According to already published schedules, GE is expected to run the first version of a new core for the GE9X as early as 2014. A final “Toll Gate 6” decision on freezing the design will likely take place around 2015, with the first engine entering testing in the 2016 time frame. Given this timing, the engine would be tested on GE's 747-400 flying testbed in 2017, with certification the following year.
Last October, GE also revealed that Japanese financial company Mitsui & Co. had become the first strategic partner to join the GE9X engine development effort. By that stage, the GE9X study had been underway for more than 18 months.
Rolls by contrast, has become less bullish about the RB3025 proposal, which focused on a design with an overall pressure ratio of 62:1, and a bypass ratio of 12:1. Although close in thrust to the Trent XWB-97 in development for the Airbus A350-1000, for which Rolls is the exclusive provider, part of Boeing's reluctance to encourage the development of a new, more powerful Rolls engine was that a variant could later be adapted to suit the needs of Airbus, should it subsequently develop a growth variant of the A350-1000 dubbed the A350-1200.
Boeing declines to comment on whether it is about to request board approval for the 777X ATO. It says only that “customers are happy with the airplane design, and we are pleased with where we are in the process. We are aggressively moving forward per our plan and working with our customers on the requirements. While we haven't set a firm time line or launched the program, we've consistently talked about a potential [entry into service] around the end of the decade.”
Pressure on Boeing to act has been growing from some carriers, mostly notably Emirates Airlines, Japan Airlines and British Airways. All Nippon Airways has also been closely involved in the airline group review process for the bigger twin. Commenting last month in Dubai, Emirates President Tim Clark said he expected a launch in “6-9 months,” which would fit the standard Boeing schedule, assuming ATO in April. For example, the board approved offering of the 787 to airlines in December 2003, and the program was officially launched the following April.
It is also uncertain how the prospective go-ahead for the 777X may impact the timing of the 787-10X, a stretch of the 787-9 that received ATO from the board last November. Although Boeing was originally expected to gather orders from a group of launch customers in order to give the official go-ahead for the stretch by this June's Paris air show, the 787 battery troubles and the new focus on the 777X may indicate a shift in priorities.
However, Boeing remains committed to the launch of the -10X, says Randy Tinseth, vice president of marketing for Boeing Commercial Airplanes. “It's not a question of 'if,' but 'when.' It's all coming together in terms of configuration and range,” he says. “We have to work through whether it is 7,000-nm range or 7,100-nm, and so on, but for now our No. 1 priority around the 787 is getting it back to flying.”
Overall, the definition of the -10X is “in really good shape,” he adds. The 777X and 787-10X are still considered strategic stablemates, whether one launches ahead of the other or not. “We think we need both, and that hasn't changed,” Tinseth says.