Minister for Defense Materiel Jason Clare said the helicopters will help maintain and develop the skills of junior naval helicopter aircrew. The contract includes support and maintenance of the aircraft, he said.
"This is one way the navy is making sure that pilots and aircrew are ready for the new Romeo combat helicopters, which will start arriving in 2014," Clare said.
"Junior aircrew initially train in Squirrel helicopters. They will then move on to the Bell 429 to improve and maintain their skills.
"This gives young naval pilots and aircrew the chance to hone their skills before they start flying the new combat helicopters, the MH-60R Seahawks or the new MRH-90 helicopters."
The lease of the helicopters is necessary to assist in the skills development of naval aircrew following the government's cancellation of the failed Seasprite project.
The new helicopters will operate for four years -- from 2012 -- and are expected to fly around 1,500 hours per year.