Boeing X-53 Active Aeroelastic Wing

The X-53 Active Aeroelastic Wing (AAW) was an American research project that was undertaken jointly by the Air Force Research Laboratory (AFRL), Boeing Phantom Works and NASA's Dryden Flight Research Center, where the technology was flight tested on a modified McDonnell Douglas F/A-18 Hornet. Active Aeroelastic Wing Technology is a technology that integrates wing aerodynamics, controls, and structure to harness and control wing aeroelastic twist at high speeds and dynamic pressures.

Source: Wikipedia — Boeing X-53 Active Aeroelastic Wing (CC BY-SA 4.0)