A public acknowledgement of failure by the country's aviation watchdog has astonished some in the sector.
The Civil Aviation Authority's admission follows last week's sentencing of company directors over a helicopter crash on Fox Glacier in 2015 which killed all seven people on board.
The Authority's chair, Nigel Gould, says the authority undertook an internal review to identify any shortcomings in its processes.
Aviation commentator Irene King says she is flabbergasted that Mr Gould spoke to media before the final accident report is out. It is expected later this week. Irene King talks to Corin Dann.