System identification and dynamics modeling of a distributed electric propulsion aircraft

Flight testing of a 21%-scale Cirrus SR22T distributed electric propulsion aircraft has been performed at the University of Illinois at Urbana-Champaign with a goal of identifying the influence of distributed propulsion units on the aircraft’s flight dynamics. A linear state-space model was formulated to describe the aircraft’s longitudinal motion and to serve as a baseline model for comparisons with more complicated methods of modeling aero-propulsive coupling effects. Unknown model parameters were identified from flight test data using frequency-domain system-identification methods, and the resultant model was validated against an in-dependently-acquired set of flight data. Results gave confidence in the flight testing and system identification methods, and provided a solid baseline model as a basis for comparison in future studies.