Story ID: 446
Rolls-Royce UltraFan Design Frozen 
By: Chris Kjelgaard
Caption: Rolls-Royce’s UltraFan demonstrator project reaches a major milestone. 
Word Count: 223
Rolls-Royce’s UltraFan demonstrator project has successfully passed an internal development review that has allowed the company to freeze the basic design concept of the very-high-bypass, geared-turbofan engine. UltraFan project manager Andy Geer said reaching the milestone "means the concept of the engine is locked and we can move into component design and manufacture.”

The company is planning for first UltraFan production engine availability for commercial service entry in 2025, for potential applications such as Boeing’s New Midsize Aircraft. For a production UltraFan engine, Rolls-Royce is targeting a bypass ratio of 15:1, an overall pressure ratio of 70:1, and a 25 percent fuel burn improvement over the first-generation Trent engines. UltraFan production-engine versions would offer thrust levels scalable from 25,000 pounds to more than 100,000 pounds.

Rolls-Royce is working toward a target date of 2021 to begin ground-tests of an UltraFan development engine, which would integrate all the end products of 12 new technological programs the company is testing in five separate but parallel large-engine development projects. Rolls-Royce has already run the UltraFan demonstrator’s power gearbox (PGB) test article to its maximum design power of 70,000 shp—the highest power output ever achieved by an aerospace gearbox, according to Geer. The company began testing the fourth UltraFan PGB test article in June and expects to begin testing the fifth PGB test article in September.