An air active control aircraft having an air three-dimensional true airspeed detection system composed of an air data sensor probe in the form of a truncated pyramid-shape Pitot probe and an air flight velocity operation processor for calculating an air flight velocity vector from three-dimensional air pressure information detected by the air data sensor probe, airframe motion detection sensors for detecting an airframe motion, and an on-board control computer for generating a flight control law. The on-board control computer inputs an air flight velocity vector signal obtained from the air flight velocity vector device into a control-surface control system in parallel with airframe motion detection sensor signals, and presumes a flight motion induced by a change in air to generate the flight control law for quickly carrying out air flight stability control.