The Phuket crash follows closely on the belated decision to hold an Australian inquiry into a bad weather incident involving a Jetstar flight that had a much happier ending.

The Australian Transport Safety Bureau has launched a level three inquiry into the incident on 21 July when a 177 seat Jetstar A320 arriving from Christchurch came within 20 feet of the ground at Melbourne Airport while making two missed approaches in fog.

A level three inquiry is one “where investigation is likely to significantly mitigate future accidents.”

Until that investigation was launched Jetstar had been allowed to conduct an internal inquiry into the incident.

But it took Jetstar weeks to work out that something was amiss in the conduct of what should have been a routine set of missed approaches before the crew decided to divert to nearby Avalon Airport, which was fog free.

The airline then issued confusing statements as to what had happened, and went on to claim there had been a failure in the functioning of the automatic go-around system in the Airbus.

Suddenly the Minister of Transport, Mark Vaile, was asking questions, his regulator the Civil Aviation Safety Authority, stopped saying it was all a minor matter best left to the carrier, and a dossier full of evidence about what really happened on board the Jetstar flight lobbed on the front desk of the independent investigator, the Australian Transport Safety Bureau.

Whatever might have failed on the Jetstar flight, whether human or mechanical, there was a failure in process intended to ensure the prompt and public investigation of flight safety incidents involving a mainline Australian carrier.

Nothing adverse is known or suggested about Jetstar’s determination to get to the bottom of the incident. But an internal inquiry was inappropriate.

A claimed failure of a major system in a widely used airliner should trigger an immediate independent inquiry like the one now underway, but two months late. The ATSB is required to produce an interim factual report into the Jetstar incident no later than 5 October. After that comes the full report, which may take months to finalise.