The Royal New Zealand Air Force (RNZAF) has been unable to participate in two overseas exercises this year due to lack of aircraft.

New Zealand Defence Minister Wayne Mapp said that the RNZAF could not participate in exercise Maple Leaf in Canada and Green Flag in the US due to delays in upgrades on Hercules C130 and Orion aircraft.

Mapp told the New Zealand Press Association that two of the five C130 aircraft and two out of the six Orion aircraft were undergoing upgrades and were not available for operations.

The Hercules aircraft will be back in service before the end of 2010 and the Orions by the beginning of 2011, according to Mapp.