Originally Posted by
Downwind Lander
The $65,000 question must be: how many such engines are in service now?
The B787 fleet is not small by any accepted measure; over 440 in service. Neither is the General Electric GEnx engine pool small; there are well over 1,000 GEnx engines currently in service around the world (it's one of the fastest selling airplane engines of all time) and it has accumulated around 7 million operating hours.
The inflight shut-down (IFSD) requirement for engines under 330 minutes Extended-range Twin-engine Operational Performance Standards is 0.01 IFSDs per 1000 engine hours, which is the same as 10 shutdowns per million hours. To be clear, that means, on the average, one inflight engine shut-down every 100,000 engine hours. The General Electric GEnx engine exceeds that reliability requirement by more than a factor of three. Its reliability is at or about on a par with more "mature" engines such as the CFM CF6-80C2 (Airbus A300, Airbus A310, Boeing B767), the General Electric GE90 (Boeing B777) and the Pratt and Whitney PW4000 (Airbus A300, Airbus A310, Boeing B747).