Rolls-Royce Pearl 10X Engine Nears Certification

Rolls-Royce has completed the tests required for the certification of the Pearl 10X engine, which powers the Dassault Falcon 10X, and is pressing on with integrated powerplant system (IPPS) tests, says Philipp Zeller, Dassault senior vice president at Rolls-Royce.

The Falcon 10X twinjet is Dassault Aviation’s largest business aircraft, and the Pearl 10X is the most powerful engine—at more than 18,000 lb. thrust—Rolls-Royce has ever designed for business aviation. The Falcon 10X, which competes in the high-end business jet segment, started its flight-test campaign in June.

The Pearl 10X completed ground testing for engine certification, and development is ongoing to support certification items at aircraft level. “We deliver an IPPS, with the nacelle, thrust reversers and engine build unit (EBU), which includes ducting and other systems,” Zeller says. The Pearl 10X’s development has relied on 5,000 hours of ground testing, including with the Pearl family’s Advance2 core demonstrator. As of mid-October, the engine has totaled 250 flight hours on both Rolls-Royce’s former Boeing 747 flying testbed and the two Falcon 10Xs in flight tests.

The Pearl 10X’s commonality with other Pearl engines stands at 90%, excluding the EBU and the nacelle. “We injected new technology for higher thrust levels,” Zeller says. Rolls-Royce upgraded the combustor with 3D-printed tiles, enabling higher temperatures and maintaining low emissions. “The tiles help tailor the flow field of cooling air injected into the combustor, thus having a more uniform temperature pattern,” Zeller says. “In the combustor, such a pattern curbs nitrous oxide emissions, [which] form at temperature peak points. Downstream, in the turbine, a more uniform temperature pattern improves the life expectancy of the blades.” In addition, engineers upgraded the accessory gearbox for the power output other systems on the Falcon 10X require.

Rolls-Royce has delivered Pearl 10Xs for Dassault’s four test aircraft, as well as spare engines. Production has started at the engine manufacturer’s factory in Dahlewitz, Germany. Rolls-Royce’s new site near Dassault’s Bordeaux-Merignac final assembly line is supporting the flight tests and aircraft production.

In the Pearl family, the Pearl 15 has amassed 400,000 flight hours on some 200 Bombardier Global 5500/6500 business jets. It is closing in on its 99.9% reliability target, Zeller says. With the Gulfstream G700/G800, the Pearl 700 has accrued 160,000 flight hours on 150 jets in service, he adds.