As if a fake ground engineer and dodgy electrical repairs weren’t enough to rattle Qantas regulars, the Australian Transport Safety Bureau has dropped an incident report which reminds the airline of the need to make sure its jets have enough fuel to reach Perth.

The report says that on 16 September last year the crew of a Qantas A330 approaching Perth from Singapore for a midnight landing made two missed approaches in fog and then called “Mayday”, the international distress signal, as they made a risky autoland approach.

This is the first reference industry sources can find to a Mayday call in an incident report involving a Qantas jet, although some thought there had been one involving multiple engine troubles on a 747 that made a hasty return to Sydney Airport in the 1970s.

The successful third attempt at landing at Perth was made when the Airbus was very low on fuel following the previous two attempts, and the only other course of action would have been to attempt a ditching at sea.

While Qantas international pilots are trained in autoland procedures at some overseas airports, they are not approved for anything other than emergency use at Australian airports because none have ground based navigational aids that are certified as reliably generating signals of sufficient accuracy for such ultra low visibility landings.

The flight had departed from Singapore without enough fuel to make a last minute diversion from Perth to the nearest suitable big jet airport which was Learmonth, 1110 kilometres to the north.

As the uber low key language in the ATSB report makes clear, this was in accordance with long standing Qantas fuel policy in relation to Perth.

But while Perth flights have long been a ‘special case’ for jet airlines in general because of its remoteness from suitable bad weather alternatives, there is a key issue at stake.

Qantas captains are under constant pressure to carry not a litre more in fuel than company operating procedures deem appropriate for each flight.

This tight fuel policy impinges on the traditional authority of captains to rely on their experience and judgement in calculating fuel appropriate to the variable conditions under which a flight operates.

Qantas has now implemented an interim fuel management plan for Perth which in lay terms says more fuel will be loaded whenever there is more than a hint that fog may form over its runways within an interval of some hours of scheduled arrival.

Which is timely, as it yesterday announced a $50 million upgrade to the Perth terminal, which its jets now have more certainty of reaching than was the case one dark and suddenly foggy night last September.