What happened
On 27 July 2007, a collision occurred between a Boeing 777-236, registration G-VIIK, and an Airbus A321-231, registration G-EUXH, at London Heathrow Airport. The Airbus had recently arrived from Zurich and had taxied to Stand 431. However, because the electronic Stand Entry Guidance (SEG) system had not been activated by ground staff, the crew stopped the aircraft approximately 50 metres short of the intended position, leaving the rear of the plane protruding into the adjacent taxiway.
Shortly after, the crew of the G-VIIK requested pushback from Stand 429. During the maneuver, the left wing of the Boeing 777 struck the vertical fin of the stationary Airbus. The impact caused damage to the Airbus's fin and fairings, and a one-metre section of the Boeing's left aileron became embedded in the Airbus's fin lower fairing. There were no fatalities and no injuries to the passengers or crew on either aircraft.
The investigation
The AAIB investigation established that the pushback crew for the G-VIIK consisted of a tug driver and a headset operator. The headset operator remained inside the tug cab for most of the operation due to a tangled headset lead. Because the driver's view was restricted, he relied on the headset operator to monitor the area. The investigation also found that the Airbus crew had attempted to notify Ground Movement Control (GMC2) that the stand guidance was not active, but the radio frequency was too busy for the call to be acknowledged.
Furthermore, the investigation examined the working patterns of the ground crew, noting that both individuals had worked significant overtime, with one crew member having completed four consecutive double shifts. The investigation also reviewed the operator's safety management system, finding that recurrent safety awareness training for ground staff had been discontinued.
Findings
- The primary cause of the accident was that the G-VIIK pushback was not performed according to the operator's standard operating procedures or safe practices.
- The headset operator's decision to remain in the tug cab prevented him from adequately monitoring the aircraft's clearance.
- The tug driver's view of the conflicting aircraft was significantly limited by the vehicle's design and position.
- The Airbus was positioned in a way that partially obstructed the taxiway because the stand guidance system had not been activated.
- Organizational issues, including the lack of recurrent safety training and incomplete risk assessments regarding aircraft stopped short of stands, contributed to the event.
- Potential fatigue due to excessive working hours and irregular shifts may have impacted the performance of the ground crew.