Airworthiness Directives; The Boeing Company Airplanes

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Federal RegisterOct 23, 2024
89 Fed. Reg. 84457 (Oct. 23, 2024)
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    Department of Transportation Federal Aviation Administration
  • 14 CFR Part 39
  • [Docket No. FAA-2024-2412; Project Identifier AD-2024-00535-T; Amendment 39-22868; AD 2024-21-01]
  • RIN 2120-AA64
  • AGENCY:

    Federal Aviation Administration (FAA), DOT.

    ACTION:

    Final rule; request for comments.

    SUMMARY:

    The FAA is adopting a new airworthiness directive (AD) for all The Boeing Company Model 717-200 airplanes. This AD was prompted by a report of cracks found in the rear spar lower cap forward leg and lower aft skin of the right wing, during investigation of a fuel leak. This AD requires repetitive inspections for any fuel leak or crack of the lower aft skins, external doublers, and rear spar lower caps of the left and right wings, and corrective actions and inspection reports if necessary. The FAA is issuing this AD to address the unsafe condition on these products.

    DATES:

    This AD is effective November 7, 2024.

    The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of November 7, 2024.

    The FAA must receive comments on this AD by December 9, 2024.

    ADDRESSES:

    You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:

    • Federal eRulemaking Portal: Go to regulations.gov. Follow the instructions for submitting comments.
    • Fax: 202-493-2251.
    • Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
    • Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

    AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2024-2412; 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 street address for Docket Operations is listed above.

    Material Incorporated by Reference:

    • For Boeing material identified in this AD, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone 562-797-1717; websitemyboeingfleet.com.
    • You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195. It is also available atregulations.gov under Docket No. FAA-2024-2412.

    FOR FURTHER INFORMATION CONTACT:

    Wayne Ha, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 562-627-5238; email: Wayne.Ha@faa.gov.

    SUPPLEMENTARY INFORMATION:

    Comments Invited

    The FAA invites you to send any written data, views, or arguments about this final rule. Send your comments to an address listed under the ADDRESSES section. Include Docket No. FAA-2024-2412 and Project Identifier AD-2024-00535-T at the beginning of your comments. The most helpful comments reference a specific portion of the final rule, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this final rule 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 final rule.

    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 AD 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 AD, 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 AD. Submissions containing CBI should be sent to Wayne Ha, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 562-627-5238; email: Wayne.Ha@faa.gov. Any commentary that the FAA receives that is not specifically designated as CBI will be placed in the public docket for this rulemaking.

    Background

    The FAA has received a report indicating that, during investigation of a fuel leak, a crack was found in the rear spar lower cap forward leg of the right wing. Subsequent inspections revealed multiple cracks in the wing lower aft skin in the same general area as the cracks found in the spar cap, including one approximately 7 inches in length that is not capable of sustaining a limit load event. This condition, if not addressed, could lead to reduced structural integrity of the airplane and loss of control of the airplane, which could result in a catastrophic event. The FAA is issuing this AD to address the unsafe condition on these products.

    FAA's Determination

    The FAA is issuing this AD because the agency has determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.

    Material Incorporated by Reference Under 1 CFR Part 51

    The FAA reviewed Boeing Multi Operator Message MOM-MOM-24-0482-01B, dated September 13, 2024. This material specifies procedures for repetitive general visual inspections of the lower aft skins and external doublers of the left and right wings for any fuel leak; repetitive general visual inspections of the rear spar lower caps of the left and right wings for any fuel leak; repetitive surface eddy current high frequency inspections of the rear spar lower caps of the left and right wings for any crack; repetitive surface eddy current high frequency inspections of the lower aft skins of the left and right wings for any crack; and obtaining and following approved repair instructions if any fuel leak or crack is detected during any inspection. This material is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

    AD Requirements

    This AD requires accomplishing the actions specified in the material already described. This AD also requires sending the inspection results to the airplane manufacturer if any crack or fuel leak is found during any inspection.

    Interim Action

    The FAA considers this AD to be an interim action. If final action is later identified, the FAA might consider further rulemaking then.

    Justification for Immediate Adoption and Determination of the Effective Date

    Section 553(b) of the Administrative Procedure Act (APA) (5 U.S.C. 551 et seq.) authorizes agencies to dispense with notice and comment procedures for rules when the agency, for “good cause,” finds that those procedures are “impracticable, unnecessary, or contrary to the public interest.” Under this section, an agency, upon finding good cause, may issue a final rule without providing notice and seeking comment prior to issuance. Further, section 553(d) of the APA authorizes agencies to make rules effective in less than thirty days, upon a finding of good cause.

    An unsafe condition exists that requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. The FAA has found that the risk to the flying public justifies forgoing notice and comment prior to adoption of this rule because the existing maintenance program may not be sufficient to detect a crack before it reaches a critical length since it could occur in an area covered by the external doubler. Such cracks in the wing rear spar lower caps and lower aft skin are not capable of sustaining a limit load event. This unsafe condition, if not addressed, could lead to reduced structural integrity of the airplane and loss of control of the airplane, which could result in a catastrophic event. Accordingly, notice and opportunity for prior public comment are impracticable and contrary to the public interest pursuant to 5 U.S.C. 553(b).

    The compliance time in this AD is shorter than the time necessary for the public to comment and for publication of the final rule. In addition, the FAA finds that good cause exists pursuant to 5 U.S.C. 553(d) for making this amendment effective in less than 30 days, for the same reasons the FAA found good cause to forgo notice and comment.

    Regulatory Flexibility Act

    The requirements of the Regulatory Flexibility Act (RFA) do not apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt a rule without prior notice and comment. Because the FAA has determined that it has good cause to adopt this rule without notice and comment, RFA analysis is not required.

    Costs of Compliance

    The FAA estimates that this AD affects 118 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD:

    Estimated Costs

    Action Labor cost Parts cost Cost per product Cost on U.S. operators
    Repetitive Inspections 27 work-hours × $85 per hour = $2,295 per inspection cycle $0 $2,295 per inspection cycle $270,810 per inspection cycle.

    On-Condition Costs

    Action Labor cost Parts cost Cost per product
    Reporting 1 work-hour × $85 per hour = $85 per inspection cycle $0 $85 per inspection cycle.