Rolls-Royce will address the maintenance cost impact of its decision to incorporate a new, scaled-up core in the Airbus A350-1000's Trent XWB - which eliminates commonality with -800/900's engine - through its Total Care support programme.
The UK engine maker had previously planned to base the A350-1000's 93,000lb thrust (414kN) Trent XWB on the 84,000lb thrust version that powers the -900, with some material and fan module changes.
However, to meet Airbus's requirement for 4,000lb more thrust, R-R (chalet B89) is incorporating a larger core which eliminates much of the commonality, although it will retain the lower-thrust engine's 300cm (118in) diameter fan.
"The systems, interfaces and nacelle external lines are going to be common, as well as a lot of the accessories. So for the airline, the interface with the aircraft is going to look like the same Trent XWB," said R-R civil aerospace president Mark King.
"There is a lot of commonality in the supply chain and the systems and the bits that the airlines deal with on a day-to-day basis, for example the training.
"It's only the off-wing stuff that is going to have the impact, where there is limited part number commonality in the core, and we can take care of that under [the] Total Care [support package] as part of the solution."
King said that the decision to go with a derivative rather than all-new design means the programme is lower risk. "Even the new core is not a redesign, it is a scale."
The A350-1000's new Trent XWB will not be interchangeable with the -800/900's.
R-R said that it was the design intent for the original A350-1000 engine to be interchangeable with the lower-thrust version.
King expects that Airbus (chalet S3 418) will test the revised Trent XWB for the A350-1000 on its A380 flying test bed, ahead of the new twinjet's flight trials. The -1000, which is the largest A350 variant, is due to enter service in 2017.