DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-2145; Project Identifier MCAI-2023-00358-T;
Amendment 39-22660; AD 2024-01-09]
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 all
Bombardier, Inc., Model BD-100-1A10 airplanes. This AD was prompted by
a report of a steering control unit (SCU) filter plate connector that
does not meet the certification requirements for exposure of electronic
components to high intensity radiated field environments, which could
result in malfunction of the nose wheel steering (NWS) system. This AD
requires determining if the SCU is an affected SCU, replacing all
affected SCUs, and rigging and testing the NWS control. This AD also
prohibits installing an affected SCU on any airplane. The FAA is
issuing this AD to address the unsafe condition on these products.

DATES: This AD is effective March 21, 2024.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of March 21,
2024.

ADDRESSES:
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2023-2145; 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 service information identified in this final rule,
contact Bombardier Business Aircraft Customer Response Center, 400
C[ocirc]te-Vertu Road West, Dorval, Qu[eacute]bec H4S 1Y9, Canada;
telephone 514-855-2999; email ac.yul@aero.bombardier.com; website
bombardier.com.
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. It is also available at
regulations.gov under Docket No. FAA-2023-2145.

FOR FURTHER INFORMATION CONTACT: William Reisenauer, Aviation Safety
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
telephone 516-228-7301; 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 all Bombardier, Inc.,
Model BD-100-1A10 airplanes. The NPRM published in the Federal Register
on November 13, 2023 (88 FR 77538). The NPRM was prompted by AD CF-
2023-13, dated February 24, 2023, issued by Transport Canada, which is
the aviation authority for Canada (referred to after this as the MCAI).
The MCAI states that the manufacturer of SCU part number (P/N) 46000-01
introduced a new filter plate connector that does not meet the
certification requirements related to the susceptibility of electronic
components to high intensity radiated field. According to the MCAI,
this non-compliant filter plate connector, if not replaced, could
result in a malfunction of the NWS system and cause un-commanded
steering or lateral excursion from the runway.
In the NPRM, the FAA proposed to require determining if the SCU is
an affected SCU, replacing all affected SCUs, and rigging and testing
the NWS control. In the NPRM, the FAA also proposed to prohibit
installing an affected SCU on any airplane. 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-2023-2145.

Discussion of Final Airworthiness Directive

Comments

The FAA received no comments on the NPRM or on the determination of
the cost to the public.

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 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, 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 Bombardier Service Bulletin 100-32-34, dated
October 18, 2021, and Bombardier Service Bulletin 350-32-010, dated
October 18, 2021. This service information specifies procedures for
determining the serial number of SCU P/N 46000-01, replacing any
affected SCU, and rigging and testing the NWS control. These documents
are distinct since they apply to different airplane serial numbers.
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 725 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:

Estimated Costs for Required Actions

The FAA has included all known costs in its cost estimate.
According to the manufacturer, however, some 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: