Action
Final rule; request for comments.
Summary
The FAA is superseding Airworthiness Directive (AD) 2020-24- 08, which applied to certain Rolls-Royce Deutschland Ltd & Co KG (RRD) Model RB211 Trent 768-60, 772-60, 772B-60, and 772C-60 engines. AD 2020-24-08 required replacement of high-pressure turbine (HPT) blades with parts eligible for installation before exceeding specified flight cycles since new. Since the FAA issued AD 2020-24-08, RRD published updated service material to revise the applicability for certain engines and introduce a terminating action for the repetitive replacements of the HPT blades. This AD requires removal from service of certain engines and replacement of the HPT blades before exceeding specified flight cycles since new. This AD also allows for a modification of the engine that would eliminate the need for the repetitive replacements of the HPT blades. The FAA is issuing this AD to address the unsafe condition on these products.