What happened
On 20 December 2019, a Boeing 747-436, registration G-CIVU, was taxiing to its parking position at London Heathrow Airport's Terminal 3. The aircraft was arriving during heavy rain and dark conditions. As the aircraft approached Stand 331, it collided with a fuel transfer vehicle (FTV) that had remained on the stand after completing a previous refuelling task.
The collision occurred while the aircraft was maneuvering into its final position. The driver of the FTV was focused on resolving a technical issue with a frozen tablet computer and, due to wearing ear defenders and facing away from the aircraft, was unaware of the approaching Boeint 747-436. The impact caused damage to the No 1 engine cowl of the aircraft and the rear of the FTV. There were no fatalities and no injuries to the 17 crew members or 328 passengers on board.
The investigation
The AAIB examined the actions of the flight crew, ground staff, and the vehicle driver. The investigation established that the stand guidance system had been activated, which led the flight crew to believe the stand was clear. However, the investigation found that the ground staff's responsibilities were poorly defined when two supervisors were assigned to a single arrival.
One supervisor had walked the centreline to check for foreign object debris but did not confirm the stand was clear of vehicles. The second supervisor, positioned at the guidance control panel, activated the system after seeing his colleague on the line, assuming the check was complete. Crucially, the investigation found that the position of the jetty and other parked equipment made it impossible for the supervisor at the control panel to see the right side of the stand where the FTV was located.
Findings
- The collision was caused by the failure of both the flight crew and ground staff to identify the FTV on the stand.
- Adverse weather, including heavy rain, darkness, and glare from terminal lights, significantly reduced visibility for the pilot.
- The FTV driver was distracted by a malfunctioning tablet and was unable to hear the approaching aircraft due to ear defenders.
- Ground handling procedures were inconsistent, with conflicting instructions regarding whether a full centreline walk was required.
- The stand guidance system was activated despite the presence of an obstruction because the supervisor's view was obscured by terminal infrastructure.