Aviation bosses have ordered the biggest grounding of aircraft in the country's history amid fears a helicopter fault may be behind the deaths of two men.

The Civil Aviation Authority yesterday grounded 80 helicopters two days after Stephen Combe and James Gardner died in a crash in Queenstown.

It is believed a rotor blade from the Robinson R44 helicopter they were flying may have failed. Aircraft parts have been sent to the US for analysis. The indefinite grounding will dent parts of the tourism and agriculture industries where the choppers are commonly used.

CAA spokesman Mike Richards said owners of the helicopters had been ordered to get their aircraft back to home base and told not to fly. It was not clear how long they would be grounded for.


"There are quite severe penalties if anyone is caught flying once the directive is handed out," said Richards. "We don't do things like this lightly but you can't put a price on safety. It's better that our reputation and skies are safe."

The CAA will contact owners about the directive. It keeps a register of all aircraft in the country.

A team of accident and CAA investigators yesterday completed the recovery of the wreckage from Thursday's fatal crash.

It will be taken to the Transport Accident Investigation Commission's Wellington technical facility for checks.

Graeme Harris, director of Civil Aviation, said there were similarities to an earlier R44 incident when a main rotor blade failed.

On January 23, a pilot in an agricultural helicopter experienced severe vibration but was able to land safely. The blade from that incident was being sent to the manufacturer and the US Federal Aviation Administration for analysis.

Combe, 42, and Gardner, 18, worked for Queenstown's Over the Top helicopters.