Rolls-Royce unveils upgraded Trent engines targeting improved fuel efficiency

Rolls-Royce will offer the new XWB-84 as an option for operators of new A350-900s. In addition to flight tests, engineers have conducted endurance testing at Rolls-Royce's ground test facility in Derby, UK, where it ran a 2,800-hour hot-cycle test.

The fuel efficiency improvement is part of a £1 billion ($1.3 billion) investment in enhancements to the Trent family since its introduction in the 1990s. Rolls-Royce expects these changes to increase turbofan durability.

Upgrades include a disc alloy applicable to both the XWB-84 and Trent XWB-97 engines. Burr explained that the RR173 super alloy provides an improved safety margin allowing engines to run at least 50 kelvins hotter or extend service life.

With regard to the XWB-97 engine, Rolls-Royce aims to double permitted time on wing in challenging environments such as those found in the Middle East. Enhancements include increased temperature margins and improved turbine case cooling.

A new coating resistant to calcia-magnesia-alumino silicates has been added for HPT seal segments. This upgrade will be available for HPT blades later this year with further modifications scheduled for rollout by 2028.

“The interface between the engine blade and case has been running hotter than we’d modeled,” Burr noted. Extensive rig testing at Derby’s Testbed 80 facility included sandblasting engines with desert-like sand compositions verified by PhD-level geologists.

In response to reliability issues with Trent 1000 turbofans used on Boeing’s 787 widebody airliner, Rolls-Royce introduced a new HPT blade already employed with Trent 7000 engines since September 2022. “We lost market share because it simply wasn’t durable enough,” admitted Burr.

Flight testing for this new Trent 1000 blade is scheduled for August using a 747 testbed aircraft. Following initial certification by EASA, deliveries are expected early in 2025.

Applied improvements from Trent 7000 designs have reduced blade metal temperatures significantly and are planned as retrofits across all Trent 1000 models.

Commercially, Rolls-Royce forecasts a return to pre-2019 market conditions this year with increased engine deliveries driving demand for product support. Recent orders include purchases from Turkish Airlines, Delta Air Lines, Japan Airlines (Trent XWB), and Vietjet (Trent 7000). New operators like IndiGo, EVA Air, and Korean Air join existing customers amid rising express delivery demand bolstering growth in air freight sectors.