Inaccurate weather reports and confusion about the state of another aircraft's fuel situation led to a Virgin Australia Boeing 737 making an emergency landing at Mildura with dangerously low fuel on board in June.
The revelation has come out in an Australian Transport Safety Bureau preliminary report on the incident, which involved a Virgin 737-800, registered VH-YIR, and a Qantas 737-800, registered VH-VYK, that were operating flights to Adelaide on the morning of 18 June.
YIR was operating a flight from Brisbane with six crew on board and 85 passengers. VYK also had six crew on board and 146 passengers, and was flying from Sydney.
Based on weather forecasts for Adelaide given to the crew of both aircraft prior to departure, each had sufficient reserves and additional fuel on board. However, neither aircraft were required to carry enough fuel for an alternate airport.
While they were enroute to Adelaide, the forecast changed, indicating that fog was expected at their intended times of landing. The crew of VYK received the updated forecast approximately 21 minutes after departure via the aircraft crew address and reporting system. However, the crew of VH-YIR were unaware of the changed forecast until told by air traffic services while near the top of descent.
Both aircraft initially elected to hold at points near Adelaide for a short time, but then diverted to Mildura where they were advised that visibility was fine.
The crew of YIR proceeded to conduct a visual initial approach to assess the weather conditions, and advised air traffic control of their revised fuel status and that there was no alternate. When asked if they wished to declare a fuel emergency, "the crew replied that they would be doing so in the next 10 minutes."
As the aircraft descended through about 10,000ft, the crew became aware of fog and low cloud at the airport. They also reported hearing a Saab 340 conducting a missed approach there and diverting to another airport.
The crew decided to break off the approach and headed to a waypoint southeast of the airport to activate a required navigation performance (RNAV) approach. As they commenced that approach, the crew of VYR also noted that they were commencing approach "and that fuel was an issue."
The crew of YIR assumed that VYR had less fuel on board and so allowed the Qantas aircraft to proceed. The crew of VYR sighted the runway between 100 and 150ft below the published minimum and were able to land, taxi and shutdown with 2100kg of fuel remaining.
Meanwhile, the crew of YIR briefed their cabin crew that they would be conducting an emergency landing. They also noted that due to the fuel state, they would have to land at Mildura regardless of the conditions.
While on the final approach, the first officer made a "Brace, brace, brace" PA announcement, shortly before determining that the aircraft was over the runway. At that point, the pilot in command, who was flying the approach, disconnected the autopilot and was able to land.
The first officer then advised over the PA that the aircraft had landed and emergency procedures were no longer required. The aircraft was able to taxi to a parking area and shut down with only 535kg of fuel remaining.
The ATSB says that its investigation is continuing. It will examine issues around the provision of information to flight crew by operators and air traffic services, the accuracy of aviation weather forecasts and air traffic services policies and procedures that affected the flights.
It adds that it expects to release its final report in June 2014.