DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-0935; Project Identifier MCAI-2022-01311-T;
Amendment 39-22491; AD 2023-13-06]
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
an in-service event where the nose gear door amber caution message
displayed on the crew alerting system during the initial climb after
gear retraction. This AD requires revising the existing maintenance or
inspection program, as applicable, to incorporate new or more
restrictive airworthiness limitations. The FAA is issuing this AD to
address the unsafe condition on these products.

DATES: This AD is effective September 1, 2023.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of September 1,
2023.

ADDRESSES:
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2023-0935; 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
Cote-Vertu Road West, Dorval, Quebec 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-2023-0935.

FOR FURTHER INFORMATION CONTACT: Gabriel D. Kim, Aviation Safety
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
telephone 516-228-7343; 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 April 25, 2023 (88 FR 24924). The NPRM was prompted by AD CF-2022-
57, dated October 5, 2022, issued by Transport Canada, which is the
aviation authority for Canada (referred to after this as the MCAI). The
MCAI states an in-service event occurred where the nose gear door amber
caution message displayed on the crew alerting system during the
initial climb after gear retraction. After landing, an inspection found
that one of the nose landing gear (NLG) door hinge fitting assemblies
were broken. The absence of an inspection to detect cracks in the
fillet radii of the NLG door hinge fitting could result in door
misalignment with the airplane.
In the NPRM, the FAA proposed to require revising the existing
maintenance or inspection program, as applicable, to incorporate new or
more restrictive airworthiness limitations. The FAA is issuing this AD
to address cracked fillet radii of NLG door hinge fittings. The unsafe
condition, if not addressed, could result in a NLG door misalignment,
which could increase the drag and yawing movement during flight, could
cause jamming of the door affecting the ability to extend or retract
the NLG, or could potentially result in the NLG door detaching from the
airplane.
You may examine the MCAI in the AD docket at regulations.gov under
Docket No. FAA-2023-0935.

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 Challenger 300 BD-100 Time Limits/
Maintenance Checks Temporary Revision (TR) TR5-2-101, dated June 30,
2022; and (Bombardier) Challenger 350 BD-100 Time Limits/Maintenance
Checks Temporary Revision TR5-2-30, dated June 30, 2022. This service
information specifies new or more restrictive airworthiness limitations
for the NLG door hinge fittings fillet radii. These documents are
distinct because they apply to different airplane configurations.
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, would affect 716 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:
The FAA has determined that revising the maintenance or inspection
program takes an average of 90 work-hours per operator, although the
agency recognizes that this number may vary from operator to operator.
Since operators incorporate maintenance or inspection program changes
for their affected fleet(s), the FAA has determined that a per-operator
estimate is more accurate than a per-airplane
estimate. Therefore, the agency estimates the average total cost per
operator to be $7,650 (90 work-hours x $85 per work-hour).

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: