AD 2024-11-01

This AD is effective July 3, 2024.

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2024-0221; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this final rule, any comments received, and other information. The address for Docket Operations is U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.

Dan Rodina, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 206-231-3225; email dan.rodina@faa.gov.

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2021-21-02, Amendment 39-21762 (86 FR 62898, November 15, 2021) (AD 2021-21-02). AD 2021-21-02 applied to certain Airbus SAS Model A318, A319, A320, A321, A330-200, A330-200 Freighter, A330-300, A330-800, A330-900, A340-200, A340-300, A340-500, A340-600, and A380-800 series airplanes. The NPRM published in the Federal Register on February 9, 2024 (89 FR 9074). The NPRM was prompted by a determination that the on-wing preservation procedures originally provided in that AD did not ensure the expected preservation of the battery capacity. In the NPRM, the FAA proposed to add Model A300 series airplanes; Model A300 B4-600, B4-600R, and F4-600R series airplanes, and Model A300 C4-605R Variant F airplanes (collectively called Model A300-600 series airplanes); Model A310 series airplanes; and Model A350-941 and -1041 airplanes to the applicability. The FAA proposed that the superseding AD would retain none of the requirements of AD 2021-21-02. The FAA proposed to require replacing each affected part with a serviceable part before release to service of an airplane after a storage or parking period, as applicable. The FAA is issuing this AD to address reduced battery endurance performance, which could possibly result in failure to supply the minimum essential electrical power during abnormal or emergency conditions.

The FAA received comments from Air Line Pilots Association, International (ALPA), who supported the SNPRM/NPRM without change.

The FAA received additional comments from American Airlines (AA) and United Airlines (UAL). The following presents the comments received on the NPRM and the FAA's response to each comment.

AAL requested clarification of “parking and storage” as intended by the proposed AD. The commenter asked whether “parking and storage” included extended heavy maintenance checks, such as an S-check that is abnormally extended beyond the 6-month time-limit due to inspection findings or material sourcing issues, or extended downtime for aircraft repair or modification such as a large repair for aircraft tug collision damage or a large-scale interior modification.

The FAA agrees to clarify. It is the responsibility of the operator to apply the relevant instructions provided in the aircraft maintenance manual (AMM) related to extended heavy maintenance checks or downtime for aircraft repair or modification. A dedicated preservation regime shall be defined in line with the maintenance activity requirements (for example, the need to keep batteries connected), based upon the applicable AMM parking and storage procedures. If a battery meets the definition of a “serviceable part” as specified in paragraphs (g)(2) and (3) of this AD, then the requirement to replace after “parking and storage” does not apply because it is not an affected part. However, if the battery meets the definition of an “affected part” as specified in paragraph (g)(1) of this AD, the requirement to replace after “parking and storage” does apply.

UAL requested that in the future an attempt is made to include PMA parts during “initial release” as opposed to having two ADs (UAL stated “no change to this AD”).

The FAA recognizes the efficiency of a single AD, but in the future, may or may not issue separate ADs when PMA parts and non-PMA parts ( i.e., original equipment manufacturer (OEM) parts) are involved, depending on potential implementation issues and what is in the best interest of safety.

UAL stated that Docket FAA-2024-0029 indicated it applied to the PMA batteries, as does the NPRM.

The FAA acknowledges that the NPRM that published in the Federal Register on January 22, 2024 (89 FR 3897), for Docket FAA-2024-0029, inadvertently referred to PMA batteries. However, in the final rule, AD 2024-08-08, Amendment 39-22741 (89 FR 35695, May 2, 2024) (AD 2024-08-08), the FAA removed references to PMA batteries. Only this AD is applicable to PMA batteries.

Note 1 to paragraph (h) of the proposed AD specifies that airplanes on which a battery is replaced with a serviceable non-PMA Ni-Cd battery are affected by AD 2021-20-08, Amendment 39-21746 (86 FR 57025, October 14, 2021), which provides requirements for non-PMA Ni-Cd batteries. However, the FAA has superseded AD 2021-20-08 with AD 2024-08-08. AD 2024-08-08 adds airplanes to the applicability and requires replacement of certain affected parts ( i.e., certain non-PMA Ni-Cd batteries) with serviceable parts as a precondition for return to service of airplanes from storage or parking, as specified in European Union Aviation Safety Agency (EASA) AD 2023-0196, dated November 10, 2023. You may examine the AD docket for AD 2024-08-08 at regulations.gov under Docket No. FAA-2024-0029. The FAA has added a reference to AD 2024-08-08 to Note 1 to paragraph (h) of this AD.

The FAA reviewed the relevant data, considered any comments received, and determined that air safety requires adopting this AD as proposed. Accordingly, the FAA is issuing this AD to address the unsafe condition on these products. Except for minor editorial changes, and any other changes described previously, this AD is adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator.

The FAA estimates that this AD affects 1,814 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD:

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII: Aviation Programs, describes in more detail the scope of the Agency's authority.

The FAA is issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701: General requirements. Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

This AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866,

(2) Will not affect intrastate aviation in Alaska, and

(3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

1. The authority citation for part 39 continues to read as follows:

2. The FAA amends § 39.13 by:

a. Removing Airworthiness Directive (AD) 2021-21-02, Amendment 39-21762 (86 FR 62898, November 15, 2021); and

b. Adding the following new AD: