ATSB probes Qantas (767) and Jetstar (A330) serious incidents

Two recent incidents officially rated as serious involving Jetstar and Qantas flights are under investigation by the ATSB.

The Jetstar incident, on October 28, may have involved an iced up pitot or external speed measuring device on an A330 which was flying from Tokyo to the Gold Coast.

The flight experienced an involuntarily autopilot disconnection and indications of erratic airspeed data. It continued without further incident to the Gold Coast.

The ATSB inquiry will try to establish if it was related to the icing up of a pitot tube, an external airspeed measuring device, or was a manifestation of the malfunction of an inertial data device blamed for a loss of control by a Qantas A330 near Learmonth in WA last October, which involved many injuries to passengers and crew and an emergency landing at the military base.

That Qantas accident is under separate investigation by the ATSB.

An Air France Airbus A330 crashed with the loss of all 228 people on board into the mid Atlantic on June 1 after sending automated messages that indicated that at least one of its pitot tubes had become ice up before it entered a zone of severe turbulence.

The Air France investigation is continuing and has not determined the cause of the accident, but the type of pitot tubes fitted to it, and made by Thales were about to be replaced by the airline after its own tests found them to be inadequate. Thales pitots have subsequently been banned from use on Airbus A330s and A340s under a world wide compulsory airworthiness directive.

However the Qantas and Jetstar A330s have never used Thales pitots but rely on a Goodrich design which has so far been reported as trouble free.

The other serious incident under ATSB scrutiny occurred to a Qantas 767-300 flight from Melbourne to Sydney on October 26. The safety investigator says that:

Passing 700 ft on approach into Sydney, the crew commenced a missed approach due to the aircraft being incorrectly configured for landing. During the commencement of the missed approach the “too low gear” GPWS warning activated.

Just how or why a passenger flight found itself making a go-around in these circumstances rather than in relation to weather or visibility issues which are the cause of most aborted landings is mystifying.