PRODUCT: Certain serial numbers (S/Ns) of Rolls-Royce plc (RR) RB211-Trent 768-60, 772-60, and 772B-60 turbofan engines. SUBJECT: Airworthiness Directive 2012-25-08 ACTION: Final Rule
SUMMARY: This AD requires initial and repetitive on-wing or in-shop inspections of the high pressure/intermediate pressure (HP/IP) turbine bearing support oil feed tube outer heat shield. This AD also requires installation of a revised HP/IP turbine bearing support structure as terminating action to the repetitive inspections of the HP/IP turbine bearing support oil feed tube outer heat shield.
This AD was prompted by a report of high oil consumption due to an oil leak from the HP/IP turbine bearing support oil feed tube. The FAA is issuing this AD to prevent failure of the HP turbine disc, uncontained engine failure, and damage to the airplane.
DATES: This AD becomes effective January 10, 2013.