airworthiness · Rule · Final rule. · Published 2021-05-20 · Effective 2021-06-24 · 86 FR 27264
Document
Document number
2021-10607
Federal Register citation
86 FR 27264
Type
Rule
Action
Final rule.
Category
airworthiness
Publication date
2021-05-20
Effective date
2021-06-24
FAA docket
Docket No. FAA-2019-0568
Abstract
The FAA is adopting a new airworthiness directive (AD) for all CFM International, S.A. (CFM) CFM56-5B and CFM56-7B model turbofan engines with a certain high-pressure turbine (HPT) inner stationary seal installed. This AD was prompted by cracks found in the rotating air HPT front seal. This AD requires removal, inspection, and replacement of the affected HPT inner stationary seal and, depending on the findings, replacement of the rotating air HPT front seal, HPT rotor blades, and No. 3 ball bearing. The FAA is issuing this AD to address the unsafe condition on these products.