Rolls-Royce told investors in August that 400 to 500 Trent 1000 engines were affected by issues with components wearing out earlier than expected, according to a conference call transcript.
The Transport Accident Investigation Commission has opened two investigations into Air New Zealand, after two of their flights were forced to turn back this week forcing the airline to accelerate maintenance and cancel flights.
Air New Zealand Ltd on Thursday said it would cancel and delay some worldwide flights over the coming weeks because engines on its Boeing Co 787-9 jets manufactured by Rolls-Royce Holdings PLC required early maintenance.
Air NZ says engine maker Rolls-Royce has advised that some of the Trent 1000 engines in the airline's Boeing 787-9 fleet require maintenance sooner than previously indicated.
On Tuesday morning an Air New Zealand 787 bound for Narita, Japan experience engine abnormality, and returned to Auckland airport after the crew shut down the engine.
Air New Zealand said Rolls-Royce did not have spare engines available while the maintenance work was being undertaken, meaning it would be focused on finding replacement aircraft capacity.
Air New Zealand will be making cancellations and rescheduling some global flights due to the incidents.
An Air New Zealand aircraft made an unscheduled landing last night after circling Tauranga and an area of ocean east of the Coromandel.
The airline's shares were trading 1.6% higher on Thursday, compared with a 0.2% rise for the broader New Zealand market.