A private jet company boss has voiced concerns about what could happen if there's not reform at the Civil Aviation Authority - and he's taken these worries to the Government.

NZ Jet owner John Ambler has heard concerns from former and current CAA staff about the organisation's culture. 

He says it includes an erosion of expertise, and operators fearing they'd be punished for raising concerns. 

"We are losing experienced people within the civil aviation department at a great rate...it's alarming. And obviously, if these people within the unit aren't able to speak up for fear of reparations - what sort of system have we got?"

Meanwhile, Air Chathams CEO Duane Emeny says there was need for change three years ago, and that Minister Simeon Brown acted quickly. 

"He got quite a few new board members in, the whole leadership team in the CAA changed and, actually, we can sit here today and say, quite confidently, that we are seeing some of the good and positive outcomes of those changes."

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