A strong wind gust blew a Pacific Blue Boeing 737 away from an airbridge as passengers were getting off at Wellington airport in June.
Images of the incident, caught on a security camera and leaked on the website YouTube, show the aircraft being pushed sideways, leaving a big gap - and a three-metre drop to the ground - between it and the passenger walkway.
No one was injured during the incident on 17 June. There were 180 passengers aboard the domestic flight from Auckland.
The Civil Aviation Authority is investigating.
The security images also show ground crew running for safety.
MetService says winds at the time were gusting to 78 kilometres an hour.
Pacific Blue says it has since made changes to ground procedures requiring chocks to be put at the rear wheels and for the parking brake to be applied when wind gusts are strong.