The plane departed from Franz Josef at about 9am today and was en route to Rangiora.
RCCNZ was co-ordinating the search for the missing aircraft.
They notified RCCNZ that its assistance may be required at 11am this morning after the aircraft was reported overdue.
A spokesperson from the RCCNZ said earlier today that weather had hampered efforts to get rescue assets to the area to undertake a search.
"Aoraki/Mt Cook Alpine Cliff Rescue is preparing to join the search, and will liaise with a local helicopter operator should conditions improve.
"An RNZAF NH90 helicopter is repositioning to the South Island to assist."