Airworthiness Directive · Amendment 39-17798 · Rolls-Royce plc Turbofan Engines
Rolls-Royce plc Turbofan Engines
Superseded. A later AD replaced this one: AD 2017-01-01. Comply with the one in force.
This AD applies to Rolls-Royce plc (RR) RB211-Trent 970-84, RB211-Trent 970B-84, RB211-Trent 972-84, RB211-Trent 972B-84, RB211-Trent 977-84, RB211-Trent 977B-84, and RB211-Trent 980-84 turbofan engines.
We are adopting a new airworthiness directive (AD) for all Rolls-Royce plc (RR) RB211-Trent 970-84, RB211-Trent 970B-84, RB211- Trent 972-84, RB211-Trent 972B-84, RB211-Trent 977-84, RB211-Trent 977B-84, and RB211-Trent 980-84 turbofan engines. This AD requires inspections of the low-pressure turbine exhaust case and support assembly or tail bearing housing (TBH) to detect cracks or damage. This AD was prompted by an RR structural re-analysis indicating that the TBH may not retain full limit load capability in all fail-safe conditions. We are issuing this AD to prevent failure of the TBH, resulting in damage to the engine and damage to the airplane.
(1) Accomplish on-wing or in-shop inspections of the TBH as specified in paragraphs (e)(1)(i) through (e)(1)(iv) of this AD.
(i) Perform an inspection of the mount lug run-outs, before exceeding 2,200 flight cycles since new (FCSN). Use Section 3.A., 3.B., or 3.C. of RR Alert Non-Modification Service Bulletin (NMSB) No. RB.211-72-AG971, Revision 1, dated September 27, 2013, to do the inspection. Thereafter, inspect every 2,200 flight cycles (FC).
(ii) For a TBH with 900 FCSN or less on the effective date of this AD, perform an inspection of the mount lug forging leading edge (LE) areas and fail safe catcher, before exceeding 1,000 FCSN. Use Section 3.A., or 3.B. of RR Alert NMSB No. RB.211-72-AH154, Revision 1, dated June 18, 2013; or Section 3.B. or 3.C. of RR Alert NMSB No. RB.211-72-AG971, Revision 1, dated September 27, 2013, to do the inspection. Thereafter, inspect every 1,000 FC.
(iii) For a TBH with more than 900 FCSN on the effective date of this AD, perform an inspection of the mount lug forging LE areas and fail safe catcher, within 100 FC. Use Section 3.A. or 3.B. of RR Alert NMSB No. RB.211-72-AH154, Revision 1, dated June 18, 2013; or Section 3.B. or 3.C. of RR Alert NMSB No. RB.211-72-AG971, Revision 1, dated September 27, 2013, to do the inspection. Thereafter, inspect every 1,000 FC.
(iv) Perform an inspection of the top core vanes, before exceeding 3,800 FCSN. Use Section 3.C. of RR Alert NMSB No. RB.211-72-AG971, Revision 1, dated September 27, 2013, to do the inspection. Thereafter, inspect every 3,800 FC.
(2) If any inspection required by paragraph (e)(1) of this AD fails, remove the TBH from service.
(3) Remove any TBH from service before the TBH exceeds 17,200 FCSN.
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
