Airworthiness Directive · Amendment 39-21495 · Turbine engine combustion section
Rolls-Royce Deutschland Ltd & Co KG (Type Certificate Previously Held by Rolls-Royce plc) Turbofan Engines
This AD applies to Rolls-Royce Deutschland Ltd & Co KG (Type Certificate previously held by Rolls-Royce plc) RB211 Trent 768-60, RB211 Trent 772-60, and RB211 Trent 772B-60 model turbofan engines equipped with:
(1) Low-pressure compressor (LPC) blade, with part number (P/N) FW23741 or P/N KH23403, and a serial number (S/N) listed in Appendix 1 of Rolls-Royce (RR) Trent 700 Series Propulsion Systems Alert Non-Modification Service Bulletin (NMSB) RB.211-72-AK492, Revision 1, dated November 30, 2020 (NMSB RB.211-72-AK492), installed; or
(2) LPC disk, with P/N FK22541, P/N FW16259 or P/N KH20338, and an S/N listed in Appendix 2 of NMSB RB.211-72-AK492.
The FAA is adopting a new airworthiness directive (AD) for certain Rolls-Royce Deutschland Ltd & Co KG (RRD) RB211 Trent 768-60, RB211 Trent 772-60, and RB211 Trent 772B-60 model turbofan engines. This AD was prompted by maintenance that resulted in damage to certain low-pressure compressor (LPC) blades, resulting in increased susceptibility to cracking in the LPC blade root. This AD requires initial and repetitive inspections of the blade root of certain LPC blades and re-lubrication of the LPC blades and LPC disk. Depending on the results of the inspections, this AD requires replacement of the LPC blades. As a terminating action to the inspection and re-lubrication requirements, this AD requires restoration of the LPC blade as well as examination and re-lubrication of the LPC disk. The FAA is issuing this AD to address the unsafe condition on these products.
(1) Within 200 engine flight cycles (FCs) after the effective date of this AD, perform an initial on-wing ultrasonic inspection of the blade root of each LPC blade using the Accomplishment Instructions, paragraph 3.A.(3)(a) through (c) of NMSB RB.211-72-AK492.
(2) Within 200 engine FCs after the effective date of this AD, re-lubricate each LPC blade and LPC disk using the Accomplishment Instructions, paragraph 3.A.(4) of NMSB RB.211-72-AK492.
(3) Repeat the inspection of each LPC blade and the re-lubrication of each LPC blade and LPC disk required by paragraphs (g)(1) and (2) of this AD at intervals not to exceed 350 engine FCs since the last inspection and re-lubrication.
(4) If, during any inspection required by paragraph (g)(1) or (3) of this AD, an LPC blade is found with unacceptable indications as specified in Appendix 4, paragraph 3 of NMSB RB.211-72-AK492, before next flight, remove and replace the LPC blade with a part eligible for installation.
As a mandatory terminating action to the inspections and re-lubrications required by paragraphs (g)(1) through (3) of this AD, at the next engine shop visit after the effective date of this AD, restore the LPC blades to a serviceable condition and examine and re-lubricate the LPC disk using the Accomplishment Instructions, paragraph 3.A or 3.B of RR Trent 700 Alert NMSB RB.211-72-AK522, Revision 1, dated November 30, 2020.
(1) For the purposes of this AD, an “engine shop visit” is the induction of an engine into the shop for maintenance involving the separation of pairs of major mating engine flanges, with the exception of the separation of engine flanges solely for the purpose of transporting the engine without subsequent maintenance.
(2) For the purposes of this AD, a part eligible for installation is an LPC blade, with:
(i) A P/N FW23741 or P/N KH23403, with an S/N listed in Appendix 1 of RR Trent 700 Series Propulsion Systems Alert NMSB RB.211-72-AK492, that has passed the inspections required by paragraph (g)(1) or (3) of this AD, or has zero flight cycles since new; or
(ii) A P/N FW23741 or P/N KH23403, with an S/N that is not listed in Appendix 1 of RR Trent 700 Series Propulsion Systems Alert NMSB RB.211-72-AK492.
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.
