Monday, September 24, 2012
FAA Issues Airworthiness Directive for GEnx Engines
FAA issued a new airworthiness directive (AD) calling for ultrasonic inspections (UI) of all GE GEnx-1B and 2B engines.
The AD was the result of a recommendation from the National Transportation Safety Board (NTSB) following a string of recent incidents where GEnx engines installed on Boeing 787s and a 747-8 experienced engine failure from cracks on the fan mid shafts (FMS).
“We consider this AD interim action. Root cause is still under investigation, but the failure of the FMS is likely due to environmentally assisted cracking; a type of corrosive cracking that is time- dependent,” said FAA in its AD Friday.
NTSB said Boeing and GE completed initial inspections on all affected engines in-service as of September 19, 2012.
FAA estimates there are still 11 GE GEnx turbofan engines installed on airplanes of U.S. registry that need to undergo ultrasonic inspections.
Additionally, FAA is calling for repetitive UIs for the FMS every 90 days “since-last-inspection.”
"We appreciate the response of both FAA and GE in recognizing this serious safety issue," said NTSB Chairman Deborah A. P. Hersman. "We continue to work with all those involved in these investigations."