One issue that led to accidents with the CFM56-3C engine was the failure of fan blades . This mode of failure led to the Kegworth air disaster in 1989 , which killed 47 people and injured 74 more . After the fan blade failed , the pilots mistakenly shut down the wrong engine , resulting in the damaged engine failing completely when powered up for the final approach . Following the Kegworth accident , CFM56 engines fitted to a Dan-Air 737-400 and a British Midland 737-400 suffered fan blade failures under similar conditions ; neither incident resulted in a crash or injuries . After the second incident , the 737-400 fleet was grounded
Kegworth air disaster
Kegworth air disaster
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