Air New Zealand will cancel six international flights and retime others between 7 and 10 December to accommodate urgent maintenance on the Rolls-Royce Trent 1000 engines that power its Boeing 787-9 fleet.
The Star Alliance carrier says that following two recent events, Rolls-Royce has advised that its fleet's Trent 1000 engines “require maintenance sooner than previously indicated”.
“Rolls-Royce does not have any replacement engines available while this maintenance work is undertaken which means some schedule changes are unavoidable,” Air NZ adds.
The schedule changes are primarily affecting services to Houston, Shanghai, Buenos Aires and Perth, and the carrier says it is focused on securing replacement aircraft capacity.
New Zealand’s Transport Accident Investigation Commission says on its website that it is investigating two “engine abnormality” incidents involving Air NZ 787-9s that occurred on 5 and 6 December.
Both incidents involved the engines during climb on takeoff from Auckland, forcing them to turn back. The 5 December incident saw one of the engines shut down, while the second incident saw the crew reduced thrust on the suspect engine before returning to Auckland.
Rolls-Royce says that it regrets the disruption caused to Air NZ, and the two parties are working together to restore full operations of the Trent 1000 engines as soon as possible.
"It’s not uncommon for long-term engine programmes to experience technical issues during their life and we manage them through proactive maintenance," it adds.
The Trent 1000 engine has had a number of technical hitches, which the manufacturer has been working hard to resolve, with a wide range of operators in recent years.
Earlier this year, Rolls-Royce issued a service bulletin calling for increased inspections of the compressor’s rotor section as an interim measure to address possible cracking in the intermediate pressure compressor of the engine while it develops a permanent fix.
That followed an incident in November 2016 when the starboard engine of a Scoot 787-9 failed while enroute to Sydney. The investigation into that incident recommended that Rolls-Royce review the design of the intermediate pressure turbines.