What happened
While taxiing on the tarmac, the flight crew of a B717 determined that a non-standard taxi path was required to allow two other B717 aircraft to pass. This manoeuvre was prompted by constraints on the tarmac and the arrival of an inbound aircraft. During this movement, the aircraft's tail came into proximity with the tail of a parked F100.
The investigation
The investigation examined the circumstances surrounding the movement and the lack of ground support. It was noted that no wing walker was positioned on the tarmac to provide the crew with timely warnings regarding the proximity of the F100 or to facilitate verbal communication regarding taxi intentions. The crew was preparing to request a wing walker when an engineer from a different company approached the aircraft.
Although the engineer provided a standard hand signal, the crew interpreted the thumbs up gesture as an indication that both the wing tip and the tail were clear of all obstacles. There had been no prior communication between the crew and the engineer before this signal was given. Furthermore, the engineer did not expect the aircraft to execute a sharp right turn after passing the F100, and their position prevented them from warning the crew once the turn had begun.
Findings
- The crew was unaware of the arrival of the inbound B717 until after the taxi manoeuvre had already started.
- A ground handling agent wing walker was not present to assist the crew during the non-standard taxi.
- The crew's interpretation of a hand signal as meaning the entire aircraft was clear contributed to the incident, as the signal did not account for the tail's position during the subsequent turn.