A ground state determination system for an aircraft includes sensors configured to detect parameters of the aircraft and a flight control system implementing a ground state module. The ground state module includes a ground state monitoring module configured to monitor the parameters and a ground state determination module configured to compare each of the parameters monitored by the ground state monitoring module to a respective parameter threshold to determine whether the aircraft is on a surface.

One aspect is a flight control system for a coaxial rotary wing aircraft including a main rotor system and an active elevator. The flight control system includes a flight control computer with processing circuitry that executes control logic. The control logic includes a gust detector that produces a gust error indicative of a wind gust encountered by the coaxial rotary wing aircraft. The control logic also includes a gust alleviation control that reduces lift on the main rotor system with collective, based on the gust error, and mixes a collective command to a main rotor cyclic and a differential cyclic to reduce an aircraft pitch response and a lift-offset change. The gust alleviation control also reduces a main rotor pitching moment with the main rotor cyclic, based on the gust error, and mixes a main rotor cyclic command to the active elevator to reduce the aircraft pitch response.