A software fault could be to blame for Airbus A220 engine issues which caused the grounding of SWISS’s fleet. The aircraft were grounded in order for thorough engine inspections to take place following a series of engine failures. SWISS’ entire fleet of 29 Airbus A220 aircraft was grounded earlier this month in order for engine inspections to take place. Once on the ground, every single engine underwent a major check. The NTSB has been investigating the engine failures in collaboration with the French BEA. This supposedly allows the engine to behave in a manner that allows destructive vibrations.
Collected and summarized from the source below by Minh Pham https://simpleflying.com/swiss-a220-engine-software/