A failure to update flight crews about deteriorating weather conditions at Adelaide resulted in two Boeing 737 aircraft landing at Mildura in foggy conditions with fuel below the fixed reserve.

In its final report about the 18 June 2013 incident, the Australian Transport Safety Board (ATSB) identifies several factors as contributing to the incident, but highlights two safety issues.

The first is that automatic broadcast services lack the capacity to recognise and disseminate special weather reports to pilots. Second, most Australian non-major airports, such as Mildura, offer current weather information via very high frequency radio, which has range limitations.

“Where this service is available, air traffic services will generally not alert pilots to significant deteriorations in current weather conditions at such airports, increasing the risk of flight crew not being aware of the changes at an appropriate time to support their decision making,” says ATSB.

The aircraft involved were a Qantas Airways 737-800 (VH-YIR) operating flight 735 from Sydney, and a Virgin Australia 737-800 (VH-VYK) operating Velocity flight 1384 from Brisbane, both on morning flights to Adelaide. The Qantas jet had six crew and 146 passengers aboard; the Virgin jet six crew and 87 passengers.

“On nearing Adelaide, the forecast improvement in weather conditions had not occurred and as a result, both aircraft commenced a diversion to Mildura, Victoria,” says the ATSB.

“Upon arrival at Mildura, the actual weather conditions were significantly different to those forecast, in particular with visibility reduced in fog. The flight crew of Qantas 735 conducted an instrument approach and landed below minima. The flight crew of Velocity 1384 also conducted an instrument approach and landed below minima in fog and with fuel below the fixed reserve.”

As a result of the incident, several parties are improving their procedures. Air traffic control provider Airservices Australia will work with the Bureau of Meteorology to explore ways to provide more timely information about deteriorating weather. The Bureau of Meteorology has also upgraded systems and equipment used for forecasting.

The ATSB is not completely satisfied with Airservices’ response to the matter: “The ATSB is concerned that Airservices, as the agency that provides flight information service in Australia, has not taken responsibility for the resolution of this safety issue. In addition, the indefinite nature of the proposed activity does not provide a high degree of confidence that the safety issue will be adequately addressed.”

Virgin Australia has also enhanced its flight planning communication infrastructure.

“Pilots are reminded of their responsibility for collecting all relevant information to support in-flight decision making,” says ATSB. “This includes weather and operational information for the destination, which should be considered prior to a decision point or point of no return.”

Source: Cirium Dashboard