SUPPLEMENTARY INFORMATION:

Comments Invited

The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2024-2142; Project Identifier AD-2024-00033-A” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may revise this proposal because of those comments.

Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM.

Confidential Business Information

CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Fred Caplan, Aviation Safety Engineer, FAA, 1701 Columbia Avenue, College Park, GA 30337. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking.

Background

The FAA issued an NPRM to amend 14 CFR part 39 by adding an AD that would supersede AD 2020-26-16, Amendment 39-21371 (86 FR 3769, January 15, 2021) (AD 2020-26-16), for certain Piper Model PA-28-151, PA-28-161, PA-28-181, PA-28-235, PA-28R-180, PA-28R-200, PA-28R-201, PA-28R-201T, PA-28RT-201, PA-28RT-201T, PA-32-260, PA-32-300, PA-32R-300, PA-32RT-300, and PA-32RT-300T airplanes. AD 2020-26-16 requires calculating the factored service hours (FSH) for each main wing spar to determine when an inspection is required, inspecting the lower main wing spar bolt holes for crack(s), and replacing any cracked main wing spar. Since the FAA issued AD 2020-26-16, the FAA evaluated the reports required by AD 2020-26-16 and determined that repetitive inspections of the lower main wing spar bolt holes for crack(s) and non-crack damage (including deep scratches, gouges, and thread marks) and replacement or modification of the main wing spar should be required, CSH should be used instead of FSH to determine times for required actions for each main wing spar, and that certain airplanes should be removed from the ( printed page 88174) applicability and a new airplane model added to the applicability.

The NPRM published in the Federal Register on September 23, 2024 (89 FR 77457). In the NPRM, the FAA proposed to require calculating the CSH for each main wing spar; repetitively inspecting the lower main wing spar bolt holes for crack(s) and non-crack damage and taking corrective actions as needed; replacing or modifying main wing spars at a specified time; and reporting inspection results to Piper and the FAA if any cracks are found during any inspection. In the NPRM, the FAA also proposed to revise the applicability by removing certain airplanes and adding a new airplane model. The FAA is proposing this AD to detect and correct fatigue cracks in the lower main wing spar cap bolt holes. The unsafe condition, if not addressed, could result in a wing separating from the fuselage in flight.

Actions Since the NPRM Was Issued

Since issuance of the NPRM, the FAA received a request from Piper to extend the comment period. The commenter stated that the NPRM is complex and could drive substantial costs, among other things. In addition, the commenter stated that two significant hurricanes have prevented operators from performing a dedicated review of the NPRM. To be able to prepare informed and meaningful comments Piper requested an extension of 30 days to the comment period.

The FAA has determined that it is appropriate to extend the comment period for the NPRM to give all interested persons additional time to examine the proposed requirements and submit comments. The FAA has determined that extending the comment period an additional 30 days will not compromise the safety of the affected airplanes.

Extension of Comment Period

The FAA has reviewed the request for extension of the comment period for this notice. The commenter has shown a substantive interest in the proposed policy and good cause for the extension of the comment period. Therefore, in accordance with 14 CFR 11.47(c), the FAA has determined that an extension of the comment period for an additional 30 days to December 9, 2024, is consistent with the public interest, and that good cause exists for taking this action.

Accordingly, the comment period for Docket No. FAA-2024-2142 is extended until December 9, 2024.

Because no other portion of the proposal or other regulatory information has been changed, the entire proposal is not being republished.

Issued under authority provided by 49 U.S.C. 106(g), 40113, and 44701.