodology, longitudinal, and lateral-directional rigid body helicopter dynamics are identified from flight data. Aerodynamic parameters from single input excitation, as well as multimaneuver evaluation, are estimated utilizing output-error approach. The formulated mathematical models yield adequate fits to measured time histories. Results obtained from the proof-of-match for model validation indicate that the identified derivatives can satisfactorily predict longitudinal dynamics to a given arbitrary input. It is further demonstrated that lateral body dynamics can be adequately predicted by including cross-coupling terms in the estimation model