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B738/B763, Barcelona Spain, 2011

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Summary
On 14 April 2011, a Ryanair Boeing 737-800 failed to leave sufficient clearance when taxiing behind a stationary Boeing 767-300 at Barcelona and the 737 wingtip was in collision with the horizontal stabiliser of the 767, damaging both. The 767 crew were completely unaware of any impact but the 737 crew realised the ‘close proximity’ but dismissed a cabin crew report that a passenger had observed a collision. Both aircraft completed their intended flights without incident after which the damage was discovered, that to the 767 requiring that the aircraft be repaired before further flight.
Event Details
When April 2011
Actual or Potential
Event Type
Ground Operations, Human Factors
Day/Night Day
Flight Conditions On Ground - Normal Visibility
Flight Details
Aircraft BOEING 737-800
Operator Ryanair
Domicile Ireland
Type of Flight Public Transport (Passenger)
Origin Barcelona/El Prat Airport
Intended Destination Ibiza Airport
Actual Destination Ibiza Airport
Take off Commenced Yes
Flight Airborne Yes
Flight Completed Yes
Flight Phase Taxi
TXI
Flight Details
Aircraft BOEING 767-300ER
Operator American Airlines
Domicile United States
Type of Flight Public Transport (Passenger)
Origin Barcelona/El Prat Airport
Intended Destination New York/John F Kennedy International Airport
Actual Destination New York/John F Kennedy International Airport
Take off Commenced Yes
Flight Airborne Yes
Flight Completed Yes
Flight Phase Standing
STD
Location - Airport
Airport Barcelona/El Prat Airport
General
Tag(s) Aircraft-aircraft collision,
Event reporting non compliant,
Inadequate Aircraft Operator Procedures,
Inadequate ATC Procedures,
Inadequate Airport Procedures
HF
Tag(s) Flight / Cabin Crew Co-operation,
Inappropriate crew response - skills deficiency
GND
Tag(s) Taxiway collision,
Aircraft / Aircraft conflict,
Wingtip clearance
Outcome
Damage or injury No
Aircraft damage Minor
Causal Factor Group(s)
Group(s) Aircraft Operation,
Air Traffic Management
Safety Recommendation(s)
Group(s) Aircraft Operation,
Air Traffic Management,
Airport Management
Investigation Type
Type Independent

Description

On 14 April 2011, a Boeing 737-800 being operated by Ryanair on a scheduled passenger flight from Barcelona to Ibiza was involved in a minor collision with a stationary Boeing 767-300 being operated by American Airlines on a scheduled passenger flight from Barcelona to New York JFK whilst both aircraft were in the holding area ahead of full length departures from runway 25L. Neither flight crew was aware that a collision had taken place and the damaged sustained was not found until both flights arrived without further event at their respective destinations - although several passengers on the Ryanair aircraft had reported a collision to their cabin crew. None of the 175 occupants of the 737 or the 239 occupants of the 767 were injured. The damage to the 737 was subsequently assessed as superficial, but that to the 767 as rendering the aircraft unfit to fly without repair.

Investigation

An Investigation was carried out by the Spanish CIAIAC. Flight Data Recorder (FDR) data from both aircraft and ground radar recordings were available to the Investigation. A view of the holding area where the collision occurred taken from the Official Report is shown below:

Holding area of LEBL RWY27L (Source: Final Report)

It was established that both aircraft had been issued with taxi clearances in accordance with applicable procedures and were following them. It was noted that prior to the arrival of the 737, the 767 had stopped at holding point G3. The 737 was cleared to holding point G1 and a following Air France aircraft to holding point G2. Planned and eventual departure was in the same order as their arrival at the holding area. The 737 was being taxied by the aircraft Captain who had relied on the inexperienced First Officer to observe the proximity of her aircraft to the 767 as the taxi behind was begun at a slow speed. The First Officer had then suddenly called ‘stop’ and expressed doubt as to the clearance and the Captain had left her seat to assure herself that sufficient clearance existed. After realising that the 737 may be having difficulty passing behind from R/T exchanges, the 767 crew had moved their aircraft forward a few metres to the furthest point from which the holding point line was visible to the seated pilots. However, the Investigation found that the collision had already taken place approximately three minutes earlier.

Those aspects of aerodrome design covered by the SARPs detailed in ICAO Annex 14 were found to have been followed but to be specified in terms of clearances between aircraft on adjacent parking stands without no applicable reference to the design or use by aircraft of different ICAO size categories of multiple holding point areas such as that where the collision took place. It was noted that these size categories were in any case determined only by aircraft wing span not fuselage length.

It was noted that although the VCR was located only 600 metres from the holding area where the collision had occurred and with a clear view of it, it was impossible for controllers to assess separation distances between aircraft manoeuvring there.

It was also noted that it is not possible for seated pilots in the 737-800 to see the winglets at the tips of their respective wings and that seated 767 pilots have a restricted ground view for 15 metres ahead of the aircraft nose. In the latter respect, the Investigation noted, in the context of the nose of the 767 at impact being approximately 15/17 metres prior to the holding point ground marking, that:

“In this regard, we must bear in mind that when an airplane stops at a holding point, it does so some distance away from the marking at the pilot’s discretion. From the pilot’s point of view, the main concern is not to interfere with aircraft circulating on the runway at any time. A pilot will therefore give priority to this consideration over any potential problems involving tailing aircraft, and will keep the holding point marking well in sight and ahead of the nose of the airplane, barring any instruction to the contrary from ATC. The distance will depend on the field of view that the crew has from the cockpit.”

It was concluded that the stationary positions of the 767 both before and after the collision were not unreasonable given this consideration.

Upon arrival at Ibiza, the 737 Captain had observed superficial damage to the right wingtip but had failed to record this in the Aircraft Technical Log on the grounds that to do so would have led to a substantial delay to the next flight due to the absence of contracted engineering cover at Ibiza. As a result of this, the damage was not properly recorded until the aircraft had completed a further flight back to Barcelona.

The actions of both the cabin crew and Captain of the 737 in respect of passenger reports of a collision were reviewed by the Investigation. It was noted that several passengers had reportedly seen the collision, with one getting up and walking to the rear of the cabin to tell one of the cabin crew of this. This cabin crew had advised the senior cabin crew located at the front of the aircraft and been told by them to advise the flight deck. This communication had been initiated by means of a routine rather than an emergency interphone call and according to the Captain “gave the impression that only one passenger had witnessed the contact, and not several, as she later discovered” and had been prefaced with the words “sorry to bother you, I know I’m not supposed to…” The report had been quickly dismissed by the Captain who had, according to the cabin crew, explained in “aviation terminology” that the two aircraft had come close but had not touched. During the flight, a passenger who had identified himself as an engineer had “expressed concern that they had taken off under those circumstances” and after arriving at Ibiza, several other passengers had also “voiced their preoccupation over the situation”.

The Investigation concluded that the Cause of the collision was that “the crew of the Ryanair B737’s misjudging of the distances as it passed behind the B767, which was stopped at the G3 position of the runway 25L holding point”. It was noted that “assigning position G3 to an aircraft with a long fuselage, such as a B767-300, and the position of said aircraft, relatively far away from the holding point marking, contributed to the incident”. It was also concluded that “the deficiencies in the communications between the cabin and flight crews on the B737 resulted in the collision going unnoticed and in both aircraft continuing with their flights without an assessment of the damage produced”.

Two Safety Recommendations were made as a result of the Investigation:

  • that AENA [the agency responsible for both airports and air navigation in Spain] reassess the taxi limitations applicable to taxiway K and holding points G at both the runway 25L (points G2 and G3) and runway 07R (points G10 and G11) thresholds at the Barcelona Airport. Specifically, AENA is to take into account the effect that the length and position of aircraft situated at the holding points has on taxiing limitations and include these limitations, if any, in ATC procedures. [REC 06/12]

that Ryanair reassess those aspects of its training program involving flight and cabin crew communications and address the deficiencies noted, if any. Special emphasis should be placed on the benefits to safety that stem from the effective transmission of information from the passenger cabin to the flight deck. [REC 07/12]

The Final Report of the Investigation: Report IN-011/2011 was approved for release on 3 May 2012.


Further Reading