Around eight GE90-115B engines have been identified for immediate attention by GE Aviation.
The findings are based on a probe of a 20 October Thai Airways uncontained high-pressure turbine failure - in reaction the FAA has issued an emergency airworthiness directive (AD) mandating the work.
The failure was found on a Thai flight TG970 as it commenced its take-off roll on a flight bound for Zurich, the take-off was aborted as a result and it is said that debris struck the aircraft fuselage and its other engine.
GE Aviation has said the interstage seal should be removed from affected engines within 25 cycles. The work requires removing the engine.
In an alert service bulletin, GE has listed the engine serial numbers as 907451, 907464, 907504, 907564, 907574, 907599, 907601, and 907618 - these are operated by five different airlines, GE did not name the affected carriers.
“The impacted population of eight engines has the same configuration and similar number of cycles and maintenance history as the event engine,” GE said. “GE Aviation has mobilised technical resources, tooling and spare engines as needed to minimise customer disruption due to the associated engine removals.”