The declaration of a ‘fuel mayday’ by a Qantas Airways Boeing 737-800 crew allowed the aircraft to land with the required reserve fuel and prevented a potentially unsafe situation from developing.

The crew made the mayday call before landing in Perth on 18 July 2022 after operating service QF933 from Brisbane which used more fuel originally planned, according to the Australian Transport Safety Bureau (ATSB).


Source: Wikimedia Commons

VH-VZO, which was delivered to Qantas in 2011, is seen here at Sydney Airport

The flightplan called for a southerly – as opposed to direct – track from Brisbane to Perth to avoid headwinds. Near Adelaide the aircraft descended to 28,000ft from 34,000ft to avoid turbulence, says the ATSB’s final report into the incident. The aircraft also flew faster than planned during this part of the flight, resulting in the use of 700-800kg (1,540-1,760lb) of extra fuel.

“At this stage of the flight, the flightcrew identified that they were using more fuel than planned and discussed diverting to Adelaide to load more,” says the ATSB.

“However, as they would be required to hold while they used fuel to reduce the aircraft’s weight to under the maximum landing weight, and they had sufficient fuel to continue to the destination, they decided to continue to Perth.”

Later, the crew also considered landing at Kalgoorlie to get more fuel, but the lenfth of the runway there would also have meant holding to reduce the aircraft’s landing weight. The weather was also poor at Kalgoorlie, contributing to their decision to continue to Perth.

The crew subsequently advised Perth that they had 10min of fuel for holding in traffic but were told that the holding time would be greater than this.

“During the approach to Perth, air traffic control [ATC] advised the crew there were significant delays, over and above the promulgated estimated delay time, for arrivals into Perth. The aircraft did not have enough fuel to hold for the extra time and the flight crew declared a fuel Mayday. The aircraft was then given priority for the approach and landed with their final reserve fuel intact.”

In its safety message, the ATSB underlined that it is critical for crews to advise ATC of a low-fuel situation, and declare a ‘fuel mayday’ if necessary.

“This will ensure that the aircraft receives priority during the approach, preventing an unsafe situation from developing,” says the ATSB.

During the incident flight the aircraft carried 174 passengers and crew.