Manned Test Flights of Morphing Flaps for High-Dynamic Direct Lift Control

Atmospheric turbulence remains a major challenge for flight comfort, safety, and efficiency, motivating the development of fast active systems to suppress turbulence loads. This study presents the first manned flight investigation of high-dynamic camber morphing flaps for Direct Lift Control, combining both technologies toward the long-term goal of enabling turbulence-suppressed aviation. A pair of 2.2 m span morphing flaps, capable of ±10° dynamic deflection via an internal rotary drive system, is integrated into a one-seater experimental aircraft. Test flights at speeds between 120 and 180 km/h are conducted using sinusoidal and step excitations, and the aircraft response is evaluated from inertial measurements. Results show a linear relationship between flap deflection, quadratic airspeed, and generated lift, confirming theoretical expectations. The system promises a peak lift of 0.85 g at maximum airspeed and exhibits high temporal responsiveness, reaching 0.4 g within 30 ms. Additional effects, including wing–tail aerodynamic coupling and pilot-induced damping, are observed. Overall, the findings demonstrate the feasibility and effectiveness of high-dynamic morphing flaps for manned Direct Lift Control applications and highlight their strong potential for future turbulence suppression, gust load alleviation, and active flight-path control.