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 Department of Transportation Federal Aviation Administration 14 CFR Part 39
[Docket No. FAA-2024-2420; Project Identifier MCAI-2024-00143-T]
RIN 2120-AA64
 AGENCY: Federal Aviation Administration (FAA), DOT.
 ACTION: Notice of proposed rulemaking (NPRM).
 SUMMARY: The FAA proposes to supersede Airworthiness Directive (AD) 2022-01-02, which applies to certain De Havilland Aircraft of Canada Limited Model DHC-8-400, -401, and -402 airplanes. AD 2022-01-02 requires inspecting for corrosion of the nacelle to wing rear spar attachment pins, and the nacelle to landing gear attachment pins, and doing all applicable corrective actions. Since the FAA issued AD 2022-01-02, it was discovered that some operators were unable to identify the airplanes subject to each requirement. This proposed AD would continue to require the actions specified in AD 2022-01-02, clarify the affected airplanes for each required action, and revise the applicability by removing Model DHC-8-400 airplanes, as specified in a Transport Canada AD, which is proposed for incorporation by reference (IBR). This proposed AD would also revise a certain compliance time. 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 December 27, 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-2024-2420; 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 Transport Canada material identified in this proposed AD, contact Transport Canada, Transport Canada National Aircraft Certification, 159 Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada; telephone 888-663-3639; email*TC.AirworthinessDirectives-Consignesdenavigabilite.TC@tc.gc.ca*; website at 
                        *tc.canada.ca/en/aviation.*
                    You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For( print page 88911)
                        information on the availability of this material at the FAA, call 206-231-3195.
 FOR FURTHER INFORMATION CONTACT: Fatin Saumik, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7300; email 
                        *9-avs-nyaco-cos@faa.gov.*


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-2024-2420; Project Identifier MCAI-2024-00143-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 Fatin Saumik, Aviation Safety Engineer, FAA, 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 The FAA issued AD 2022-01-02, Amendment 39-21890 (87 FR 4145, January 27, 2022) (AD 2022-01-02), for certain De Havilland Aircraft of Canada Limited Model DHC-8-400, -401, and -402 airplanes. AD 2022-01-02 was prompted by MCAI originated by Transport Canada, which is the aviation authority for Canada. Transport Canada issued AD CF-2020-51R1, dated February 24, 2021 (Transport Canada AD CF-2020-51R1), to correct an unsafe condition. AD 2022-01-02 requires doing a detailed visual inspection of the nacelle to wing rear spar attachment pins, and the nacelle to landing gear attachment pins, for any corrosion, and doing all applicable corrective actions. The FAA issued AD 2022-01-02 to address premature corrosion and subsequent failure of the nacelle to landing gear and nacelle to rear wing spar attachment pins, which, if undetected, could lead to a single or dual collapse of the main landing gear. Actions Since AD 2022-01-02 Was Issued Since the FAA issued AD 2022-01-02, Transport Canada superseded AD CF-2020-51R1, dated February 24, 2021. Transport Canada AD CF-2020-51R2, dated February 27, 2024 (Transport Canada AD CF-2020-51R2) (referred to after this as the MCAI), was issued to correct an unsafe condition on certain De Havilland Aircraft of Canada Limited Model DHC-8-401 and -402 airplanes. The MCAI provides clarification of the applicability for each of its parts (Parts I through V) and otherwise maintains the requirements of AD CF-2020-51R1. It also revises the applicability section to remove Model DHC-8-400 airplanes since no model DHC-8-400 airplanes have been delivered. In addition, the FAA discovered an error in AD 2022-01-02, which included a compliance time that incorrectly used the number of flight cycles on the airplane instead of on the pins. The FAA is proposing this AD to address premature corrosion and subsequent failure of the nacelle to landing gear and nacelle to rear wing spar attachment pins, which, if undetected, could lead to a single or dual collapse of the main landing gear. You may examine the MCAI in the AD docket at 
                    *regulations.gov*
                     under Docket No. FAA-2024-2420. Explanation of Retained Requirements Although this proposed AD does not explicitly restate the requirements of AD 2022-01-02, this proposed AD would retain all of the requirements of AD 2022-01-02. Those requirements are referenced in Transport Canada AD CF-2020-51R2, which, in turn, is referenced in paragraph (g) of this proposed AD. Related Material Under 1 CFR Part 51 Transport Canada AD CF-2020-51R2 specifies procedures for doing a detailed visual inspection of the nacelle to wing rear spar attachment pins, and the nacelle to landing gear attachment pins, for any corrosion; and doing all applicable corrective actions. Corrective actions include applying epoxy primer to the bore surface of the pins, performing a fluorescent magnetic particle inspection for any cracking, removing corrosion, reworking and part marking certain pins, and replacing any cracked or corroded pins with serviceable pins. 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. 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 material referenced 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 retain all requirements of AD 2022-01-02 and clarify the airplanes subject to each requirement. This proposed AD would remove Model DHC-8-400 airplanes from the applicability and revise a certain compliance time as specified in an exception in paragraph (h)(2) of this proposed AD. Costs of Compliance The FAA estimates that this AD, if adopted as proposed, would affect 41 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD:
                    ( print page 88912) Estimated Costs for Required Actions
Labor cost
Parts cost
Cost per product
Cost on U.S. operatorsUp to 25 work-hours × $85 per hour = Up to $2,125
Up to $21
Up to $2,146
Up to $87,986.
 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. List of Subjects in 14 CFR Part 39 Air transportation
Aircraft
Aviation safety
Incorporation by reference
Safety
 The Proposed Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows: PART 39—AIRWORTHINESS DIRECTIVES
 1.The authority citation for part 39 continues to read as follows: Authority:
                    49 U.S.C. 106(g), 40113, 44701. § 39.13
 2.The FAA amends § 39.13 by: a.Removing Airworthiness Directive (AD) 2022-01-02, Amendment 39-21890 ( 87 FR 4145, January 27, 2022); and b.Adding the following new AD: **De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.):**
                         Docket No. FAA-2024-2420; Project Identifier MCAI-2024-00143-T. (a) Comments Due Date The FAA must receive comments on this airworthiness directive (AD) by December 27, 2024. (b) Affected ADs This AD replaces AD 2022-01-02, Amendment 39-21890 (87 FR 4145, January 27, 2022) (AD 2022-01-02). (c) Applicability This AD applies to De Havilland Aircraft of Canada Limited (type certificate previously held by Bombardier, Inc.) Model DHC-8-401 and -402 airplanes, certificated in any category, as identified in Transport Canada AD CF-2020-51R2, dated February 27, 2024 (Transport Canada AD CF-2020-51R2). (d) Subject Air Transport Association (ATA) of America Code 54, Nacelles/pylons. (e) Unsafe Condition This AD was prompted by a report that the epoxy primer on the internal bore of the nacelle and landing gear attachment pins was not applied, and corrosion on the internal bore of the wing rear spar attachment pins was found. The FAA is issuing this AD to address premature corrosion and subsequent failure of the nacelle to landing gear and nacelle to rear wing spar attachment pins. The unsafe condition, if not addressed, could result a single or dual collapse of the main landing gear. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions Except as specified in paragraph (h) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, Transport Canada AD CF-2020-51R2. (h) Exceptions to Transport Canada AD 2022-01-02 (1) Where Transport Canada AD 2022-01-02 refers to “the effective date of CF-2020-51, 9 December 2020,” this AD requires using March 3, 2022 (the effective date of AD 2022-01-02). (2) Where paragraph A. of Parts I, II, and III, and Parts IV and V, of Transport Canada AD CF-2020-51R2 specify the compliance time, for this AD, the compliance time for paragraph A. of Parts I, II, and III, and for Parts IV and V, of Transport Canada AD CF-2020-51R2 is at the later of the times in paragraphs (h)(2)(i) and (ii) of this AD. (i) Prior to the pins reaching 14 years from their entry-into-service or prior to the pins reaching 30,000 total flight cycles, whichever occurs first. (ii) Within 30 days after the effective date of this AD. (i) Additional AD Provisions (1) 
                        *Alternative Methods of Compliance (AMOCs):*
                         The Manager, International Validation 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 International Validation Branch, mail it to the address identified in paragraph (j) of this AD. Information may be emailed to 
                        *AMOC@faa.gov.* (i) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office. (ii) AMOCs approved previously for AD 2022-01-02 are approved as AMOCs for the corresponding provisions of Transport Canada AD CF-2020-51R2 that are required by paragraph (g) of this AD. (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, International Validation Branch, FAA; or Transport Canada; or De Havilland Aircraft of Canada Limited's Transport Canada Design Approval Organization (DAO). If approved by the DAO, the approval must include the DAO-authorized signature. (j) Additional Information For more information about this AD, contact Fatin Saumik, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7300; email 
                        *9-avs-nyaco-cos@faa.gov.*( print page 88913) (k) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference (IBR) of the material listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this material as applicable to do the actions required by this AD, unless this AD specifies otherwise. (i) Transport Canada AD CF-2020-51R2, dated February 27, 2024. (ii) [Reserved] (3) For Transport Canada material identified in this AD, contact Transport Canada, Transport Canada National Aircraft Certification, 159 Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada; telephone 888-663-3639; email 
                        *TC.AirworthinessDirectives-Consignesdenavigabilite.TC@tc.gc.ca;*
                         website 
                        *tc.canada.ca/en/aviation.* (4) 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. (5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit 
                        *www.archives.gov/​federal-register/​cfr/​ibr-locations*
                         or email 
                        *fr.inspection@nara.gov*. Issued on November 4, 2024. Victor Wicklund, Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.


[FR Doc. 2024-25982 Filed 11-8-24; 8:45 am] BILLING CODE 4910-13-P