The Civil Aviation Authority (CAA) says its made widesweeping changes to safety inspections following a fatal helicopter crash on Fox Glacier that killed seven people.
And chairman Nigel Gould admits CAA's approach was too soft when auditing the company that was operating tourist flights up Fox Glacier before the fatal flight.
On a site-seeing trip up Fox Glacier in 2015 the Fox and Franz-operated Squirrel helicopter crashed, killing all those on board.
An investigation by CAA found multiple safety flaws in the company that operated the helicopter.
"The operator had a poor safety culture with significant shortcomings in its management and its systems," Gould says.
James Patrick Scott, the owner of Fox and Franz Heliservices, was fined $64,000 for safety breaches.
But it's not just Scott's operating procedures that were flawed - the CAA was also found wanting.
An internal review found short-comings in their own work, with inspectors too trusting and not all safety breaches reported.
"With the benefit of hindsight we can say the oversight of JP Scott should have been better," says Gould.
"If it was we would have placed more safety on the operator to lift their safety performance."
Almost all CAA staff overseeing Scott's operations have left the Authority. It's also undergone a major overhaul, increasing the number of inspectors from two to eight and giving inspectors additional training.
The recruitment of CAA inspectors is more rigorous and it's confident the overhaul is working.
"Since the Chancellor shelf crash there has been a major decline in accidents involving helicopters in the scenic tourist flight sector as evidenced by a rolling average graph which shows a 76 percent deduction over a three year period," Gould says.
Just what caused the fatal Fox helicopter crash is expected to be released by the Transport Accident Investigation Commission later this week.