Great news! I wonder if the SFC target has been met.
They already have one black mark against them for delaying the whole program due to their "durability issue" that was serious enough to prevent flight test for many months. If they miss on SFC it'd be an even worse black mark against them.
According to lightsaber in the thread of the GE9X certification topic the rumours are that the engine met its targets.
According to what I'm hearing. I called it rumors. I do not have a hundred flights of data to compare with low and high predictions.
What I do not know is durability. I'll flat out say having only 1,000 hours of flight testing count towards the estimated 3,000 hours needed for ETOPs means there were so many changes made to achieve stable operation (fluttering compressor stators=bad) and fuel burn, there was a lot of potential lessons learned that weren't.
The engines are not as proven as the GE-90-115 was as this stage of flight testing. Not even close.
But indications are the performance team is as smug as such a team can be during the "prove it" stage of flight testing. The fact 1,000 hours of testing is acceptable towards ETOPs means "no more fiddling engineers, I mean it!" So the design is frozen. Truly frozen as someone who knows the pain of certification while optimizing performance late in the game can understand.
At this point, no more software updates until ETOPs, on the engine. Zero. Rev x.y.z must have not one bit changed on the GE9x FADAC (the FAA will do bit checks, I'm serious). There will still be airframe "patches."
Winter is coming.