DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0030; Project Identifier MCAI-2020-01395-T;
Amendment 39-21555; AD 2021-10-22]
RIN 2120-AA64

Airworthiness Directives; Bombardier, Inc., Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Bombardier, Inc., Model BD-700-1A10 airplanes. This AD was
prompted by a report indicating that during installation, a fuel pipe
bracket assembly on the intermediate rib in the center fuel tank was
mislocated, resulting in an offset between the fitting assembly and the
refuel/defuel tube assembly. This AD requires modification of the fuel
pipe bracket assembly, including all related investigative actions and
corrective actions, if necessary; and performing an operational test of
the refuel and defuel system. The FAA is issuing this AD to address the
unsafe condition on these products.

DATES: This AD is effective July 6, 2021.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of July 6,
2021.

ADDRESSES: For service information identified in this final rule,
contact Bombardier, Inc., 400 Cote-Vertu Road West, Dorval,
Quebec H4S 1Y9, Canada; telephone 514-855-5000; fax 514-855-
7401; email thd.crj@aero.bombardier.com; internet https://
www.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 on the
internet at https://www.regulations.gov by searching for and locating
Docket No. FAA-2021-0030.

Examining the AD Docket

You may examine the AD docket on the internet at https://www.regulations.
gov by searching for and locating Docket No. FAA-2021-
0030; 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, 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.

FOR FURTHER INFORMATION CONTACT: Siddeeq Bacchus, Aerospace Engineer,
Mechanical Systems and Administrative Services Section, FAA, New York
ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
telephone 516-228-7362; fax 516-794-5531; email 9-avs-nyaco-cos@faa.gov.

SUPPLEMENTARY INFORMATION:

Background

Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued TCCA AD CF-2020-37, dated October 9,
2020 (also referred to as the Mandatory Continuing Airworthiness
Information, or the MCAI), to correct an unsafe condition for certain
Bombardier, Inc., Model BD-700-1A10 airplanes. You may examine the MCAI
in the AD docket on the internet at https://www.regulations.gov by
searching for and locating Docket No. FAA-2021-0030.
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-700-1A10 airplanes. The NPRM published in the Federal
Register on February 24, 2021 (86 FR 11191). The NPRM was prompted by a
report indicating that during installation, a fuel pipe bracket
assembly on the intermediate rib in the center fuel tank was
mislocated, resulting in an offset between the fitting assembly and the
refuel/defuel tube assembly. The NPRM proposed to require modification
of the fuel pipe bracket assembly, including all related investigative
actions and corrective actions, if necessary; and performing an
operational test of the refuel and defuel system. The FAA is issuing
this AD to address the offset, which could cause a preload on the fuel
pipes and reduce their ability to absorb shock or vibration-induced
loads, making the tube and clamp more prone to stress corrosion
cracking. This could lead to failure of the coupling and the bracket
and p-clamp assembly, resulting in fuel leakage and loss of electrical
bonding between fuel pipes, and lightning-induced sparking that could
induce fuel ignition. See the MCAI for additional background
information.

Comments

The FAA gave the public the opportunity to participate in
developing this final rule. The FAA received no comments on the NPRM or
on the determination of the cost to the public.

Conclusion

The FAA reviewed the relevant data and determined that air safety
and the public interest require adopting this final rule as proposed,
except for minor editorial changes. The FAA has determined that these
minor changes:
Are consistent with the intent that was proposed in the
NPRM for addressing the unsafe condition; and
Do not add any additional burden upon the public than was
already proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

Bombardier has issued Service Bulletin 700-28-6006, dated June 1,
2020. This service information describes procedures for a modification
of the fuel pipe bracket assembly, including investigative actions (a
detailed visual inspection of the fuel pipe assembly for any damaged
paint, permanent deformation, corrosion, cracking, gouges, dents, or
deep scratches); installation of certain new parts; replacement of the
fuel pipe and fuel pipe bracket assembly, if necessary; and an
operational test of the refuel and defuel system. 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 51 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:

Estimated Costs for Required Actions

The FAA estimates the following costs to do any necessary on-
condition action 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 this on-condition action:

Estimated Costs of On-Condition Actions

According to the manufacturer, some or all of the costs of this AD
may be covered under warranty, thereby reducing the cost impact on
affected operators. The FAA does not control warranty coverage for
affected operators. As a result, the FAA has included all known costs
in the cost estimate.

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.

Adoption of 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: