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[Federal Register Volume 90, Number 29 (Thursday, February 13, 2025)]
[Proposed Rules]
[Pages 9526-9529]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-02505]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2025-0199; Project Identifier MCAI-2024-00332-T]
RIN 2120-AA64

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).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain Airbus Canada Limited Partnership Model BD-500-1A10 and BD-
500-1A11 airplanes. This proposed AD was prompted by certification 
testing that found that environmental control system (ECS) ducts 
manufactured using a certain material failed the flammability test 
requirements established for compliance. This proposed AD would require 
inspecting the affected ECS ducts and, as applicable, installing a 
fire-resistant sleeve assembly over any non-compliant ECS duct, and 
prohibit the installation of ECS ducts as replacement parts under 
certain conditions, 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 March 31, 
2025.

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

[[Page 9527]]

p.m., Monday through Friday, except Federal holidays.
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2025-0199; 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 [email protected]; website tc.canada.ca/en/aviation. 
It is also available at regulations.gov under Docket No. FAA-2025-0199.
     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: Brenda Buitrago Perez, Aviation Safety 
Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone 
516-228-7368; email [email protected].

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-2025-0199; 
Project Identifier MCAI-2024-00332-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 
Brenda Buitrago Perez, Aviation Safety Engineer, FAA, 2200 South 216th 
St., Des Moines, WA 98198; telephone 516-228-7368; email 
[email protected]. Any commentary that the FAA receives 
that 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-2024-21, dated June 20, 2024 (Transport 
Canada AD CF-2024-21) (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 ECS ducts, 
located on forward and aft cargo compartment ceiling panels, having 
part numbers (P/Ns) D761189-105, D761189-501, and D762232-509, have 
been manufactured using material APF1180-7781, which replaced 
discontinued legacy material Solvay L591PG-7781. The material change to 
APF1180-7781 was done without changing the ECS duct part number. 
Subsequent certification testing of the ECS ducts made using material 
APF1180-7781 failed flammability test requirements. These noncompliant 
ECS ducts may have been installed on certain affected airplanes during 
production. Noncompliant ECS ducts could result in the inability to 
contain a fire within the cargo compartment, which could result in an 
uncontrolled fire.
    The FAA is proposing this AD to address the unsafe condition on 
these products.
    You may examine the MCAI in the AD docket at regulations.gov under 
Docket No. FAA-2025-0199.

Material Incorporated by Reference Under 1 CFR Part 51

    Transport Canada AD CF-2024-21 specifies procedures for inspecting 
to determine the lot numbers of affected ECS ducts and installing a 
fire-resistant sleeve assembly over any non-compliant ECS duct. 
Transport Canada AD CF-2024-21 also prohibits the installation of ECS 
ducts as replacement parts under certain conditions. 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-2024-21 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-2024-21 by reference 
in the FAA final rule. This proposed AD would, therefore, require 
compliance with Transport Canada AD CF-2024-21 in its entirety through 
that incorporation, except for any differences identified as exceptions 
in the regulatory text of this proposed AD. Material required by 
Transport Canada AD CF-2024-21 for compliance will be available at 
regulations.gov under Docket No. FAA-2025-0199 after the FAA final rule 
is published.

[[Page 9528]]

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 11 airplanes of U.S. registry. The FAA estimates the following 
costs to comply with this proposed AD:

                                      Estimated Costs for Required Actions
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                                                                                    Cost per       Cost on U.S.
                          Labor cost                              Parts cost        product         operators
----------------------------------------------------------------------------------------------------------------
12 work-hours x $85 per hour = $1,020........................              $0           $1,020          $11,220
----------------------------------------------------------------------------------------------------------------

    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
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2 work-hours x $85 per hour = $170             (*)               * $170
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* The FAA has received no definitive data on which to base the cost
  estimates for the parts cost specified in this proposed AD.

    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some or all of the costs of 
this proposed AD may be covered under warranty, thereby reducing the 
cost impact on affected operators.

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

0
1. The authority citation for part 39 continues to read as follows:

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

Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

Airbus Canada Limited Partnership (Type Certificate Previously Held 
by C Series Aircraft Limited Partnership (CSALP); Bombardier, Inc.): 
Docket No. FAA-2025-0199; Project Identifier MCAI-2024-00332-T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by March 31, 2025.

(b) Affected ADs

    None.

(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-2024-21, dated June 20, 2024 
(Transport Canada AD CF-2024-21).

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by certification testing that found that 
environmental control system (ECS) ducts manufactured using material 
APF1180-7781 failed the flammability test requirements established 
for compliance. The FAA is issuing this AD to address noncompliant 
ECS ducts that could cause an inability to contain a fire within the 
cargo compartment. The unsafe condition, if not addressed, could 
result in an uncontrolled fire.

(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-2024-21.

(h) Exception to Transport Canada AD CF-2024-21

    (1) Where Transport Canada AD CF-2024-21 refers to its effective 
date, this AD requires using the effective date of this AD.
    (2) Where Transport Canada AD CF-2024-21 refers to hours air 
time, this AD requires using flight hours.

[[Page 9529]]

(i) Additional AD Provisions

    The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, AIR-
520, Continued Operational Safety 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 Continued Operational Safety Branch, send it to the attention of 
the person identified in paragraph (j) of this AD and email to: 
[email protected]. 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, AIR-520, 
Continued Operational Safety 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.
    (3) Required for Compliance (RC): Except as required by 
paragraph (i)(2) of this AD, if any material contains procedures or 
tests that are identified as RC, those procedures and tests must be 
done to comply with this AD; any procedures or tests that are not 
identified as RC are recommended. Those procedures and tests that 
are not identified as RC may be deviated from using accepted methods 
in accordance with the operator's maintenance or inspection program 
without obtaining approval of an AMOC, provided the procedures and 
tests identified as RC can be done and the airplane can be put back 
in an airworthy condition. Any substitutions or changes to 
procedures or tests identified as RC require approval of an AMOC.

(j) Additional Information

    For more information about this AD, contact Brenda Buitrago 
Perez, Aviation Safety Engineer, FAA, 2200 South 216th St., Des 
Moines, WA 98198; telephone 516-228-7368; email 
[email protected].

(k) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference 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-2024-21, dated June 20, 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 [email protected]; 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 [email protected].

    Issued on February 6, 2025.
John P. Piccola, Jr.,
Director, Integrated Certificate Management Division, Aircraft 
Certification Service.
[FR Doc. 2025-02505 Filed 2-12-25; 8:45 am]
BILLING CODE 4910-13-P
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