Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for all Pratt & Whitney PW4050, PW4052, PW4056, PW4060, PW4060A, PW4060C, PW4062, PW4062A, PW4152, PW4156, PW4156A, PW4158, PW4160, PW4460, PW4462, and PW4650 turbofan engines, including models with any dash number suffix. This AD was prompted by reports of five engine in-flight shutdowns and seven unplanned engine removals. This AD requires inspections, cleaning, and engine modifications to address coking in the No. 4 bearing compartment and in the oil pressure and scavenge tubes. We are issuing this AD to prevent an engine fire, a fractured fan drive shaft, and damage to the airplane.