Sequence of events
At 1940 eastern standard time (EST), on 4 October 2004, the
Boeing Company 737-300 aircraft, registered ZK-FDM, became bogged
(Figure 1) at Melbourne Airport. The aircraft was being taxied to
runway 27 for a scheduled international passenger service to
Hamilton, New Zealand.
Figure 1: Left main landing gear tyres after
penetrating the blast-protection surface adjacent to taxiway
Papa.
The flight crew commenced taxiing the aircraft to runway 27 from
bay 'Delta 4' at the international terminal. Taxiing to
Papa1 via Tango was
not available because of the stage A2a works in progress on the
northern apron (depicted at Attachment 1), and the surface movement
controller (SMC) instructed the crew to taxi the aircraft via
Sierra and Echo to the runway 27 holding point on Papa. As the
aircraft approached Sierra the crew requested confirmation of the
taxiing instructions, and the SMC repeated those previously given.
The SMC then told the crew to contact the aerodrome controller
(ADC) on frequency 120.5 MHz.
The flight crew subsequently reported that while taxiing east
along Echo, their attention had been drawn to the lighting
associated with the apron works near the intersection of Tango and
Papa. There was a holding bay located north of Echo, and the first
lead-in light to the holding bay was about 40 m west of the first
lead-in light to Papa. As the aircraft approached the lead-in
lights to the holding bay, the pilot in command stopped the
aircraft. The copilot asked the ADC "is it hard left Papa
here?"
The ADC was located in the aerodrome control tower, which was
about 1,450 m to the west-southwest of the aircraft's position.
From the ADC's vantage point, and in the night conditions, the
aircraft would have appeared to have been at the lead-in to Papa,
and the ADC confirmed to the crew that it was Papa.
The pilot in command, in response to the advice from the ADC,
turned the aircraft left and began to enter the holding bay,
thinking it was taxiway Papa. It then became obvious to the crew
that they were not on Papa, and the pilot in command turned the
aircraft to the right to regain taxiway Echo and the lead-in to
Papa. He subsequently reported that another aircraft taxiing on
Quebec for runway 27 had its lights 'very brightly shining', and
that he misidentified the double lines on the taxiway shoulder as
being the taxiway centreline. As a result, the pilot in command
inadvertently steered the aircraft onto the blast-protection
surface adjacent to the taxiway shoulder pavement. The left main
landing gear tyres of the aircraft penetrated the blast-protection
surface, and the aircraft became bogged.
The aircraft could not be moved from its bogged position, and
the 104 aircraft occupants, which comprised two technical crew,
three cabin crew and 99 passengers, were disembarked and taken back
to the international terminal.
The aerodrome operator reported that all airside signs, markings
and lights complied with ICAO standards and CASA regulations, and
that they were serviceable and operating normally at the time of
the occurrence. The circumstances of the occurrence did not suggest
that there were any deficiencies in the aerodrome airside signs,
markings and lighting systems.
The aircraft weight and balance data for the planned flight
revealed that its taxi weight was 54,434 kg, and the centre of
gravity was at 20.4 percent mean aerodynamic chord. Under those
conditions, about 90 percent (49,500 kg) of the aircraft's total
landing gear pavement load was exerted by both the main landing
gears, that is, each main landing gear pavement load was about
24,750 kg. The left main landing gear pavement load was of
sufficient magnitude to result in the left main landing gear tyres
penetrating the blast protection surface.
The aircraft was recovered from its bogged position on the
following day, and subjected to a heavy landing engineering
inspection. The inspection revealed no damage resulted from the
incident, and the aircraft was returned to service.
