The U.S. Federal Aviation Administration (FAA) will not grant a type certificate for Boeing’s 777-9 until it approves a redesigned mid-seal for the aircraft’s GE Aerospace GE9X engines. The seal connects sections of the engine. A crack in the original seal was found during a shop visit earlier this year, revealing a durability issue.
GE Aerospace has developed a new design and completed internal testing. In the third quarter, it began shipping engines with the updated seal to Boeing. The issue has delayed the crucial Extended-range Twin-engine Operational Performance Standards (ETOPS) flight-test program, but Boeing and GE do not expect it to change the target for the first 777-9 delivery in 2027. GE is seeking FAA approval for the new component by the end of 2026.