Air New Zealand has been forced to cancel a number of flights over the holiday period due to 'Rolls-Royce maintenance requirements”.

In a statement released today, Air New Zealand says it is making some changes to its international schedule over summer 'as a result of ongoing global issues impacting some Rolls-Royce engines on its Boeing 787-9 aircraft”.

Rolls-Royce requires operators of its Trent 1000 TEN model engines to carry out more frequent maintenance due to an issue with the engine's high-pressure turbine blades.

Rolls-Royce does not have any replacement engines available while maintenance work is undertaken and has advised Air New Zealand there's significant wait for repair services.

Air New Zealand has 10 Trent 1000 TEN engines fitted to its 787-9 fleet and has been working to minimise disruption but schedule changes are now unavoidable.

Further changes may also be required as the airline progresses the engine checks.

Air New Zealand Senior Fleet Manager 787 Captain Dave Wilson says the airline has been performing regular precautionary checks on its TEN engines since April and has been doing all it can to fast-track required maintenance from Rolls-Royce.

'Based on the maintenance needs of our engines, we expect some will need to be inspected in December and January and then serviced by Rolls-Royce offshore and unfortunately Rolls-Royce has no capacity to alleviate this pressure.

'We have 14 787-9 Dreamliner aircraft in our fleet and four spare engines to power these. However, all these spare engines are with Rolls-Royce offshore either undergoing service or waiting for a service slot.”

Air New Zealand Senior Manager Customer Care and Communications Doug Grant says while the airline never expected to still be facing issues with its Rolls-Royce engines, it's well placed to navigate these with the least impact to customers.

'Going into the holiday season we're acutely aware how important travel is to our customers, and our schedule changes are designed to keep cancellations to a minimum.

"Unfortunately, around 14,000 customers will be impacted by cancellations and we thank them in advance for their understanding."

The most substantive of changes announced today is the suspension of its twice-weekly seasonal Christchurch-Perth service, resulting in the cancellation of 62 flights.

The airline will also cancel its second daily Auckland-Perth service from December 10, 2019, until January 5, 2020.

The airline will continue to operate its 11.10am Auckland-Perth and 6.50pm Perth-Auckland services as scheduled.

Outside the Perth route, a limited number of international cancellations will also take place from December 10 - January 2 as follows (all dates given in local time):

The airline will start processing changes to customers' bookings this week and then directly contact customers affected by these changes with new travel information.

Customers booked via a travel agent (including online travel agents) will be contacted by their booking agent.

The latest information on any changes will also be published on the Travel Alerts section of the Air New Zealand website and customers are encouraged to check this, before calling the airline's contact centre. Customers are also welcome to directly message the airline through its social media channels.

Air New Zealand has been managing issues with the Rolls-Royce Trent 1000 engines since December 2017, when it first secured lease aircraft capacity to help maintain its timetable. The airline still has one widebody aircraft on lease from EVA Air in its fleet.

There is no impact to the airline's 22 Trent 1000 Package C model engines as a result of this HPT blade issue.