Vehicle Modeling for Flight Test Measurements of Ship Airwake Disturbances

This paper describes modeling of small-scale rotorcraft using system identification and first-principles techniques. The vehicle model is used as part of a methodology to empirically validate coupled ship airwake and rotor wake computational fluid dynamics disturbance models used in Virtual Dynamic Interface (VDI) simulations with flight test data. The validation approach uses a gust identification algorithm to estimate disturbance characteristics from flight data. The algorithm uses a model of the aircraft dynamics, and therefore, accurate models of system dynamics are desirable. Several vehicles are being used to help validate the gust identification algorithm: the Hornet-Mini, a single-shaft remote control scale helicopter and the Iris+ quadrotor. This report summarizes work to estimate dynamic models of these vehicles with the AUSPEX and CIFER tools.