B738 / B738, Seville Spain, 2012

B738 / B738, Seville Spain, 2012

Summary

On 13 April 2012 a Boeing 737-800 being taxied off its parking stand for a night departure by the aircraft commander failed to follow the clearly and correctly marked taxi centrelines on the well-lit apron and instead took a short cut towards the taxiway centreline which resulted in the left winglet striking the left horizontal stabiliser and elevator of another Ryanair aircraft correctly parked on the adjacent stand causing damage which rendered both aircraft unfit for flight. The pilot involved was familiar with the airport and had gained almost all his flying experience on the accident aircraft type.

Event Details
When
13/04/2012
Event Type
GND, HF
Day/Night
Night
Flight Conditions
On Ground - Normal Visibility
Flight Details
Operator
Type of Flight
Public Transport (Passenger)
Intended Destination
Take-off Commenced
No
Flight Airborne
No
Flight Completed
No
Phase of Flight
Taxi
Flight Details
Operator
Type of Flight
Public Transport (Passenger)
Intended Destination
Take-off Commenced
No
Flight Airborne
No
Flight Completed
No
Phase of Flight
Parked
Location
Location - Airport
Airport
General
Tag(s)
Aircraft-aircraft collision
HF
Tag(s)
Flight Crew / Ground Crew Co-operation, Ineffective Monitoring, Procedural non compliance
GND
Tag(s)
Taxiway collision, Wingtip clearance
Outcome
Damage or injury
Yes
Aircraft damage
Minor
Non-aircraft damage
Yes
Non-occupant Casualties
No
Off Airport Landing
Yes
Ditching
Yes
Causal Factor Group(s)
Group(s)
Aircraft Operation
Safety Recommendation(s)
Group(s)
None Made
Investigation Type
Type
Independent

Description

On 13 April 2012, in normal ground visibility at night, a Boeing 737-800 on a scheduled passenger flight from Seville to Gran Canaria was leaving its parking stand when it was in collision at taxi speed with another Boeing 737-800 parked on the adjacent stand fully boarded but with doors still open pending a departure to Tenerife South. Both aircraft were damaged sufficiently make them unfit for flight but there were no injuries. All occupants onboard both aircraft were disembarked and returned to the terminal.

Investigation

An Investigation was carried out by the Spanish AIB, CIAIAC. The Investigation made use of both the DFDR and Cockpit Voice Recorder (CVR) recordings of the moving aircraft involved as well as the accounts of the crew of that aircraft and the ramp coordinator allocated to its turnround.

It was established that the first 737 had begun taxiing from Stand R10 (see the diagram below) in accordance with the issued taxi clearance for an on-time departure with the aircraft commander as PF. Initially, a right turn had been made following the marked taxi line leading to the adjacent taxiway G8. However, the aircraft had then turned to the left directly towards the taxiway centreline prematurely because the taxiing pilot believed that their aircraft left wing would thereby remain clear of the stationary aircraft on stand R11. This belief turned out to be flawed and the left winglet of the moving aircraft subsequently hit the left horizontal stabiliser and elevator of the other aircraft. Post impact, a “stop” signal was given to the aircraft by the ramp coordinator and seen by the pilot who then stopped the aircraft.

Stands R10 and R11 showing the marked taxi centrelines required for use of R10 in yellow (reproduced from the Official Report)

It was found that the taxiing pilot was familiar with the parking area involved because of previous visits and had gained almost all of their flying experience on the aircraft type involved, although the majority of that time would have been spent as a First Officer. The ramp co-ordinator was found to have been relatively inexperienced but appropriately trained for their role which included, amongst various other duties, monitoring the movement of the aircraft arrival on and departure from stand for an allocated turnround with reference to potential obstructions.

The Investigation noted that both Ryanair and their contracted Handling Agent at Seville had Ground Operations Manuals which when compared in respect of signalling relevant to the collision, were found to be “similar… in terms of the symbols and indications used”. From the statements provided to the Investigation, it appeared possible that the commander may have missed and/or misinterpreted signalling from the ramp co-ordinator prior to the impact and/or that the ramp coordinator, having been surprised by the sudden and unexpected deviation from the taxi out line whilst monitoring the wing tip clearance of the departing aircraft from a position near to the tail of the other aircraft and signalled accordingly, may not have given the correct pre-impact stop signal.

It was found that the Operator’s FCOM included explicit instructions in respect of taxi procedures to the effect that any applicable taxi line must be followed with the nose wheels and that corners must not be cut.

The Cause of the investigated event was determined as “(the departing aircraft) not following the turning line all the way out of parking stand R10".

The Final Report was approved on 29 April 2013 and subsequently made available in English translation. No Safety Recommendations were made and no Safety Action by parties to the event was reported.

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