EBACE Convention News

Rolls-Royce Pearl 700 Engine on Home Stretch

 - May 23, 2022, 1:13 AM
Rolls-Royce is putting the finishing touches on the Pearl engine for the Gulfstream G700. (Photo: David McIntosh/AIN)

Rolls-Royce (Booth X93) is wrapping up testing on its Pearl 700 engine for the ultra-long-range Gulfstream G700 and shifting to “production mode,” said Colm Golden, Rolls-Royce's senior v-p for the Pearl 700 program. The company has delivered several production engine shipsets to the OEM sincde handing over the first ones late last year and already has issued two-thirds of the necessary certification reports.  

Meanwhile, Golden reports that the test campaign on the Pearl 10X for Dassault’s large-cabin flagship is also proceeding well. Both the Pearl 700 and 10X are rated to produce more than 18,000 pounds of thrust and deliver significant increases in efficiency.

Compared to the Rolls-Royce BR725 that powers the Gulfstream G650 series, the Pearl 700 delivers an 8 percent increase in takeoff thrust, a 12 percent better thrust-to-weight ratio, and a 5 percent higher efficiency. Rolls-Royce has achieved these gains by mating advanced materials and manufacturing techniques, including the use of 3D-printed combustor tiles.  

Using 3D printing on the tiles allows Rolls-Royce engineers to optimize their shape in ways that traditional manufacturing cannot, Golden said. “You can have more complex shapes and enable the most efficient combustion process.” He added that the technique is being used to fashion other engine parts as well such as brackets and levers, generally to save weight. 

Metal injection molding is another relatively new technology being applied to the engine’s manufacture that enables the production of complex shapes in a single step. The process creates and shapes parts via injection molding using powdered metal mixed with a binder material. Once molded, the binder material is removed from the part. Friction stir welding also is being used in the engine’s manufacturing. Like most new jet engines, the Pearls use a forged blisk fan to reduce weight and drag.  

But Golden stressed that the Pearl’s highly-efficient core is really its secret sauce and that by optimizing it and the parts around it, Rolls-Royce has developed “the most efficient core in business aviation. Our technology provides new tools to our designers that can really take us to the next level, enabling smaller cores that provide better performance. With bigger aircraft, cores really need to get smaller,” Golden said. The “Advance2” core on the Pearl features a 10-stage, high-pressure compressor with six titanium blisks and a 24:1 pressure ratio.