The Government has decided on new helicopters to replace the Air Force's ageing Iroquois choppers.
It expects to pay between $400 million to $550 million for the European-designed NH Industries NH90s and replacements for the Air Force's Sioux training helicopters.
Defence Minister Mark Burton said the exact number the Governmentwould buy was yet to be decided.
However, Mr Burton hinted fewer than the current 14 Iroquois helicopters would be needed. The NH90s can carry 16 fully-equipped troops compared with the Iroquois' seven.
Several Defence Force equipment decisions have been slammed by opposition MPs concerned about cost over-runs and specific purchases. In February, an Audit Office report found there were not enough crews for the Army's 105 new light armed vehicles (LAVs).
Opposition MPs have previously criticised the purchase, saying the Government had bought too many.
The Audit Office report disclosed a funding shortfall for spare parts of $14 million to $19 million and said the annual cost of operating the LAVs over a 25-year life span had increased from $39 million to $48.8 million.
The Government defended the $650 million purchase of the LAVs, insisting that 105 were needed.
Mr Burton said he was confident the helicopter acquisition was "robust".
The aircraft was the best to meet New Zealand's defence and other agency needs, he said.
"It's an all-weather, long-range helicopter. It is an ideal multipurpose helicopter capability for the Defence Force.
"It's got a rear ramp which enables significant cartage of freight, small vehicles like quad bikes and so on."
The lift capability of the new helicopters was roughly double that of the Iroquois "so I guess that gives some sense of the order of magnitude of what's required", Mr Burton said.
He said New Zealand used its utility helicopters on missions in places such as the Solomon Islands or Timor.
They also provided support to police and civil authorities in disaster relief, search and rescue, firefighting and counter drug operations.
"These aircraft will be ideal in a civil emergency situation in terms of their quite significant lift capability - the ability to move people and equipment into troubled areas," he said.
Mr Burton said Australia will also buy the aircraft, ensuring co-operation with a major partner.
The first of the new helicopters will enter service in 2009.
