On 11 December 2006, a Boeing 747SP being operated by Syrian Air on a scheduled passenger flight from Damascus to Stockholm was arriving on the designated parking gate at destination in normal visibility at night when it collided with the airbridge. None of the 116 occupants of the aircraft suffered any injury but the aircraft was “substantially damaged” and the airbridge was “damaged”.
An Investigation was carried out by the Swedish Accident Investigation Board. It was established that the Docking Guidance System had been wrongly programmed to display flight crew guidance for a standard length 747, which has two passenger doors forward of the wing, rather than the shorter SP version which has only a single door forward of the wing. The airbridge operator reported being unfamiliar with the aircraft variant code which was correctly indicated at the control panel. It was noted that although some gates at the airport were at the time of the accident already equipped with a modification which provided an automatic alert if the aircraft type entered was incorrect, the gate allocated to the accident aircraft was not one of these. It was also noted that the emergency stop button had been activated by ramp staff just before impact occurred but not in time to prevent the top of the left wing striking the underside of the airbridge which resulted in a large hole being torn in the upper surface of the wing.
The aircraft commander observed that it was not unusual to encounter a gate displaying the generic display ‘B747’ which was in fact set correctly for the shorter B747SP. The investigation found that “proficiency in the different (aircraft) type versions was not included in the (air bridge) operator’s training”. It was also noted that Safety Recommendations made to the Swedish CAA as a result of the investigation into a similar accident ten years earlier in which the same aircraft type had also collided with a mis-positioned airbridge at the same airport see B74S, Stockholm Arlanda Sweden, 1996.
The Investigation concluded that:
“the accident was caused by an inadequate training programme and deficient safety guidance in respect of the gate operator’s handling of the docking system.”
It also concluded that a Contributory Factor was that “safety shortcomings that had been pointed out earlier had not been rectified.”
The Final Report of the Investigation was published on 19 December 2007 and may be seen in full at SKYbrary bookshelf: Swedish AIB Report RL 2007:23e
Four Safety Recommendations were made as a result of the Investigation, all to the Swedish Civil Aviation Authority which was recommended to:
- Work with the airport to ensure that work for that proficiency in different versions of aircraft types is introduced into the training syllabus for gate operators. (RL 2007:23e R1)
- Ensure that a relevant safety and quality control system for airbridge operators and (their use of) guidance systems for docking aircraft is present. (RL 2007:23e R2)
- Ensure that the gates concerned at Arlanda airport are equipped with updated docking systems that can distinguish between different versions of the same aircraft type. (RL 2007:23e R3)
- Work for to ensure that all docking terminals at Arlanda airport are designed in a way that information regarding aircraft types and type versions cannot be misinterpreted. (RL 2007:23e R4)