What happened
On June 16, 2015, a Beechcraft 200GT Super King Air was performing ground operations at Warsaw Chopin Airport (EPWA). The pilot received taxi instructions from the ground controller (GND) to proceed via taxiway "W" and taxiway "A0", with a subsequent plan to taxi along runway 15.
Following the instruction, the ground controller handed the aircraft over to the tower controller (TWR) for communication. Shortly after this handover, the controller observed that the pilot of the Beechcraft 200GT Super King Air had turned onto taxiway "A1", which was closed to taxiing operations.
To resolve the situation, the ground controller dispatched a "Follow me" vehicle to assist the pilot in safely navigating the aircraft out of the closed taxiway.
The investigation
The PKBWL investigation focused on the sequence of ground movements and the adherence to air traffic control instructions. The investigation established that the aircraft deviated from the assigned route provided by the ground controller.