2024-04955. Airworthiness Directives; Airbus Canada Limited Partnership (Type Certificate Previously Held by C Series Aircraft Limited Partnership (CSALP); Bombardier, Inc.) Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede Airworthiness Directive (AD) 2021–09–03, which applies to certain Airbus Canada Limited Partnership Model BD–500–1A10 and BD–500–1A11 airplanes. AD 2021–09–03 requires repetitive replacements of the emergency locator transmitter (ELT) antenna and repetitive inspections of the exterior fuselage skin around the ELT antenna attachment area. Since the FAA issued AD 2021–09–03, it has been reported that there was an in-service failure of an ELT antenna that occurred before the repetitive replacement interval required by AD 2021–09–03, and that a terminating action was developed. This proposed AD would continue to require the actions in AD 2021–09–03 and would require replacement of the ELT antenna with a new ELT antenna, inspection of the exterior fuselage skin around the ELT antenna attachment holes, and repair if necessary, as specified in a Transport Canada AD, which is proposed for incorporation by reference (IBR). 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 25, 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: [phone].

• 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–2024–0464; 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 the Transport Canada AD identified in this NPRM, contact Transport Canada, Transport Canada National Aircraft Certification, 159 Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada; telephone [phone]; email [e-mail]; website tc.canada.ca/en/aviation. It is also available at regulations.gov under Docket No. FAA–2024–0464.

• 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.

FOR FURTHER INFORMATION CONTACT:

Yaser Osman, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: [phone]; email: [e-mail].

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–2024–0464; Project Identifier MCAI–2022–01556–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 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 Yaser Osman, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: [phone]; email: [e-mail]. 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 2021–09–03, Amendment 39–21516 (86 FR 20266, April 19, 2021); corrected April 27, 2021 (86 FR 22111) (AD 2021–09–03), for certain Airbus Canada Limited Partnership Model BD–500–1A10 and BD–500–1A11 airplanes. AD 2021–09–03 was prompted by an MCAI originated by Transport Canada, which is the aviation authority for Canada. Transport Canada issued AD CF–2021–10, dated March 18, 2021 (Transport Canada AD CF–2021–10), to correct an unsafe condition.

AD 2021–09–03 requires repetitive replacements of the ELT antenna with a new ELT antenna and repetitive inspections for damage of the exterior fuselage skin around the ELT antenna attachment area. The FAA issued AD 2021–09–03 to address ELT antenna failure, which can lead to the loss of the ELT antenna and the development of fuselage cracks that can result in an inability to maintain cabin pressure.

Actions Since AD 2021–09–03 Was Issued

Since the FAA issued AD 2021–09–03, Transport Canada superseded Transport Canada AD CF–2021–10 and issued Transport Canada AD CF–2022–67, dated December 6, 2022 (Transport Canada AD CF–2022–67) (also referred to as the MCAI), to correct an unsafe condition for certain Airbus Canada Limited Partnership Model BD–500–1A10 and BD–500–1A11 airplanes. The MCAI states that since Transport Canada AD CF–2021–10 was issued, an aluminum ELT antenna has been made available to prevent ELT antenna failures resulting from vibration loads induced by air vortices shed by the Gogo 2Ku antenna radome. In addition, there was an in-service failure of an ELT antenna that occurred before the repetitive replacement interval required by Transport Canada AD CF–2021–10 was reached. The MCAI also states installation of the aluminum ELT antenna terminates the requirements of Transport Canada CF–2022–67, and that the applicability has been limited to airplanes on which the aluminum ELT antenna has not been installed in production.

The FAA is proposing this AD to address ELT antenna failure, which can lead to the loss of the ELT antenna and the development of fuselage cracks that can result in an inability to maintain cabin pressure. You may examine the MCAI in the AD docket at regulations.gov under Docket No. FAA–2024–0464.

Explanation of Retained Requirements

Although this proposed AD does not explicitly restate the requirements of AD 2021–09–03, this proposed AD would retain all of the requirements of AD 2021–09–03. Those requirements are referenced in Transport Canada AD CF–2022–67, which, in turn, is referenced in paragraph (g) of this proposed AD.

Related Service Information Under 1 CFR Part 51

Transport Canada AD CF–2022–67 specifies procedures for:

• Repetitive replacements of the ELT antenna with a new ELT antenna and repetitive inspections for damage (including cracking) of the exterior fuselage skin around the ELT antenna attachment area, and
• A one-time replacement of the ELT antenna with a new aluminum ELT antenna, and detailed inspection for damage (including cracking) of the exterior fuselage skin around the ELT antenna attachment holes, and repair of any damage, which terminate the repetitive replacements and inspections.

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 referenced above. The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop in other products of the same type design.

Proposed AD Requirements in This NPRM

This proposed AD would require accomplishing the actions specified in Transport Canada AD CF–2022–67 described previously, except for any differences identified as exceptions in the regulatory text of this proposed AD.

Explanation of Required Compliance Information

In the FAA's ongoing efforts to improve the efficiency of the AD process, the FAA developed a process to use some civil aviation authority (CAA) ADs as the primary source of information for compliance with requirements for corresponding FAA ADs. The FAA has been coordinating this process with manufacturers and CAAs. As a result, the FAA proposes to incorporate Transport Canada AD CF–2022–67 by reference in the FAA final rule. This proposed AD would, therefore, require compliance with Transport Canada AD CF–2022–67 in its entirety through that incorporation, except for any differences identified as exceptions in the regulatory text of this proposed AD. Service information required by Transport Canada AD CF–2022–67 for compliance will be available at regulations.gov under Docket No. FAA–2024–0464 after the FAA final rule is published.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would affect 56 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD:

Estimated Costs for Required Actions

Action	Labor cost	Parts cost	Cost per product	Cost on U.S. operators
Retained actions from AD 2021–09–03	4 work-hours × $85 per hour = $340	$4,230	$4,570	$255,920
New proposed actions	4 work-hours × $85 per hour = $340	5,561	5,901	330,456

The FAA estimates the following costs to do any necessary on-condition actions that would be required based on the results of any required actions. The FAA has no way of determining the number of aircraft that might need these on-condition actions:

Estimated Costs of On-Condition Actions

Labor cost	Parts cost	Cost per product
4 work-hours × $85 per hour = $340	$2,000	$2,340

According to the manufacturer, some or all of the costs of this proposed AD may be covered under warranty, thereby reducing the cost impact on affected individuals. The FAA does not control warranty coverage for affected individuals. As a result, the FAA has included all known costs in the cost estimate.

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

[Amended]

2. The FAA amends § 39.13 by:

a. Removing Airworthiness Directive (AD) 2021–09–03, Amendment 39–21516 ( 86 FR 20266, April 19, 2021); corrected April 27, 2021 (86 FR 22111); and

b. Adding the following new AD:

Airbus Canada Limited Partnership (Type Certificate Previously Held by C Series Aircraft Limited Partnership (CSALP); Bombardier, Inc.): Docket No. FAA–2024–0464; Project Identifier MCAI–2022–01556–T.

(a) Comments Due Date

The FAA must receive comments on this airworthiness directive (AD) by April 25, 2024.

(b) Affected ADs

This AD replaces AD 2021–09–03, Amendment 39–21516 (86 FR 20266, April 19, 2021); corrected April 27, 2021 (86 FR 22111) (AD 2021–09–03).

(c) Applicability

This AD applies to Airbus Canada Limited Partnership Model BD–500–1A10 and BD–500–1A11 airplanes, certificated in any category, as identified in Transport Canada AD CF–2022–67, dated December 6, 2022 (Transport Canada AD CF–2022–67).

(d) Subject

Air Transport Association (ATA) of America Code 25, Equipment/furnishings; 53, Fuselage.

(e) Unsafe Condition

This AD was prompted by reports of the failure of emergency locator transmitter (ELT) antennas, including an in-service failure that occurred before the repetitive replacement interval required by AD 2021–09–03, and by the development of a terminating action. The FAA is issuing this AD to address ELT antenna failure. The unsafe condition, if not addressed, could result in loss of the ELT antenna and the development of fuselage cracks that can result in an inability to maintain cabin pressure.

(f) Compliance

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

(g) Requirements

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–2022–67.

(h) Exception to Transport Canada AD CF–2022–67

(1) Where Transport Canada AD CF–2022–67 refers to its effective date, this AD requires using the effective date of this AD.

(2) Where Transport Canada AD CF–2022–67 refers to April 1, 2021 (the effective date of Transport Canada AD CF–2021–10, dated March 18, 2021), this AD requires using May 4, 2021 (the effective date of AD 2021–09–03).

(3) Where Transport Canada AD CF–2022–67 refers to hours air time, this AD requires using flight hours.

(4) Where paragraph C. of Transport Canada AD CF–2022–67 specifies to “replace the ELT antenna with a new aluminum ELT antenna and inspect the exterior fuselage skin around the ELT antenna attachment holes for damage, repairing any damage found before further flight,” this AD requires replacing that text with “replace the ELT antenna with a new aluminum ELT antenna, including doing an inspection of the exterior fuselage skin around the ELT antenna attachment holes for damage, and, before further flight, repair any damage found.”

(i) Additional AD Provisions

The following provisions also apply to this AD:

(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: [e-mail].

(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 2021–09–03 are not approved as AMOCs for the corresponding provisions of Transport Canada AD CF–2022–67 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 Airbus Canada Limited Partnership'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 Yaser Osman, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: [phone]; email: [e-mail].

(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) Transport Canada AD CF–2022–67, dated December 6, 2022.

(ii) [Reserved]

(3) For Transport Canada AD CF–2022–67, contact Transport Canada, Transport Canada National Aircraft Certification, 159 Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada; telephone [phone]; email [e-mail]; website tc.canada.ca/en/aviation.

(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 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 [e-mail].

Issued on March 4, 2024.

Victor Wicklund,

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