Airworthiness Directive · Amendment 39-18793 · Rolls-Royce plc Turbofan Engines
Rolls-Royce plc Turbofan Engines
Superseded. A later AD replaced this one: AD 2020-06-16. Comply with the one in force.
This AD applies to Rolls-Royce plc (RR) RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines, with low-pressure (LP) compressor blade, part number (P/N) FK23411, FK25441, FK25968, FW11901, FW15393, FW23643, FW23741, FW23744, KH23403, or KH23404, installed.
We are superseding airworthiness directive (AD) 2014-16-10 for all Rolls-Royce plc (RR) RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines. AD 2014-16-10 required initial and repetitive ultrasonic inspections (UIs) of the affected low-pressure (LP) compressor blades. This AD requires the UIs in AD 2014-16-10 while reducing the inspection threshold. This AD was prompted by revised service information to reduce the inspection threshold for UI of the LP compressor blades. We are issuing this AD to correct the unsafe condition on these products.
(i) After the effective date of this AD, for LP compressor blades that have accumulated less than 1,800 cycles since new (CSN) or cycles since last inspection (CSLI), perform a UI of each LP compressor blade before the blade exceeds 2,400 CSN or CSLI. Repeat the UI of the blade before exceeding 2,400 CSLI.
(ii) For any LP compressor blade that exceeds 1,800 CSN on the effective date of this AD, inspect the blade before exceeding 600 flight cycles after the effective date of this AD or before exceeding 3,600 CSN, whichever occurs first. Thereafter, perform the repetitive inspections before exceeding 2,400 CSLI.
(iii) For any LP compressor blade that exceeds 2,200 CSLI on September 23, 2014 (the effective date of AD 2014-16-10), inspect the blade before exceeding 3,000 CSLI or before further flight, whichever occurs later. Thereafter, perform the repetitive inspections before exceeding 2,400 CSLI.
(iv) Use paragraph 3, excluding subparagraphs 3.C.(2)(b), 3.D.(2), and 3.G, of RR Alert Non-Modification Service Bulletin (NMSB) RB.211-72-AH465, Revision 2, dated May 11, 2016, to perform the inspections required by this AD.
(i) After the effective date of this AD, LP compressor blade, P/N FK23411, FK25441, FK25968, FW11901, FW15393, FW23643, FW23741, FW23744, KH23403, or KH23404, that has accumulated at least 2,400 CSN or CSLI is eligible for installation if the blade has passed the UI required by this AD.
(ii) Reserved.
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.
