DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-2139; Project Identifier MCAI-2023-00435-T;
Amendment 39-22713; AD 2024-06-08]
RIN 2120-AA64

Airworthiness Directives; Bombardier, Inc., Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Bombardier, Inc., Model BD-700-2A12 airplanes. This AD was
prompted by reports from the supplier that some overheat detection
sensing elements of the bleed air leak detection system were
manufactured with insufficient salt fill, which can result in an
inability to detect hot bleed air leaks. This AD requires maintenance
records verification, and if an affected part is installed, prohibits
the use of certain Master Minimum Equipment List (MMEL) items under
certain conditions by requiring revising the operator's existing
Minimum Equipment List (MEL). This AD also requires testing the
overheat detection sensing elements, marking each serviceable sensing
element with a witness mark, and replacing each nonserviceable part
with a serviceable part. This AD also prohibits the installation of
affected parts under certain conditions. The FAA is issuing this AD to
address the unsafe condition on these products.

DATES: This AD is effective June 5, 2024.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of June 5, 2024.

ADDRESSES:
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2023-2139; 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
address for Docket Operations is U.S. Department of Transportation,
Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200
New Jersey Avenue SE, Washington, DC 20590.
Material Incorporated by Reference:
For Bombardier 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: ac.yul@aero.bombardier.com;
website: bombardier.com.
For Liebherr-Aerospace Toulouse SAS service information
identified in this final rule, contact Liebherr-Aerospace Toulouse SAS,
408, Avenue des Etats-Unis--B.P.52010, 31016 Toulouse Cedex, France;
telephone +33 (0)5.61.35.28.28; fax +33 (0)5.61.35.29.29; email:
techpub.toulouse@liebherr.com; website: www.liebherr.aero.
You may view this service information at the FAA,
Airworthiness Products Section, Operational Safety Branch, 2200 South
216th Street, Des Moines, WA. For information on the availability of
this material at the FAA, call 206-231-3195. It is also available in
the AD docket at regulations.gov under Docket No. FAA-2023-2139.

FOR FURTHER INFORMATION CONTACT: Steven Dzierzynski, 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:

Background

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to certain Bombardier,
Inc., Model BD-700-2A12 airplanes. The NPRM published in the Federal
Register on November 8, 2023 (88 FR 77044). The NPRM was prompted by AD
CF-2023-18, dated March 9, 2023, issued by Transport Canada, which is
the aviation authority for Canada (Transport Canada AD CF-2023-18)
(also referred to as the MCAI). The MCAI states that Bombardier
received reports from the supplier of the overheat detection sensing
elements of a manufacturing quality escape. Some of the sensing
elements of the bleed air leak detection system were manufactured with
insufficient salt fill. This condition can result in an inability to
detect hot bleed air leaks, which can cause damage to surrounding
structures and systems and prevent continued safe flight and landing.
In the NPRM, the FAA proposed to require maintenance records
verification, and if an affected part is installed, prohibit the use of
certain MMEL items under certain conditions by requiring revising the
operator's existing MEL. The NPRM also proposed to require testing the
overheat detection sensing elements, marking each serviceable sensing
element with a witness mark, and replacing each nonserviceable part
with a serviceable part. The NPRM also proposed to prohibit the
installation of affected parts under certain conditions. The FAA is
issuing 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-2023-2139.

Discussion of Final Airworthiness Directive

Comments

The FAA received a comment from NetJets. The following presents the
comment received on the NPRM and the FAA's response to the comment.

Request for Clarification on Location of Date of Manufacture

NetJets requested a statement be added to paragraph (h) of the
proposed AD indicating that the date of manufacture can be found in the
aircraft maintenance logbook, in addition to the identification plate
of the airplane on certain airplanes. This information is stated in
Transport Canada AD CF-2023-18, Part II, paragraph A. NetJets further
stated that Bombardier no longer stamps a date on the airframe data
plate.
The FAA agrees the date of manufacture can be found either on the
identification plate of certain airplanes or in the aircraft
maintenance logbook. The FAA has amended paragraph (h) of this AD to
specify the two locations where the date of manufacture can be found.

Conclusion

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 reviewed the relevant data, considered the
comment received, and determined that air safety requires adopting this
AD as proposed. Accordingly, the FAA is issuing this AD to address the
unsafe condition on this product. Except for minor editorial changes,
and any other changes described previously, this AD is adopted as
proposed in the NPRM. None of the changes will increase the economic
burden on any operator.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Liebherr Service Bulletin CFD-F1958-26-01, dated
May 6, 2022, which specifies part numbers for affected sensing
elements.
The FAA reviewed Bombardier Service Bulletin 700-36-7503, dated
December 23, 2022, which specifies procedures for testing each leak
detection loop (LDL) sensing element installed on the airplane, marking
each serviceable sensing element with a witness mark, and replacing
each nonserviceable part with a serviceable part.
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.

Costs of Compliance

The FAA estimates that this AD affects 19 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:

Estimated Costs for Required Actions

The FAA has received no definitive data on which to base the cost
estimates for the on-condition actions specified in this AD. The FAA
estimates it takes up to 1.5 hours to replace a sensing element.

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.

Regulatory Findings

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,
(2) Will not affect intrastate aviation in Alaska, and
(3) Will 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 Amendment

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 adding the following new airworthiness
directive: