C4/2004L Taxiing damage at Helsinki-Vantaa airport on 18 December 2004

On 18 December 2004, an incident occurred at Helsinki-Vantaa airport when a turbo-propeller aircraft collided its tail with another aircraft. The incident took place during a power push-back procedure, where the aircraft uses its own engines to push out from a parking stand. The other aircraft was parked empty in a stand behind the reversing aircraft. In its decision C 4/2004 L, the Accident Investigation Board Finland decided to conduct an investigation into the incident. Air Accident Investigator Hannu Melaranta was nominated as an investigator-in charge and Investigator Tapani Vänttinen as a member of the investigation commission.

The reversing aircraft was an ATR 72-201 and the parked aircraft was an MD-82. The ATR was departing to a scheduled flight and the crew intended to perform a power push-back procedure to a position where they would have been able to start normal taxiing. A ramp foreman was standing outside the aircraft and he was in charge of the push-back. He was giving hand signals to the crew in order to guide them in manoeuvring the aircraft (marshalling). The aircraft failed to stop in a correct position and consequently collided with another aircraft behind. Both aircraft sustained minor damages.

The investigation revealed that the taxiline paintings on the apron were inadequate, and that the pilots were not properly informed about the abnormal taxiway arrangements, which were in force in the apron due to construction works at the time of the incident. Furthermore, the ramp foreman did not use correct hand signals when marshalling the aircraft and the instructions concerning the procedures and responsibilities during power push-back were ambiguous. In addition, there were no instructions concerning these procedures in the aircraft’s operating manual.

The probable cause for the incident was, that the flight crew did not receive a stopping signal from the marshaller, nor did they make initiative to stop the aircraft in correct position, because the taxiline paintings were not visible to the marshaller’s position or to the cockpit. A contributing factor was the fact that there were different views about the responsibility for stopping the aircraft among the pilots and the ramp workers, which interfered with the instructions.

The investigation commission issued one safety recommendation. Finnair Oyj should include a description of the power push-back procedure in its operation manuals. This description should be available to all personnel involved in a push-back procedures.

C4/2004L Report (pdf, 0.5 Mt)