Airworthiness Directive · Amendment 39-17290 · Rolls-Royce plc Turbofan Engines
Rolls-Royce plc Turbofan Engines
This AD applies to all Rolls-Royce plc (RR) RB211-524G2-19; RB211-524G2-T-19; RB211-524G3-19; RB211-524G3-T-19; RB211-524H2-19; RB211-524H2-T-19; RB211-524H-36; RB211-524H-T-36; RB211-535E4-37; RB211-535E4-B-37; RB211-535E4-B-75; and RB211-535E4-C-37 turbofan engines with intermediate-pressure (IP) discs listed in Appendix 1 and Appendix 2 of RR Alert Service Bulletin (ASB) No. RB.211-72-AG493, Revision 2, dated October 12, 2012.
We are adopting a new airworthiness directive (AD) for all Rolls-Royce plc (RR) RB211-524G2-19; RB211-524G2-T-19; RB211-524G3-19; RB211-524G3-T-19; RB211-524H2-19; RB211-524H2-T-19; RB211-524H-36; RB211-524H-T-36; RB211-535E4-37; RB211-535E4-B-37; RB211-535E4-B-75; and RB211-535E4-C-37 turbofan engines. This AD was prompted by an investigation by RR concluding that certain intermediate-pressure (IP) turbine discs produced before 1997 by a certain supplier may contain steel inclusions. This AD requires removal of the affected IP turbine discs to inspect them for steel inclusions, and removal of the affected discs from service if they fail the inspection. This AD also requires removal from service of some IP turbine discs at reduced life limits. We are issuing this AD to prevent uncontained IP turbine disc failure, engine failure, and damage to the airplane.
Unless already done, do the following actions.
After the effective date of this AD, use Appendix 1 and Appendix 2 of RR ASB No. RB.211-72-AG493, Revision 2, dated October 12, 2012, to determine if the IP turbine disc is below or above the inspection threshold.
(1) If below the inspection threshold, clean and perform a Superconductive Quantitative Inductive Device (SQUID) inspection of the disc at the next shop visit or before the disc reaches the inspection threshold, whichever is later. Use Appendix 4 of RR ASB No. RB.211-72-AG493, Revision 2, dated October 12, 2012, to perform the SQUID inspection.
(2) If above the inspection threshold, clean and perform a SQUID inspection of the disc if in the shop or, at the next shop visit, whichever occurs first. Use Appendix 4 of RR ASB No. RB.211-72-AG493, Revision 2, dated October 12, 2012, to perform the SQUID inspection.
(3) Do not return to service any disc that fails the inspection required by this AD.
(4) Instead of performing the inspection required by paragraph (f), you may replace an affected disc with a part eligible for installation. See Appendix 1 and Appendix 2 of RR ASB No. RB.211-72-AG493, Revision 2, dated October 12, 2012, to determine if you have an affected disc.
(1) After the effective date of this AD, use Appendix 2 of RR ASB No. RB.211-72-AG493, Revision 2, dated October 12, 2012, to determine the maximum life (in cycles) of affected IP turbine disc(s).
(2) Remove from service any disc at the next shop visit or before it exceeds its maximum life (in cycles), whichever is later, as found in Appendix 2 of RR ASB No. RB.211-72-AG493, Revision 2, dated October 12, 2012.
(3) Do not return to service any disc that exceeds its maximum life (in cycles) as found in Appendix 2 of RR ASB No. RB.211-72-AG493, Revision 2, dated October 12, 2012, unless it has passed the inspection required by paragraph (f) of the AD.
For purposes of this AD, a shop visit is defined as induction into the shop where the IP and low pressure (LP) turbine module is removed from the engine, and any casing is removed from the IP and LP turbine module.
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.
