Federal Aviation Administration March 24, 2023 – Federal Register Recent Federal Regulation Documents

The FAA is superseding Airworthiness Directive (AD) 2012-02-07 for certain General Electric Company (GE) CF6-45 and CF6-50 series model turbofan engines with a specified low-pressure turbine (LPT) rotor stage 3 disk installed. AD 2012-02-07 required inspections of high-pressure turbine (HPT) and LPT rotors, engine checks, vibration surveys, an optional LPT rotor stage 3 disk removal after a failed HPT blade borescope inspection (BSI) or a failed engine core vibration survey, established a lower life limit for the affected LPT rotor stage 3 disks, and required removing these disks from service at times determined by a drawdown plan. This AD was prompted by the occurrence of four events of separation of the LPT rotor assembly, which resulted in the LPT rotor assembly departing the rear of the engine. This AD requires inspections of HPT and LPT rotor stage 1 and stage 2 blades, vibration surveys, and use of a lower life limit for the affected LPT rotor stage 3 disks and, as terminating action to the inspections, engine checks, and vibration surveys, this AD requires removal and replacement of the LPT rotor stage 3 disk with a redesigned LPT rotor stage 3 disk. This AD also requires revising the compliance time of the drawdown plan for the removal and replacement of the LPT rotor stage 3 disk and prohibits the installation or reinstallation of certain LPT rotor stage 3 disks. The FAA is issuing this AD to address the unsafe condition on these products.

This amendment adopts miscellaneous amendments to the required IFR (instrument flight rules) altitudes and changeover points for certain Federal airways, jet routes, or direct routes for which a minimum or maximum en route authorized IFR altitude is prescribed. This regulatory action is needed because of changes occurring in the National Airspace System. These changes are designed to provide for the safe and efficient use of the navigable airspace under instrument conditions in the affected areas.

The FAA proposes to adopt a new airworthiness directive (AD) for all CFM International, S.A. (CFM) LEAP-1A23, LEAP-1A24, LEAP- 1A24E1, LEAP-1A26, LEAP-1A26CJ, LEAP-1A26E1, LEAP-1A29, LEAP-1A29CJ, LEAP-1A30, LEAP-1A32, LEAP-1A33, LEAP-1A33B2, and LEAP-1A35A (LEAP-1A) model turbofan engines. This proposed AD was prompted by a manufacturer investigation that revealed that certain high-pressure turbine (HPT) rotor stage 1 disks (HPT stage 1 disks), forward outer seals, and stages 6-10 compressor rotor spools were manufactured from material suspected to have reduced material properties due to iron inclusion. This proposed AD would require replacement of certain HPT stage 1 disks, forward outer seals, and stages 6-10 compressor rotor spools. The FAA is proposing this AD to address the unsafe condition on these products.

This action establishes Class E airspace extending upward from 700 feet above the surface at Escalante Municipal Airport, UT. This action will support the airport's transition from visual flight rules (VFR) to instrument flight rules (IFR).