Airworthiness Directive · Amendment 39-17183 · Rolls-Royce plc Turbofan Engines
Rolls-Royce plc Turbofan Engines
This AD applies to Rolls-Royce plc (RR) RB211-Trent 875-17, RB211-Trent 877-17, RB211-Trent 884-17, RB211-Trent 884B-17, RB211-Trent 892-17, RB211-Trent 892B-17, and RB211-Trent 895-17 turbofan engines.
We are superseding an existing airworthiness directive (AD) for all Rolls-Royce plc (RR) RB211-Trent 875-17, RB211-Trent 877-17, RB211-Trent 884-17, RB211-Trent 884B-17, RB211-Trent 892-17, RB211- Trent 892B-17, and RB211-Trent 895-17 turbofan engines. That AD currently requires initial and repetitive ultrasonic inspections (UIs) of certain low-pressure (LP) compressor blades identified by serial number (S/N). This new AD requires the same actions but expands the population of blades. This AD was prompted by the need to add the inspections of the LP compressor blades listed by S/N in Appendices 3H through 3L of RR plc Alert Service Bulletin (ASB) No. RB.211-72-AG244, Revision 4, dated December 22, 2011. We are issuing this AD to prevent multiple LP compressor blades from failing due to blade root cracks, which could lead to uncontained engine failure and damage to the airplane.
(1) Perform an initial ultrasonic inspection (UI) of the affected LP compressor blades identified by S/N in Appendices 3A through 3L of RR ASB No. RB.211-72-AG244, Revision 4, dated December 22, 2011. Use Table 1 to paragraph (e) of this AD to determine your initial inspection threshold.
| Appendix number of RR ASB Number RB.211-72-AG244, Revision 4, that identifies affected LP compressor blades by S/N | Initial inspection threshold |
|---|---|
| 3A and 3B | Within 70 flight cycles after the effective date of this AD. |
| 3C | Within 10 months after the effective date of this AD. |
| 3D | Within 22 months after the effective date of this AD. |
| 3E | Within 34 months after the effective date of this AD. |
| 3F | Within 46 months after the effective date of this AD. |
| 3G | Within 58 months after the effective date of this AD. |
| 3H | Within 70 months after the effective date of this AD. |
| 3I | Within 82 months after the effective date of this AD. |
| 3J | Within 94 months after the effective date of this AD. |
| 3K | Within 106 months after the effective date of this AD. |
| 3L | Within 118 months after the effective date of this AD. |
(2) Thereafter, perform repetitive UIs of the affected LP compressor blades within every 100 flight cycles.
(3) Use paragraph 3.A.(2) of Accomplishment Instructions of RR ASB No. RB.211-72-AG244, Revision 4, dated December 22, 2011, and paragraphs 1. through 3.B. of Appendix 1 of that ASB, or paragraphs 3.B.(3) of Accomplishment Instructions of RR ASB No. RB.211-72-AG244, Revision 4, dated December 22, 2011, and paragraphs 1. through 3.C. of Appendix 2 of that ASB, to perform the UIs. Prior to inspecting the blades per paragraph 3.B.(3) of the Accomplishment Instructions remove the air intake fairing/spinner and spinner extension and annulus fillers.
(4) Do not return to service any engine with blades that failed the inspection required by this AD.
(5) For blades that are removed from the engine and pass inspection, re-apply dry film lubricant before re-installing the blades.
After the effective date of this AD, do not install any affected LP compressor blade that has reached the initial inspection threshold in Table 1 to paragraph (e) of this AD, unless it has passed the UI 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
