FACTUAL INFORMATION

On 2 February 2006 at approximately 1308 Eastern Daylight-saving Time¹, a US registered Boeing Company 747-422 (747) aircraft was taxiing for departure at Melbourne Airport, Vic. At the same time, a Boeing Company 767-338ER (767) aircraft was stationary on taxiway Echo and waiting in line to depart from runway 16. The left wing tip of the 747 collided with the right horizontal stabiliser of the 767 as the 747 passed behind the 767. Both aircraft were on scheduled passenger services from Melbourne to Sydney, NSW. 

The 747 sustained substantial damage to the leading edge of the left wing tip. The left wing tip fairing sustained chord-wise damage except for a small section near the trailing edge of the wing. The left navigation and strobe light coverings were destroyed. The left winglet remained undamaged (Figure 1).

Figure 1:     Damaged left wingtip of the 747

The 767 sustained significant damage to the right horizontal stabiliser. A substantial section outboard of the elevator was destroyed (Figure 2).

Figure 2:     The damaged right horizontal stabiliser of the 767

There were two pilots in the cockpit of the 747 at the time of the occurrence. The pilot in command was steering the aircraft and reported that he could see the left wingtip of the aircraft. The 767 was stationary on taxiway Echo between taxiway Alpha and runway 16. It was the third aircraft in a queue for departure from runway 16 from taxiway Echo. The right horizontal stabiliser of the 767 was protruding approximately 8.75 m into taxiway Alpha and 1.7 m west of the centreline of taxiway Alpha (Appendix A).

The flight crew of the 767 disembarked the aircraft’s 165 passengers and crew via airstairs while the aircraft remained on the taxiway. The passengers and crew of the 747 remained on board their aircraft while the aircraft was towed back to a parking position on the international apron. There were no reported injuries to any of the passengers or crew on board either aircraft.

The flight crew of the 747 stated they could clearly see the tail section of the 767 as they moved along taxiway Alpha. As the 747 approached the intersection of taxiways Alpha and Echo, the pilot in command turned the aircraft right, and into the intersection to manoeuvre around the 767. Both pilots of the 747 reported that the taxiing speed of the 747 was no more than 10 kts, which was slower than usual for straight taxiway sections.

There was a large concrete area at the intersection of taxiways Alpha, Echo and Foxtrot (Appendix A). The intersection provided considerable room for the 747 to manoeuvre to the south and east of the 767. However, the north-eastern side of the concrete area narrowed, reducing the space available for the 747 to manoeuvre past the 767. The pilot in command reported that, as he taxied behind the 767, he thought the left wingtip of the 747 was clear of the tail section of the 767, and decided it was safe to proceed past the 767.

The taxiway dimensions and markings at Melbourne Airport complied with international standards and were suitable for use by the aircraft types involved in the occurrence.

The Australian Manual of Air Traffic Services (MATS) promulgated the objectives of air traffic control, including the prevention of collisions between aircraft, and to expedite and maintain an orderly flow of traffic. Control of aircraft taxiing on the manoeuvring area of Melbourne Airport is managed by a surface movement controller (SMC) operating from the control tower. According to the MATS, separation of aircraft on the manoeuvring area is a joint responsibility between a pilot in command and a controller. Also, a number of pilot reference documents, including the Australian Aeronautical Information Publication² and the USFederal Aviation Administration Aeronautical Information Manual³, advised that pilots are responsible for collision avoidance while taxiing.

At Melbourne Airport, pilots were required to obtain a clearance to taxi from the SMC. The pilots of the 747 received a clearance to taxi, which included a taxi route from the international apron to the holding point on taxiway Bravo, for a departure from runway 16, via taxiways Uniform then Alpha. It did not include approval to deviate off taxiway Alpha and into taxiway Echo to pass behind the 767. The pilots of the 747 acknowledged receipt of that clearance and read it back to the SMC. They were not advised about the location or intentions of the 767, or provided with instructions by the SMC to avoid the 767.

The SMC at Melbourne Airport was seated towards the left side of the console in the control tower. There were structural posts in the windows around the tower that obscured the view of parts of the airport from the SMC. Examination of the SMC position revealed that the intersection of taxiways Alpha, Echo and Foxtrot could periodically become obscured from the view of the SMC, depending on how the controller was seated in the SMC position (Figure 3). Further, the angle from the SMC position to the intersection of the taxiways made any visual assessment of the position of an aircraft on taxiway Echo, relative to taxiway Alpha, difficult to judge. The SMC reported that he could see both the 767 on taxiway Echo, and the 747 taxiing along taxiway Alpha although he could not determine the extent to which the 767 was protruding into taxiway Alpha.

Figure 3: View from SMC position in the control tower looking north-east

The 747 flight crew reported that they were appropriately rested and were fit for duty at the time of the occurrence. They were scheduled to remain overnight in Sydney before continuing on to Los Angeles. The pilots were on schedule and reported being under no pressure to continue to taxi, rather than wait for the 767 to taxi clear of taxiway Alpha.

The weather was reported as fine and clear and was not considered to be a factor that contributed to the accident⁴.

1. The 24 hour clock is used in this report to describe the local time of day, Eastern Daylight-saving Time, as particular events occurred. Eastern Daylight-saving Time was Coordinated Universal Time (UTC) +11 hours.
2. ENR (En Route) 1.4 section 2.2.1 (effective 24 November 2005), stated that ‘the pilot must maintain separation while complying with clearances and instructions’.
3. Federal Aviation Administration Aeronautical Information Manual, Official Guide to Basic Flight Information and ATC Procedures, Chapter 4, Air Traffic Control, section 4-3-18 (effective 16 February 2006), stated that ‘Although an ATC clearance is issued for taxiing purposes…it is the responsibility of the pilot to avoid collision with other aircraft.’
4. Although the photograph shown at Figure 3 was taken some time after the accident, it is indicative of the reported weather conditions that prevailed at the time of the accident.