The Australian Transport Safety Bureau (ATSB) is investigating a Jetstar flight which flew below the permitted level when landing at Queenstown earlier this year.
In a statement yesterday, Jetstar said the carrier was working with the bureau over the incident, which occurred on a morning flight from Auckland to Queenstown on July 16.
"The flight landed safely in clear conditions.
"However, the pilots reported that on approach an incorrect autopilot setting resulted in the aircraft going off its pre-determined track."
It resulted in the plane dropping to 6300ft for a short time when it should have been flying at 7300ft.
"This never put the aircraft in danger and the incident didn't trigger any cockpit alerts.
"The pilots realised the error and corrected it promptly.
"Even if the error had not been corrected, the aircraft would still have landed safely.
"Jetstar takes anything that happens in its cockpits very seriously.
"We are working with the ATSB on its investigation into the incident to identify opportunities to make our operations even safer."
The two pilots - who had a combined total of 23,000 hours' experience and had been flying to and from Queenstown for the past two years without incident - reported the incident to Jetstar and subsequently to Casa, Australia's equivalent of the New Zealand Civil Aviation Authority.
A Jetstar spokesman told the Otago Daily Times yesterday under a treaty between Australia and New Zealand, which covered a "range of things for our flying in New Zealand", Casa was viewed as the air safety regulatory body for Jetstar.
"Obviously, they work closely with the CAA."
The spokesman said a separate investigation by the New Zealand authority was "a matter for them".
CAA corporate communications manager Mike Richards said the authority was aware of the incident, but it would not be investigating.
Earlier this year, a Pacific Blue pilot, who has name suppression, began a lengthy defended hearing in Queenstown over an allegation he operated an aircraft carelessly from Queenstown to Sydney in 2010.
The matter is set to continue in the Queenstown District Court next month.
