AD 2020-21-13 Prompted By The Detection Of Melt-Related Freckles In The Billet

The FAA is adopting a new airworthiness directive (AD) for certain General Electric Company (GE) GE90-110B1 and GE90-115B model turbofan engines.

This AD was prompted by the detection of melt-related freckles in the billet, which may reduce the life limits of certain highpressure turbine (HPT) rotor stage 2 disks and certain rotating compressor discharge pressure (CDP) HPT seals. This AD requires the replacement of the affected HPT rotor stage 2 disks and rotating CDP HPT seals. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective November 17, 2020.

Supplementary Information: The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an  AD that would apply to certain GE GE90-110B1 and GE90-115B model turbofan engines. The NPRM published in the Federal Register on August 13, 2020 (85 FR 49322). The NPRM was prompted by the detection of melt-related freckles in the billet, which may reduce the life limits of certain HPT rotor stage 2 disks and certain rotating CDP HPT seals. The NPRM proposed to require the replacement of certain HPT rotor stage 2 disks and certain rotating CDP HPT seals. The FAA is issuing this AD to address the unsafe condition on these products.

FMI: www.regulations.gov