Introduction
On August 5, 2020, at 04:34 UTC, a serious incident occurred at Sofia Airport, Bulgaria, involving an Airbus A320-232 aircraft, registration HA-LWH, operated by Wizz Air Hungary Ltd. The aircraft was preparing for flight W64331 from Sofia to Dortmund. The incident involved a self-propelled passenger stair that struck the aircraft's left wing during ground handling.
Incident Description
During the final phase of ground services, after passenger embarkation, the driver of a self-propelled passenger stair began moving away from the aircraft. While manoeuvring around the aircraft, the stair hit the left wing approximately 0.5 to 0.6 metres from the wingtip. The impact caused damage to the wing, preventing the flight from being performed. The flight was subsequently cancelled, and passengers were returned to the terminal.
Aircraft and Operator Information
The aircraft was an Airbus A320-232 with registration HA-LWH, operated by Wizz Air Hungary Ltd. The flight was a scheduled commercial passenger transport from Sofia Airport to Dortmund Airport. Ground handling services were provided by Gold Air Handling.
Damage and Consequences
The left wing of the aircraft sustained damage. No consequences were reported for the flight crew, passengers, or ground handling crew. There were no injuries. The damage necessitated cancellation of the flight.
Causes
According to the investigation by the Air, Maritime and Railway Accident Investigation National Board (AMRAINB), the serious incident resulted from a main cause and a contributing factor. The main cause was violations of the technology during ground handling of the aircraft service by the passenger stair driver when leaving the aircraft stand. The stair was allowed to manoeuvre below the minimum permissible safe distance from the aircraft. The contributing factor was insufficient concentration of the ground support equipment driver's attention due to fatigue.
Investigation
The occurrence was classified as a serious incident. An investigation commission was appointed. Factual information was gathered from written explanations from flight crew, ground crew, witnesses, data from BULATSA, and video cameras at Sofia Airport.