The Transport Accident Investigation Commission (TAIC) wants to hear from anybody who was on board an Air New Zealand flight to Sydney on Sunday and noticed anything unusual after the Airbus A320 issued a mayday but then safely landed in Auckland.
Flight NZ240 was about an hour into its journey from Wellington when it had a problem with Air New Zealand saying the engine was shut down and the plane was then landed safely in Auckland.
TAIC has now opened an inquiry into the incident with a team of two in Auckland to gather evidence for the inquiry.
Chief Investigator of Accidents Naveen Kozhuppakalam said anyone who was on board and noticed anything unusual could talk to the commission in confidence.
"Getting the facts straight is vital, so we're keen to hear as soon as possible from people who were on the aircraft," he said in a statement.
Initial reports suggested there was an engine malfunction, although TAIC could not yet confirm what happened nor why, he said.
"TAIC was informed that the crew turned the aircraft towards Auckland, issued a mayday, then landed safely at Auckland. We understand everyone on board disembarked safely and we have received no reports of injuries," he said.
"Our initial focus is on evidence that could disappear or change - including memories that are fresh in people's minds.
"We're also interested in the individual design, history, performance, maintenance, and equipment of this particular plane and its engines."
For anyone wanting to provide information TAIC's email address is info@taic.org.nz
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