Rolls-Royce says one of two engine concepts it is developing – the open-rotor UltraFan – could be its route back into to the single-aisle market.
The UK engine maker has revealed more details of two Trent-based “product evolution” designs announced earlier this year: the Advance, which could potentially enter service at the turn of the decade, and the UltraFan, to be ready around 2025.
Simon Carlisle, executive vice-president of future programmes at the Derby-based manufacturer, says the UltraFan “technology could be sized down to a narrowbody application”. He adds: “There would be clear benefits in having that technology, including a geared fan, in a smaller application.”
In February, Rolls-Royce’s Eric Schulz, president of civil large engines, said the company was “preparing to re-enter the mid-market with conviction” as one of its “two big strategies” for the next decade – the other being to protect its 50% share in widebody orders.
Two years ago, Rolls-Royce exited the segment after walking out on Pratt & Whitney and its other partners in the International Aero Engines consortium, which makes the V2500 for the Airbus A320 family.
Rolls-Royce is also hopeful of finding an application for its Advance engine concept, a version of which many believe could be used by Airbus on a re-engined version of the A330, although the planned maturity date for the design – 2020 – could be too late for such a programme.
“We are confident the airframers will develop platforms that we can use this technology on,” says Carlisle. “The Advance will be ready in 2020, so if Airbus decide to develop a product in that timeframe, we will be ready,” he adds.
The Advance’s main design change from the Trent XWB – the engine that powers the Airbus A350 – is that workload is redistributed between the intermediate-pressure and high-pressure compressors and turbines, with bypass ratio increased to more than 11:1. It also adds a carbon-titanium fan system.
The UltraFan uses the same core as Advance but uses an “enhanced” IP turbine to drive the fan through a power gearbox, making the LP turbine redundant. Rolls-Royce says the configuration will be 5% more efficient than the Advance, which in turn will be 20% more efficient than the earliest Trent engines.