DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2023-1654; Project Identifier MCAI-2023-00920-T;
Amendment 39-22520; AD 2023-16-01]
Airworthiness Directives; Bombardier, Inc., Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2023-12-
20, which applied to certain Bombardier, Inc., Model CL-600-2B16 (604
Variant) airplanes. AD 2023-12-20 required replacing certain oxygen
system hoses and prohibited installing affected oxygen hoses. Since the
FAA issued AD 2023-12-20, the FAA has learned of an error in a required
compliance time. This AD retains the requirements of AD 2023-12-20,
with a revised compliance time for the replacement. The FAA is issuing
this AD to address the unsafe condition on these products.
DATES: This AD is effective August 23, 2023.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of August 23,
2023 (88 FR 46063, July 19, 2023).
The FAA must receive comments on this AD by September 21, 2023.
ADDRESSES: You may send comments, using the procedures found in
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-2023-1654; 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, 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 service information identified in this final rule,
contact Bombardier Business Aircraft Customer Response Center, 400
Cote-Vertu Road West, Dorval, Quebec H4S 1Y9, Canada;
telephone 514-855-2999; email email@example.com; website
You may view this referenced 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. It is also available at
regulations.gov under Docket No. FAA-2023-1654.
FOR FURTHER INFORMATION CONTACT: Elizabeth Dowling, Aviation Safety
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
telephone 516-228-7300; email firstname.lastname@example.org.
The FAA invites you to send any written data, views, or arguments
about this final rule. Send your comments to an address listed under
ADDRESSES. Include ``Docket No. FAA-2023-1654; Project Identifier MCAI-
2023-00920-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
Elizabeth Dowling, Aviation Safety Engineer, FAA, 1600 Stewart Avenue,
Suite 410, Westbury, NY 11590; telephone 516-228-7300; email
email@example.com. Any commentary that the FAA receives which is
specifically designated as CBI will be placed in the public docket for
The FAA issued AD 2023-12-20, Amendment 39-22479 (88 FR 46063, July
19, 2023) (AD 2023-12-20), for certain Bombardier, Inc., Model CL-600-
2B16 (604 Variant) airplanes. AD 2023-12-20 was prompted by an MCAI
originated by Transport Canada, which is the aviation authority for
Canada. Transport Canada issued AD CF-2022-34, dated June 20, 2022
(Transport Canada AD CF-2022-34), to correct an unsafe condition.
AD 2023-12-20 required replacing oxygen system hoses having any
part number in the O2C20T1 and O2C20T14 series and prohibited
installing affected oxygen hoses. The FAA issued AD 2023-12-20 to
address a leak in the oxygen system, which could result in failure to
provide oxygen to passengers and crew and result in an oxygen-
enriched atmosphere creating a fire risk on the airplane.
Actions Since AD 2023-12-20 Was Issued
Since AD 2023-12-20 was issued, the FAA has learned that paragraph
(g)(1) of AD 2023-12-20 contains an error in the compliance time for
the replacement of the oxygen system hoses. As written, paragraph
(g)(1) of AD 2023-12-20 requires compliance for the affected airplanes
within 31 months, or no later than ``12 months after the completion of
the interior modification specified in STC ST02355NY,'' whichever
occurs first. The correct compliance time is within 31 months, or no
later than ``12 months after the airplane reaches 6 years from the STC
ST02355NY airplane's completion issuance (specific airplane's
Modification Data Summary release date),'' whichever occurs first.
Paragraph (g)(1) of this AD specifies the correct compliance time. The
compliance time as written in AD 2023-12-20 could unnecessarily ground
some airplanes. Correcting this error in this AD provides relief by
extending the compliance time. There are no other changes in this AD.
While the two ADs are effective August 23, 2023, this AD supersedes
The FAA is issuing this AD to address the unsafe condition on these
You may examine the MCAI in the AD docket at regulations.gov under
Docket No. FAA-2023-1654.
Related Service Information Under 1 CFR Part 51
This AD requires Bombardier Service Bulletins 605-35-006 and 650-
35-002, both Revision 01, both dated January 28, 2022, which the
Director of the Federal Register approved for incorporation by
reference as of August 23, 2023 (88 FR 46063, July 19, 2023). 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 ADDRESSES.
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 referenced above. The FAA is issuing this AD after
determining that the unsafe condition described previously is likely to
exist or develop on other products of the same type design.
This AD retains all of the requirements of AD 2023-12-20, with a
revised compliance time for replacing the oxygen system hoses for
Justification for Immediate Adoption and Determination of the Effective
Section 553(b)(3)(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.
The FAA has learned of an error in a compliance time that could
unnecessarily ground some airplanes. Correcting this error provides
relief by extending that compliance time, and is the only change in
this AD. To address this issue in a timely manner, the FAA has
determined that it is appropriate to require the immediate adoption of
this AD without providing an opportunity for public comments prior to
adoption. Accordingly, notice and opportunity for prior public comment
are unnecessary pursuant to 5 U.S.C. 553(b)(3)(B).
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
Regulatory Flexibility Act (RFA)
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 FAA has determined
that it has good cause to adopt this rule without prior notice and
comment, RFA analysis is not required.
Costs of Compliance
The FAA estimates that this AD affects 42 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:
Estimated Costs for Retained Required Actions
|3 work-hours x $85 per hour =
Estimated Costs for Retained Optional
|1 work-hour x $85 per hour =
The FAA estimates the following costs
to do any necessary on-
condition actions that would be required based on the results of any
optional mitigating actions. The FAA has no way of determining the
number of aircraft that might need this on-condition action:
Estimated Costs of Retained On-Condition Actions
|3 work-hours x $85 per hour =
The FAA has included all known costs
in its cost estimate.
According to the manufacturer, however, some or all of the costs of
this 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.
This AD will not have federalism implications under Executive Order
13132. This AD will 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 that this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866, and
(2) Will not affect intrastate aviation in Alaska.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 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.
Sec. 39.13 [Amended]
2. The FAA amends Sec. 39.13 by:
a. Removing Airworthiness Directive 2023-12-20, Amendment 39-22479 (88
FR 46063, July 19, 2023); and
b. Adding the following new airworthiness directive: