Action
Proposed rule; withdrawal.
Summary
The FAA is withdrawing a notice of proposed rulemaking (NPRM) that proposed to supersede Airworthiness Directive (AD) 2022-19-15, which applies to certain International Aero Engines, LLC (IAE LLC) Model PW1100G series engines; and AD 2023-16-07, which applies to certain IAE LLC Model PW1100G series engines and PW1400G series engines. AD 2022-19-15 requires an angled ultrasonic inspection (AUSI) of the high-pressure turbine (HPT) 1st-stage disk and HPT 2nd-stage disk, and replacement if necessary. AD 2023-16-07 requires an AUSI of the HPT 1st-stage hub (also known as the HPT 1st-stage disk) and HPT 2nd-stage hub (also known as the HPT 2nd-stage disk) for cracks, and replacement if necessary, which is terminating action for AD 2022-19- 15. The NPRM was prompted by a manufacturer investigation that determined an increased risk of powder metal anomalies for all powder metal parts in certain powder metal production campaigns, which are susceptible to failure significantly earlier than previously determined. The NPRM would have retained the AUSI requirement for certain HPT 1st-stage and HPT 2nd-stage hubs from AD 2023-16-07. The NPRM would also have required performing an AUSI of the HPT 1st-stage hub, HPT 2nd-stage hub, high-pressure compressor (HPC) 7th-stage integrally bladed rotor (IBR-7), and HPC 8th-stage integrally bladed rotor (IBR-8) for cracks and replacement if necessary. The NPRM would also have required accelerated replacement of the HPC IBR-7, HPC IBR-8, HPC rear hub, HPT 1st-stage hub, HPT 1st-stage air seal, HPT 1st-stage blade retaining plate, HPT 2nd-stage hub, HPT 2nd-stage blade retaining plate, and HPT 2nd-stage rear seal. Since issuance of the NPRM, the FAA has received information that an error was inadvertently included in the compliance times for some of the HPT 1st-stage and 2nd-stage hubs, which would have required removal significantly later than necessary. Accordingly, the NPRM is withdrawn.