The Defence Force is looking to upgrade its Orions so they can detect submarines.
If approved, the six aircraft will be installed with modern sonar equipment which will be able to identify underwater objects.
The Ministry of Defence asked in 2010 for an upgrade to be investigated after existing equipment became obsolete.
Ministry spokesperson John Campbell says the Orion is a surveillance aircraft and anti-submarine warfare has always been a part of its roles.
Captain Campbell says the Defence Force has to complete a report about the necessary upgrades for the Government to consider.
The executive director at Victoria University's Centre for Strategic Studies says in the past few years there has been an acceleration in the spread of submarines in the wider Asia-Pacific.
Professor Robert Ayson says it is a big issue and the question is whether New Zealand wants the ability to contribute to the surveillance of submarines with its allies.