AD 2021-25-04 Prompted By The Manufacturer Revising The Engine Time Limits Manual (TLM) Life Limits

The FAA is adopting a new airworthiness directive (AD) for certain Rolls-Royce Deutschland Ltd. & Co KG (RRD) Trent 1000 model turbofan engines.

This AD was prompted by the manufacturer revising the engine Time Limits Manual (TLM) life limits of certain critical rotating parts and direct accumulation counting (DAC) data files. This AD requires the operator to revise the airworthiness limitations section (ALS) of their existing approved aircraft maintenance program (AMP) by incorporating the revised tasks of the applicable TLM for each affected model turbofan engine, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective January 19, 2022.

Supplementary Information: EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2020-0243, dated November 5, 2020 (EASA AD 2020-0243) (also referred to as the Mandatory Continuing Airworthiness Information, or the MCAI), to correct an unsafe condition on RRD Trent 1000-AE3, Trent 1000-CE3, Trent 1000-D3, Trent 1000-G3, Trent 1000-H3, Trent 1000-J3, Trent 1000-K3, Trent 1000-L3, Trent 1000-M3, Trent 1000-N3, Trent 1000-P3, Trent 1000-Q3, and Trent 1000-R3 model turbofan engines.

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all RRD Trent 1000-AE3, Trent 1000-CE3, Trent 1000-D3, Trent 1000-G3, Trent 1000-H3, Trent 1000-J3, Trent 1000-K3, Trent 1000-L3, Trent 1000-M3, Trent 1000-N3, Trent 1000-P3, Trent 1000-Q3, and Trent 1000-R3 model turbofan engines. The NPRM published in the Federal Register on August 25, 2021 (86 FR 47417). The NPRM was prompted by the manufacturer revising the engine TLM life limits of certain critical rotating parts and DAC data files.

In the NPRM, the FAA proposed to require the operator to revise the ALS of their existing approved AMP by incorporating the revised tasks of the applicable TLM for each affected model turbofan engine, as specified in an EASA AD. The FAA is issuing this AD to address the unsafe condition on these products. See the MCAI for additional background information.

FMI: www.regulations.gov