X-HALE: A Very Flexible Unmanned Aerial Vehicle for Nonlinear Aeroelastic Tests

The University of Michigan has designed and built an unmanned aerial vehicle denoted X-HALE, which is aeroelastically representative of very flexible aircraft. The objective of this test bed is to collect unique data of the geometrically nonlinear aeroelastic response coupled with the flight dynamics to be used for future code validation. The aircraft presents specific aeroelastic features (e.g., coupled rigid/elastic body instability, large wing deflection during gust) that can be measured in flight. Moreover, the airframe construction choice is such that the elastic, inertial, and geometric properties can be well characterized. These are requirements driven by the need of the collected data to be used to support validation of coupled nonlinear aeroelastic/flight dynamics codes.