A320 Rolls Back on Stand: Incomplete Maintenance Procedures and Ground Handling Deviations
The UK Air Accidents Investigation Branch (AAIB) has reported on a case where parked EasyJet Airbus A32o-214 G-EZTM rolled back and struck ground equipment on Stand 559 at London Gatwick airport on 26 March 2017.
The flight crew had boarded the aircraft prior and completed cockpit preparation (including confirming the parking brake was ON). However, a brake system defect, which had occurred on the previous sector, was also being investigated while the aircraft was parked.
As part of this process, Aircraft Maintenance Manual (AMM) Task 32-42-00-710-001-A Rev.55 was being actioned. This required the parking brake to be selected OFF. On completion of the task it remained in the OFF position, as there was no requirement in the task to select the parking brake ON again.
This is a classic poor procedure that fails to return the aircraft to a safe state on completion.
The flight crew were unaware the brake was now OFF.
The AAIB make no comment on the liaison between maintenance personnel and flight crew.
Prior to departure, with the forward steps still in position, the ground handling staff arrived and connected a tug, before removing the chocks as part of their pre-departure checks.
However, the operator’s procedures required chocks to remain in place until all ground equipment is clear of the aircraft.
The tug driver then realised the tug radio was not working and disconnected the tug to replace it with a fully serviceable one. There was no communication with the flight crew at this point.
Unconnected from the tug, unchocked and with the brakes OFF, the aircraft was now free to roll backwards, which it did. The flight crew noticed the movement and applied the footbrakes but not before the aircraft struck the steps, damaging the fuselage and Door 1L. There were no injuries to the 168 persons on board or ground staff.
The operator’s engineering department is reviewing the AMM task (32-42-00-710-001-A Rev.55) and will make recommendations to the aircraft manufacturer to amend the AMM accordingly.
The ground handling company:
- Raised awareness of the event;
- Retrained the staff involved concerning the correct chocking procedures;
- The defective equipment local operating procedure has been reissued to all staff to prevent inoperative equipment being available for use.
A classic example of ‘all the holes’ lining up at once, noticeably at the interfaces between multiple teams.
Aerossurance is pleased to be supporting the annual Chartered Institute of Ergonomics & Human Factors’ (CIEHF) Human Factors in Aviation Safety Conference for the third year running. We will be presenting for the second year running too. This year the conference takes place 13 to 14 November 2017 at the Hilton London Gatwick Airport, UK with the theme: How do we improve human performance in today’s aviation business?