Airworthiness Directive · Amendment 39-18768 · Engine
Rolls-Royce plc Turbofan Engines
Superseded. A later AD replaced this one: AD 2017-08-10. Comply with the one in force.
This AD applies to 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.
We are superseding airworthiness directive (AD) 2014-05-25 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. AD 2014-05-25 required inspections of the low-pressure turbine (LPT) exhaust case and support assembly or tail bearing housing (TBH) to detect cracks or damage. This AD modifies the inspection schedule for the affected engines and adds an optional terminating action. This AD was prompted by RR performing additional analysis of inspection results and determining that the existing inspections need to be modified. We are issuing this AD to correct the unsafe condition on these products.
(1) Within the compliance times and using the service information specified in Table 1 to paragraph (f) of this AD, accomplish on-wing inspections of the TBH features using the following instructions, as applicable.
(i) If during any on-wing inspection of the TBH mount lug run-outs done using the Accomplishment Instructions, paragraph 3.A.(1), of RR Alert Non-Modification Service Bulletin (NMSB) RB.211-72-AG971, Revision 2, dated May 5, 2016, any cracks less than or equal to 2 mm in length are found, remove the engine from service within 10 flight cycles (FCs). If any cracks greater than 2 mm are found, remove the engine from service before further flight.
(ii) If during any on-wing inspection of the TBH mount lug run-outs done using the Accomplishment Instructions, paragraph 3.A.(2), of RR Alert NMSB RB.211-72-AG971, Revision 2, dated May 5, 2016, any crack indications resulting in an inspection signal with an amplitude of 50% full screen height or more are found, remove the engine from service before further flight.
(iii) If during any on-wing inspection of a pre-mod 72-J024 TBH, any crack or damage is found on the TBH mount lug forging leading edge (LE) areas, re-inspect the engine or remove the engine from service in accordance with the Accomplishment Instructions, paragraph 3.A.(3)(t), of RR Alert NMSB RB.211-72-AH154, Revision 5, dated May 5, 2016.
(iv) If during any on-wing inspection of a post-mod 72-J024 TBH, any crack is found on the TBH mount lug forging LE or cutback areas, re-inspect the engine or remove the engine from service in accordance with the Accomplishment Instructions, paragraph 3.A.(3)(t), of RR Alert NMSB RB.211-72-AJ101, dated May 5, 2016.
(2) Within the compliance times and using the service information specified in Table 2 to paragraph (f) of this AD, peform in-shop inspections of the TBH features using the following instructions, as applicable.
(i) If during any in-shop inspection of the TBH, any crack is found on the TBH mount lug or central male catcher run-outs, replace the TBH with a TBH eligible for installation before the engine is returned to service.
(ii) If during any in-shop inspection of the TBH, any crack is found on the top core vanes, reject as unserviceable or repair the TBH in accordance with the Accomplishment Instructions, paragraph 3.C.(1)(f), of RR Alert NMSB RB.211-72-AG971 Revision 2, dated May 5, 2016, before the engine is returned to service.
(iii) If during any in-shop inspection of a pre-mod 72-J024 TBH, any crack or damage is found on the TBH mount lug forging LE areas, reject as unserviceable or repair the TBH in accordance with the Accomplishment Instructions, paragraph 3.B.(2)(u)(ii), of RR Alert NMSB RB.211-72-AH154, Revision 5, dated May 5, 2016, or the Accomplishment Instructions, paragraph 3.C.(1)(f), of RR Alert NMSB RB.211-72-AG971, Revision 2, dated May 5, 2016, before the engine is returned to service.
(iv) If during any in-shop inspection of a post-mod 72-J024 TBH, any crack is found on the TBH mount lug forging LE or cutback areas, repair the TBH in accordance with the Accomplishment Instructions, paragraph 3.B.(2)(u)(ii), of RR Alert NMSB RB.211-72-AJ101, dated May 5, 2016, or the Accomplishment Instructions, paragraph 3.C.(1)(f), of Alert NMSB RB.211-72-AG971, Revision 2, dated May 5, 2016, before the engine is returned to service.
| Affected TBH P/N and feature | Applicable NMSB and paragragph | Alternate NMSB instructions acceptable for prior compliance | Initial inspection | Repeat inspection interval (not to exceed) |
|---|---|---|---|---|
| All—Mount Lug Run-outs | RB.211-72-AG971 Revision 2, Paragraph 3.A | In-shop: RB.211-72-AG971 Revision 2, Paragraph 3.B or 3.C | Before exceeding 2,200 FCs since new | 2,200 FCs. |
| Pre-mod 72-J024 TBH—Mount Lug Forging LE Areas—for a TBH that has not exceeded 900 FCs since new on April 7, 2014 | RB.211-72-AH154, Revision 5, Paragraph 3.A | In-shop: RB.211-72-AH154, Revision 5, Paragraph 3.B., or RB.211-72-AG971 Revision 2, Paragraph 3.C | Before exceeding 1,000 FCs since new | 1,000 FCs. |
| Pre-mod 72-J024 TBH—Mount Lug Forging LE Areas—for a TBH that has exceeded 900 FCs since new on April 7, 2014 | RB.211-72-AH154, Revision 5, Paragraph 3.A | In-shop: RB.211-72-AH154, Revision 5, Paragraph 3.B., or RB.211-72-AG971 Revision 2, Paragraph 3.C | Within 100 FCs after April 7, 2014 | 1,000 FCs. |
| Post-mod 72-J024 TBH—Mount Lug Forging LE and Cutback Areas | RB.211-72-AJ101, Paragraph 3.A | In-shop: RB.211-72-AG971, Revison 2, Paragraph 3.C, or RB.211-72-AJ101, Paragraph 3.B | Before exceeding 1,000 FCs since NMSB RB.211-72-J024 embodiment | 1,000 FCs. |
| Affected TBH P/N and feature | Applicable NMSB and paragraph | Alternate NMSB instructions acceptable for prior compliance | Initial inspection | Repeat inspection interval (not to exceed) |
|---|---|---|---|---|
| All—Mount Lug Run-outs | RB.211-72-AG971, Revision 2, Paragraph 3 | On-wing: RB.211-72-AG971 Rev 2, Paragraph 3.A., or In-shop: RB.211-72-AG971 Revision 2, Paragraph 3.C | Before exceeding 2,200 flight FCs since new | 2,200 FCs. |
| All—Top Core Vanes and Central Male Catcher Run-outs | RB.211-72-AG971, Revision 2, Paragraph 3.C | None | Before exceeding 3,800 FCs since new | 3.800 FCs. |
| Pre-mod 72-J024 TBH—Mount Lug Forging LE Areas—for a TBH which has not exceeded 900 FCs since new on April 7, 2014 | RB.211-72-AH154, Revision 5, Paragraph 3.B | On-wing: RB.211-72-AH154, Revision 5, Section 3.A, or In-shop: RB.211-72-AG971, Revision 2, Paragraph 3.C | Before exceeding 1,000 FCs since new | 1,000 FCs. |
| Pre-mod 72-J024 TBH—Mount Lug Forging LE Areas—for a TBH which has exceeded 900 FCs since new on April 7, 2014 | RB.211-72-AJ101, Paragraph 3.B | On-wing: RB.211-72-AH154 Rev 5, Section 3.A, or In-shop: RB.211-72-AG971, Revision 2, Paragraph 3.C | Within 100 FCs after the effective date of this AD | 1,000 FCs. |
| Post-mod 72-J024 TBH—Mount Lug Forging LE and Cutback Areas | RB.211-72-AJ101, Paragraph 3.B | On-wing: RB.211-72-AJ101, Section 3.A, or In-shop: RB.211-72-AG971 Rev 2, Paragraph 3.C | Before exceeding 1,000 FCs since NMSB RB.211-72-J024 embodiment | 1,000 FCs. |
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
