Bell V-280 Hover Flight Dynamics Model Validation and Update with Flight Test Data

Abstract

Flight dynamics simulation models are a key tool for enabling modern flight control design; however, advanced configurations such as the Bell V-280 Valor tiltrotor proposed for the U.S. Army Future Long Range Assault Aircraft program require advancements in existing flight dynamics models. This work uses flight test data to validate the accuracy of V-280 flight dynamics models of various levels of fidelity including a low fidelity Froude scale model, a physics based simulation model, and a high fidelity system integration lab. Model fidelity in hover is assessed using system identification including the Joint Input-Output method to extract frequency responses from flight test data and subsequently identify a state space model with respect to individual redundant control effectors. The identification results from flight test data are then used to update a physics-based model comparing two different update approaches: a simple gain and time delay correction versus a more complex force and moment increment correction. The implementation complexity as well as benefits and limitations for both methods are examined for the V-280.