It is rare for an engineer to work on a jet engine program from preliminary design to entry into service. It’s few and far between who can say they worked two widebody engine programs from preliminary design to entry into service back to back. That’s what Steve Ross, principal engineer for the GE9X Systems Engineering team, hopes to achieve.
Ross worked on the GEnx engine, seeing that program from beginning of Tollgate 0 to Tollgate 9, when the business confirms the readiness levels of the Supply Chain and Services and greenlights the engine to enter service. Then he joined the GE9X program in 2010 as the Manager of the Mechanical Design group in Preliminary Design.
“At that time, the team was working an engine design for Boeing’s Y3 project, which would replace the 777-300 and 747 aircraft,” said Ross. “Once the GE9X engine program moved from preliminary design to a real program, I went with it.”
Working two development programs in a row gave Steve the unique opportunity to see the similarities and differences in the engines up close. “The GEnx and GE9X were based on the GE90 architecture, and they both contain many new technologies and firsts for our business—like the composite fan case and TAPS (twin annular pre-swirl) combustor on the GEnx and the 27:1 pressure ratio compressor and greater use of CMCs (ceramic matrix composites) and additive in the GE9X,” explains Steve. “One of the biggest differences that I’ve really enjoyed is our relationship with Boeing’s engineering team, which has been very collaborative.”
For the GE9X, the Engineering team conducted more than five years of rigorous testing on the new technologies that were incorporated into the engine. “I was involved with the compressor studies, including aerodynamic testing at NASA Glenn and high pressure compressor rig tests in Massa, Italy. The GE9X has the highest pressure ratios—at 27:1 in the compressor and 60:1 overall—of any commercial engine. To help design an engine capable of hitting these performance goals is a dream job for any engineer.”
That wasn’t the only highlight for Ross’s efforts on the GE9X program. “Seeing the engine take off on the flying testbed and watching it fly—seeing all those years of work take to the sky—was the one of the best moments for me.”
Working a development program can also pose challenges. “We had several learnings during our testing program. The GE Aviation team along with our Revenue Sharing Participants worked together to pinpoint the root causes. While it took us time, we identified fixes and made the engine more durable and robust. This is one of the rewarding parts about being on a development program.”
“I think of these engines as my engines even though thousands of GE Aviation employees have worked on them. It’s amazing to see all the decisions that were made early in the preliminary design phase coming through to fruition and watch them fly.”