Rusting Navy choppers fight to stay in the air

A SeaSprite parked up in a paddock after a 'precautionary' emergency landing in 2008. Photo / Brett Phibbs

The navy's five helicopters, worth $350 million, are struggling to stay in the air as the Defence Force battles corrosion and a lack of staff to maintain the "orphan" fleet.

A Ministry of Defence report says three Kaman SH-2G (NZ) Seasprite anti-submarine helicopters have to be flying at any one time but last October only one could get in the air and earlier this year just two serviceable Seasprites were available, the Sunday Star-Times reported.

New Zealand bought the helicopters in a "steal" deal in 1999. The airframes had been stored in the Arizona desert before being fitting out for New Zealand.

However, soon afterwards the US Navy ditched Seasprites and scrapped its flight simulator, leaving New Zealand - which now has the only particular model flying - struggling to train pilots and parts are not easily available.

Defence Minister Wayne Mapp labelled the Seasprites "an orphan fleet" when in opposition, but last week said they were safe and very capable.

"I am confident, based on the assurances I have received, that safety is not the issue here."

The ministry report says because the need to keep the helicopters flying, the military is constantly deferring operational level maintenance - creating a "bow-wave of deferred maintenance".

Engineers were finding corrosion or vibration damage and while cumulative deferral might be considered safe, the report said it was reasonable to assume the "damage will worsen the longer it is left".

Damage was "being found in areas where such corrosion or damage has not been seen before", the report said.

The corrosion was probably caused by a lack of awareness by staff, and training deficiencies, the air force said.

It was hard to get staff to go with the helicopters when posted at sea for six to eight months.

"This unwillingness to serve at sea results in No6 Squadron having difficulty retaining people with deep knowledge of the Seasprites," the report said.

Air Vice-Marshall Peter Stockwell said the Seasprites were ideal for their naval role and "absolutely safe to fly".

Deferring maintenance was tightly controlled, and airworthiness was reviewed constantly. He said deferment was often necessary when the aircraft were on frigates at sea. "It is very carefully managed," he said.

- NZPA

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