Summary
The FAA proposes to adopt a new airworthiness directive (AD) for Pratt & Whitney PW4000 series turbofan engines. This proposed AD would require a one-time visual inspection of the No. 3 bearing oil pressure tube, part number (P/N) 51J041-01, P/N 50J604-01, or P/N 50J924-01. Tubes that are found cracked or repaired would be required to be removed from service. This proposed AD would also prohibit repaired tubes from being installed. This proposed AD results from one report of a repaired No. 3 bearing oil tube that caused an engine in- flight shutdown, seven reports of repaired No. 3 bearing oil pressure tubes found cracked that led to unscheduled engine removals, and one report of a test cell event from a repaired tube that cracked. We are proposing this AD to prevent cracking of No. 3 bearing oil pressure tubes which could result in internal oil fire, failure of the high- pressure turbine (HPT) disks, uncontained engine failure, and damage to the airplane.