2023-03636. Airworthiness Directives; Bombardier, Inc., Airplanes  

  • Start Preamble

    AGENCY:

    Federal Aviation Administration (FAA), DOT.

    ACTION:

    Notice of proposed rulemaking (NPRM).

    SUMMARY:

    The FAA proposes to adopt a new airworthiness directive (AD) for certain Bombardier, Inc., Model BD-700-1A10, and BD-700-1A11 airplanes. This proposed AD was prompted by a determination that new or more restrictive airworthiness limitations are necessary. This proposed AD would require revising the existing maintenance or inspection program, as applicable, to incorporate more restrictive airworthiness limitations. The FAA is proposing this AD to address the unsafe condition on these products.

    DATES:

    The FAA must receive comments on this proposed AD by April 13, 2023.

    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-2023-0169; 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 NPRM, the mandatory continuing airworthiness information (MCAI), any comments received, and other information. The street address for Docket Operations is listed above.

    Material Incorporated by Reference:

    • For Bombardier service information identified in this NPRM, contact Bombardier Business Aircraft Customer Response Center, 400 Côte-Vertu Road West, Dorval, Québec H4S 1Y9, Canada; telephone 514-855-2999; email ac.yul@aero.bombardier.com; website bombardier.com.

    • You may view this service information 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.
    Start Further Info

    FOR FURTHER INFORMATION CONTACT:

    Gabriel Kim, Aerospace Engineer, Mechanical Systems and Administrative Services Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7300; email 9-avs-nyaco-cos@faa.gov.

    End Further Info End Preamble Start Supplemental Information

    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 ADDRESSES . Include “Docket No. FAA-2023-0169; Project Identifier MCAI-2022-00462-T” 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 amend the 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 Gabriel Kim, Aerospace Engineer, Mechanical Systems and Administrative Services Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7300; email 9-avs-nyaco-cos@faa.gov. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking.

    Background

    Transport Canada, which is the aviation authority for Canada, has issued Transport Canada AD CF-2022-15, dated April 7, 2022 (Transport Canada AD CF-2022-15) (also referred to after this as the MCAI), to correct an unsafe condition on certain Bombardier, Inc., Model BD-700-1A10, and BD-700-1A11 airplanes. The MCAI states that during a design review, it was discovered that three candidate certification maintenance requirements (CCMRs) which were dispositioned as maintenance review board report (MRBR) tasks had reached or exceeded the limit for escalation and that exceeding the CCMR limitations could result in unsafe conditions. The MCAI also states that Bombardier issued Start Printed Page 12277 certification maintenance requirements (CMRs) to prevent escalation and reduce the interval, as applicable, for these tasks, which consist of a functional test of the landing-gear emergency extension; an operational test of the brake shutoff valve; and a visual check of the passenger-door vent-flap mechanism.

    The FAA is proposing this AD to address the following unsafe conditions:

    • Dormant failure of the landing gear emergency extension system, which could lead to failure to extend the landing gear when normal gear extension has failed. This unsafe condition, if not addressed, could result in an annunciated failure to extend both main landing gears or all landing gears.
    • Dormant failure of the brake shut off valve in the open state. This unsafe condition, if not addressed, could result in uncommanded braking during take-off.
    • Dormant failure of the vent flap assembly where it fails in the closed position, which could result in the failure to prevent the initiation of cabin pressurization when the passenger door is not fully closed, latched and locked. This unsafe condition, if not addressed, could result in the passenger door opening under pressure on ground or during flight.

    You may examine the MCAI in the AD docket at regulations.gov under Docket No. FAA-2023-0169.

    Related Service Information Under 1 CFR Part 51

    The FAA reviewed the following airplane maintenance manual (AMM) tasks from Bombardier.

    • Tasks 32-34-00-101, “Functional Test of the Landing-Gear Emergency Extension;” 32-43-25-101, “Operational Test of the Brake Shutoff Valve;” and 52-11-00-106, “Visual Check of the Passenger-Door Vent-Flap Mechanism;” of Part 2, “Airworthiness Limitations,” of the Bombardier Global Express Time Limits/Maintenance Checks (TLMC), Publication No. BD-700 TLMC, Revision 34, dated March 1, 2022. (For obtaining the tasks for Bombardier Global Express TLMC, Publication No. BD-700 TLMC, use Document Identification No. GL 700 TLMC.)
    • Tasks 32-34-00-101, “Functional Test of the Landing-Gear Emergency Extension;” 32-43-25-101, “Operational Test of the Brake Shutoff Valve;” and 52-11-00-101, “Visual Check of the Passenger-Door Vent-Flap Mechanism;” of Part 2, “Airworthiness Limitations,” of the Bombardier Global Express XRS TLMC, Publication No. BD-700 XRS TLMC, Revision 21, dated March 1, 2022. (For obtaining the tasks for Bombardier Global Express XRS TLMC, Publication No. BD-700 XRS TLMC, use Document Identification No. GL XRS TLMC.)
    • Tasks 32-34-00-101, “Functional Test of the Landing-Gear Emergency Extension;” 32-43-25-101, “Operational Test of the Brake Shutoff Valve;” and 52-11-00-106, “Visual Check of the Passenger-Door Vent-Flap Mechanism;” of Part 2, “Airworthiness Limitations,” of the Bombardier Global 5000 TLMC, Publication No. BD-700 TLMC, Revision 25, dated March 1, 2022. (For obtaining the tasks for Bombardier Global 5000 TLMC, Publication No. BD-700 TLMC, use Document Identification No. GL 5000 TLMC.)
    • Tasks 32-34-00-101, “Functional Test of the Landing-Gear Emergency Extension;” 32-43-25-101, “Operational Test of the Brake Shutoff Valve;” and 52-11-00-106, “Visual Check of the Passenger-Door Vent-Flap Mechanism;” of Part 2, “Airworthiness Limitations,” of the Bombardier Global 5000 Featuring Global Vision Flight Deck (GVFD) TLMC, Publication No. GL 5000 GVFD TLMC, Revision 15, dated March 1, 2022. (For obtaining the tasks for Bombardier Global 5000 Featuring GVFD TLMC, Publication No. GL 5000 GVFD TLMC, use Document Identification No. GL 5000 GVFD TLMC.)
    • Tasks 32-34-00-101, “Functional Test of the Landing-Gear Emergency Extension;” 32-43-25-101, “Operational Test of the Brake Shutoff Valve;” and 52-11-00-106, “Visual Check of the Passenger-Door Vent-Flap Mechanism;” of Part 2, “Airworthiness Limitations,” of the Bombardier Global 6000 TLMC, Publication No. GL 6000 TLMC, Revision 15, dated March 1, 2022. (For obtaining the tasks for Bombardier Global 6000 TLMC, Publication No. GL 6000 TLMC, use Document Identification No. GL 6000 TLMC.)

    This service information specifies more restrictive airworthiness limitations for CMRs. These documents are distinct since they apply to different airplane models in different configurations.

    This service information 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.

    FAA's Determination

    This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to the FAA's bilateral agreement with this State of Design Authority, it has notified the FAA of the unsafe condition described in the MCAI and service information described above. The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design.

    Proposed AD Requirements in This NPRM

    This proposed AD would require revising the existing maintenance or inspection program as applicable to incorporate more restrictive airworthiness limitations.

    This proposed AD would require revisions to certain operator maintenance documents to include new actions ( e.g., inspections). Compliance with these actions is required by 14 CFR 91.403(c). For airplanes that have been previously modified, altered, or repaired in the areas addressed by this proposed AD, the operator may not be able to accomplish the actions described in the revisions. In this situation, to comply with 14 CFR 91.403(c), the operator must request approval for an alternative method of compliance according to paragraph (i)(1) of this proposed AD.

    Differences Between This NPRM and the MCAI

    Where Transport Canada AD CF-2022-15 references associated MRBRs tasks, Figure 1 to paragraph (g) of this proposed AD references AMM tasks instead. The FAA has determined that CCMRs cannot be mandated by the FAA. However, equivalent AMM tasks may be mandated in lieu of CCMRs.

    Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would affect 413 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD:

    The FAA has determined that revising the maintenance or inspection program takes an average of 90 work-hours per operator, although the agency recognizes that this number may vary from operator to operator. Since operators incorporate maintenance or inspection program changes for their affected fleet(s), the FAA has determined that a per-operator estimate is more accurate than a per-airplane estimate. Therefore, the agency estimates the average total cost per operator to be $7,650 (90 work-hours × $85 per work-hour). Start Printed Page 12278

    Authority for This Rulemaking

    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.

    Regulatory Findings

    The FAA determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 this proposed regulation:

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

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

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

    Start List of Subjects

    List of Subjects in 14 CFR Part 39

    • Air transportation
    • Aircraft
    • Aviation safety
    • Incorporation by reference
    • Safety
    End List of Subjects

    The Proposed Amendment

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

    Start Part

    PART 39—AIRWORTHINESS DIRECTIVES

    End Part Start Amendment Part

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

    End Amendment Part Start Authority

    Authority: 49 U.S.C. 106(g), 40113, 44701.

    End Authority
    [Amended]
    Start Amendment Part

    2. The FAA amends § 39.13 by adding the following new airworthiness directive:

    End Amendment Part

    Bombardier, Inc.: Docket No. FAA-2023-0169; Project Identifier MCAI-2022-00462-T.

    (a) Comments Due Date

    The FAA must receive comments on this airworthiness directive (AD) by April 13, 2023.

    (b) Affected ADs

    None.

    (c) Applicability

    This AD applies to Bombardier, Inc., Model BD-700-1A10 and BD-700-1A11 airplanes, certificated in any category, having serial numbers 9002 through 9860 inclusive, 9862 through 9871 inclusive, 9873 through 9879 inclusive, 60005, 60024, 60030, 60032, 60037, 60043, 60045, 60049, 60056, 60057, 60061 and 60068.

    (d) Subject

    Air Transport Association (ATA) of America Code 05, Time Limits/Maintenance Checks.

    (e) Unsafe Condition

    This AD was prompted by a determination that more restrictive airworthiness limitations are necessary. The FAA is issuing this AD to address the unsafe conditions identified in paragraphs (e)(1) through (3) of this AD.

    (1) Dormant failure of the landing gear emergency extension system, which could lead to failure to extend the landing gear when normal gear extension has failed. This unsafe condition, if not addressed, could result in an annunciated failure to extend both main landing gears or all landing gears.

    (2) Dormant failure of the brake shut off valve in the open state. This unsafe condition, if not addressed, could result in uncommanded braking during take-off.

    (3) Dormant failure of the vent flap assembly where it fails in the closed position, which could result in the failure to prevent the initiation of cabin pressurization when the passenger door is not fully closed, latched and locked. This unsafe condition, if not addressed, could result in the passenger door opening under pressure on ground or during flight.

    (f) Compliance

    Comply with this AD within the compliance times specified, unless already done.

    (g) Maintenance or Inspection Program Revision

    Within 30 days from the effective date of this AD, revise the existing maintenance or inspection program, as applicable, to incorporate the information specified in the certification maintenance requirements (CMR) tasks identified in Figure 1 to paragraph (g) of this AD of Part 2, “Airworthiness Limitations,” of the applicable Time Limits/Maintenance Checks (TLMC) manuals identified in Figure 2 to paragraph (g) of this AD. The initial compliance time for doing the tasks is at the applicable time specified in Figure 1 to paragraph (g) of this AD, or within 30 days after the effective date of this AD, whichever occurs later.

    Start Printed Page 12279

    Figure 1 to paragraph (g)— New CMR Tasks

    Start Printed Page 12280

    Figure 2 to paragraph (g)— Applicable TLMCs

    (h) No Alternative Actions or Intervals

    After the existing maintenance or inspection program has been revised as required by paragraph (g) of this AD, no alternative actions ( e.g., inspections) or intervals may be used unless the actions or intervals are approved as an alternative method of compliance (AMOC) in accordance with the procedures specified in paragraph (i)(1) of this AD.

    (i) Additional AD Provisions

    The following provisions also apply to this AD:

    (1) Alternative Methods of Compliance (AMOCs): The Manager, New York ACO Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or responsible Flight Standards Office, as appropriate. If sending information directly to the manager of the New York ACO Branch, mail it to ATTN: Program Manager, Continuing Operational Safety, at the address Start Printed Page 12281 identified in paragraph (j)(2) of this AD or email to: 9-avs-nyaco-cos@faa.gov. If mailing information, also submit information by email. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office.

    (2) Contacting the Manufacturer: For any requirement in this AD to obtain instructions from a manufacturer, the instructions must be accomplished using a method approved by the Manager, New York ACO Branch, FAA; or Transport Canada or Bombardier, Inc.'s Transport Canada Design Approval Organization (DAO). If approved by the DAO, the approval must include the DAO-authorized signature.

    (j) Additional Information

    (1) Refer to Transport Canada AD CF-2022-15, dated April 7, 2022, for related information. This Transport Canada AD may be found in the AD docket at regulations.gov under Docket No. FAA-2023-0169.

    (2) For more information about this AD, contact Gabriel Kim, Aerospace Engineer, Mechanical Systems and Administrative Services Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7300; email 9-avs-nyaco-cos@faa.gov.

    (k) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.

    (2) You must use this service information as applicable to do the actions required by this AD, unless this AD specifies otherwise.

    (i) Task 32-34-00-101, “Functional Test of the Landing-Gear Emergency Extension,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global Express Time Limit/Maintenance Check manual (TLMC), Publication No. BD-700 TLMC, Revision 34, dated March 1, 2022.

    Note 1 to paragraph (k)(2)(i): For obtaining the tasks specified in paragraphs (k)(2)(i) through (iii) of this AD for Bombardier Global Express TLMC, Publication No. BD-700 TLMC, Revision 34, dated March 1, 2022, use Document Identification No. GL 700 TLMC.

    (ii) Task 32-43-25-101, “Operational Test of the Brake Shutoff Valve,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global Express TLMC, Publication No. BD-700 TLMC, Revision 34, dated March 1, 2022.

    (iii) Task 52-11-00-106, “Visual Check of the Passenger-Door Vent-Flap Mechanism,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global Express TLMC, Publication No. BD-700 TLMC, Revision 34, dated March 1, 2022.

    (iv) Task 32-34-00-101, “Functional Test of the Landing-Gear Emergency Extension,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global Express XRS TLMC, Publication No. BD-700 XRS TLMC, Revision 21, dated March 1, 2022.

    Note 2 to paragraph (k)(2)(iv): For obtaining the tasks specified in paragraphs (k)(2)(iv) through (vi) of this AD for Bombardier Global Express XRS TLMC, Publication No. BD-700 XRS TLMC, use Document Identification No. GL XRS TLMC.

    (v) Task 32-43-25-101, “Operational Test of the Brake Shutoff Valve,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global Express XRS TLMC, Publication No. BD-700 XRS TLMC, Revision 21, dated March 1, 2022.

    (vi) Task 52-11-00-106, “Visual Check of the Passenger-Door Vent-Flap Mechanism,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global Express XRS TLMC, Publication No. BD-700 XRS TLMC, Revision 21, dated March 1, 2022.

    (vii) Task 32-34-00-101, “Functional Test of the Landing-Gear Emergency Extension,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global 5000 TLMC, Publication No. BD-700 TLMC, Revision 25, dated March 1, 2022.

    Note 3 to paragraph (k)(2)(vii): For obtaining the tasks specified in paragraphs (k)(2)(vii) through (ix) of this AD for Bombardier Global 5000 TLMC, Publication No. BD-700 TLMC, use Document Identification No. GL 5000 TLMC.

    (viii) Task 32-43-25-101, “Operational Test of the Brake Shutoff Valve,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global 5000 TLMC, Publication No. BD-700 TLMC, Revision 25, dated March 1, 2022.

    (ix) Task 52-11-00-106, “Visual Check of the Passenger-Door Vent-Flap Mechanism,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global 5000 TLMC, Publication No. BD-700 TLMC, Revision 25, dated March 1, 2022.

    (x) Task 32-34-00-101, “Functional Test of the Landing-Gear Emergency Extension,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global 5000 Featuring Global Vision Flight Deck (GVFD) TLMC, Publication No. GL 5000 GVFD TLMC, Revision 15, dated March 1, 2022.

    Note 4 to paragraph (k)(2)(x): For obtaining the tasks specified in paragraphs (k)(2)(x) through (xii) of this AD for Bombardier Global 5000 Featuring GVFD TLMC, Publication No. GL 5000 GVFD TLMC, use Document Identification No. GL 5000 GVFD TLMC.

    (xi) Task 32-43-25-101, “Operational Test of the Brake Shutoff Valve,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global 5000 Featuring GVFD TLMC, Publication No. GL 5000 GVFD TLMC, Revision 15, dated March 1, 2022.

    (xii) Task 52-11-00-106, “Visual Check of the Passenger-Door Vent-Flap Mechanism,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global 5000 Featuring GVFD, Publication No. GL 5000 GVFD TLMC, Revision 15, dated March 1, 2022.

    (xiii) Task 32-34-00-101, “Functional Test of the Landing-Gear Emergency Extension,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global 6000 TLMC, Publication No. GL 6000 TLMC, Revision 15, dated March 1, 2022.

    Note 5 to paragraph (k)(2)(xiii): For obtaining the tasks specified in paragraphs (xiii) through (xv) of this AD for Bombardier Global 6000 TLMC, Publication No. GL 6000 TLMC, use Document Identification No. GL 6000 TLMC.

    (xiv) Task 32-43-25-101, “Operational Test of the Brake Shutoff Valve,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global 6000 TLMC, Publication No. GL 6000 TLMC, Revision 15, dated March 1, 2022.

    (xv) Task 52-11-00-106, “Visual Check of the Passenger-Door Vent-Flap Mechanism,” of Part 2, “Airworthiness Limitations,” of the Bombardier Global 6000 TLMC, Publication No. GL 6000 TLMC, Revision 15, dated March 1, 2022.

    (3) For service information identified in this AD, contact Bombardier Business Aircraft Customer Response Center, 400 Côte-Vertu Road West, Dorval, Québec H4S 1Y9, Canada; telephone 514-855-2999; email ac.yul@aero.bombardier.com; website bombardier.com.

    (4) You may view this service information 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.

    (5) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, email fr.inspection@nara.gov, or go to: www.archives.gov/​federal-register/​cfr/​ibr-locations.html.

    Start Signature

    Issued on February 15, 2023.

    Christina Underwood,

    Acting Director, Compliance & Airworthiness Division, Aircraft Certification Service.

    End Signature End Supplemental Information

    [FR Doc. 2023-03636 Filed 2-24-23; 8:45 am]

    BILLING CODE 4910-13-P

Document Information

Published:
02/27/2023
Department:
Federal Aviation Administration
Entry Type:
Proposed Rule
Action:
Notice of proposed rulemaking (NPRM).
Document Number:
2023-03636
Dates:
The FAA must receive comments on this proposed AD by April 13, 2023.
Pages:
12276-12281 (6 pages)
Docket Numbers:
Docket No. FAA-2023-0169, Project Identifier MCAI-2022-00462-T
RINs:
2120-AA64: Airworthiness Directives
RIN Links:
https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives
Topics:
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety
PDF File:
2023-03636.pdf
CFR: (1)
14 CFR 39.13