US Patent 12129018 Active drag control system for an aircraft

An aircraft includes an active drag control system such as a Laminar Flow Control (LFC) system having a port LFC apparatus and a starboard LFC apparatus. The aircraft has a control system to test how efficiently the LFC system is working by differentially operating the port LFC apparatus and the starboard LFC apparatus, for example by deactivating either LFC apparatus, and measuring the effect on the direction of flight of the aircraft. The control system also can change the direction of the aircraft, and trim the aircraft, by differentially operating the port LFC apparatus and the starboard LFC apparatus.