02/07/2008 21:30. Rolls-Royce expects to freeze the design of the baseline Trent XWB turbofan by the end of July and sees no significant implications from Airbus's recent decision to increase operating weights for all three members of the A350 XWB .

"We put a big fan on [the Trent XWB] deliberately because if the weight goes up, that's what constrains the noise," says Colin Smith, R-R's director of engineering and technology.

He adds that Airbus is "actually freezing the baseline design now and I don't think we quite know where the aircraft's going to be. There's a long way to go on the programme, but broadly we have a common bill of material throughout the power range."

The first three-shaft Trent XWB is scheduled to undergo bench testing in early 2010 and the engine is due to be certificated by the... // Flight International