Rolls-Royce is developing two new Trent-based engines – ready for service in 2020 and 2025 – which it says will deliver fuel efficiencies of up to 10% over the Trent XWB engine for the Airbus A350.

The later of the two engines could use open-rotor technology for the first time.

Revealing the projects at a briefing in Derby today, the UK engine maker’s executive vice-president of strategy and future technology Simon Carlisle said it has “begun sharing the story” with airframers and airlines, but does not have any commitments yet for applications. However, the technology “builds on” the architecture of the XWB.

The first engine – which has the development name Advance – will alter the core of the three-shaft Trent with a larger high-pressure compressor and smaller intermediate pressure compressor. It will also adopt carbon-titanium fan blades and a composite casing that Rolls-Royce says will reduce aircraft weight by up to 680kg (1,500lb). The engine will have a bypass ratio of 11:1.

The second product to be developed – using geared technology and dubbed UltraFan – will increase the bypass ratio to 15:1. Introducing a geared-fan to the engine is an “option for later”, says Carlisle.

Rolls-Royce plans to test the Advance engine – by replacing the core of a Trent XWB – next year and fly a demonstrator of its UltraFan by the end of the decade. “Our philosophy is that at any time we have a fundamental redesign of architecture we will fly it,” he says.

Product names for the engines will be announced “at a later stage”.

Source: Cirium Dashboard