Airworthiness Directive · Amendment 39-17275 · Rolls-Royce plc Turbofan Engines
Rolls-Royce plc Turbofan Engines
This AD applies to Rolls-Royce plc (RR) RB211-Trent 970-84 and 972-84 series turbofan engines, all serial numbers.
We are adopting a new airworthiness directive (AD) for certain Rolls-Royce plc (RR) RB211-Trent 900 series turbofan engines. This AD requires inspection of the low pressure turbine (LPT) bearing housing end cover assembly in certain engines and, if necessary, its replacement. This AD was prompted by a Trent 900 engine experiencing a high intermediate pressure vibration fault, along with other fluctuating engine parameters, while in flight. We are issuing this AD to prevent fracture of the oil transfer tube, which could result in uncontained failure of the engine and damage to the airplane.
Before further flight, unless already done, do the following:
(1) Use paragraph 1.A. of RR Alert Non-Modification Service Bulletin (NMSB) RB.211-72-AH051, dated August 3, 2012, or Revision 1, dated September 11, 2012, and RR NMSB RB.211-72-H056, dated August 3, 2012, or Revision 1, dated September 11, 2012, to determine which engine serial numbers to inspect.
(2) Inspect the LPT bearing housing end cover assembly for the presence of a spherical seat, P/N CU38971. For guidance on performing the inspection, see paragraphs 3.A.(5) through 3.A.(8) of the SBs listed in paragraph (e)(1) of this AD.
(3) If, during the inspection required by paragraph (e)(2) of this AD, you find that spherical seat, P/N CU38971, is missing, replace the LPT bearing housing end cover assembly, P/N FW22780, with a part eligible for installation.
After the effective date of this AD:
(1) Do not approve for return to service any airplane with an engine, affected by this AD, installed, unless the engine has passed the inspection required by paragraph (e)(2) of this AD.
(2) Do not install an LPT bearing housing end cover assembly, P/N FW22780, onto any engine required to be inspected by this AD, unless the LPT bearing housing end cover assembly was inspected as required by this AD.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Engines
