DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-9190; Directorate Identifier 2016-NM-087-AD;
Amendment 39-18797; AD 2017-04-02]
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: We are superseding Airworthiness Directive (AD) 2014-23-06 for
certain Bombardier, Inc. Model CL-600-2B19 (Regional Jet Series 100 &
440) airplanes. AD 2014-23-06 required modifying the main landing gear
(MLG) by installing a new bracket on the left and right lower aft-wing
planks. This new AD requires modification of the MLG with an improved
design. This AD was prompted by a report indicating that inboard and
outboard hydraulic lines of the brakes were found connected to the
incorrect ports on the swivel assembly of the MLG. We are issuing this
AD to address the unsafe condition on these products.

DATES: This AD is effective March 28, 2017.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of March 28,
2017.

ADDRESSES: For service information identified in this final rule,
contact Bombardier, Inc., 400 Cote-Vertu Road West, Dorval,
Quebec H4S 1Y9, Canada; Widebody Customer Response Center North
America toll-free telephone 1-866-538-1247 or direct-dial telephone 1-
514-855-2999; fax 514-855-7401; email ac.yul@aero.bombardier.com;
Internet http://www.bombardier.com. You may view this referenced
service information at the FAA, Transport Airplane Directorate, 1601
Lind Avenue SW., Renton, WA. For information on the availability of
this material at the FAA, call 425-227-1221. It is also available on
the Internet at http://www.regulations.gov by searching for and
locating Docket No. FAA-2016-9190.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov
by searching for and locating Docket No. FAA-2016-
9190; or in person at the Docket Management Facility between 9 a.m. and
5 p.m., Monday through Friday, except Federal holidays. The AD docket
contains this AD, the regulatory evaluation, any comments received, and
other information. The address for the Docket Office (telephone 800-
647-5527) is Docket Management Facility, 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: Fabio Buttitta, Aerospace Engineer,
Airframe and Mechanical Systems Branch, ANE-171, FAA, New York Aircraft
Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, NY
11590; telephone 516-228-7303; fax 516-794-5531.

SUPPLEMENTARY INFORMATION:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to supersede AD 2014-23-06, Amendment 39-18022 (79 FR 69037,
November 20, 2014) (``AD 2014-23-06''). AD 2014-23-06 applied to
certain Bombardier, Inc. Model CL-600-2B19 (Regional Jet Series 100 &
440) airplanes. The NPRM published in the Federal Register on October
24, 2016 (81 FR 73042). The NPRM was prompted by a report indicating
that inboard and outboard hydraulic lines of the brakes were found
connected to the incorrect ports on the swivel assembly of the MLG. The
NPRM proposed to require modification of the MLG with an improved
design. We are issuing this AD to prevent incorrect installation of the
brake hydraulic lines, which could cause the brakes and the anti-skid
system to operate incorrectly, and result in catastrophic failure of
the airplane during a high-speed rejected takeoff.
Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued Canadian Airworthiness Directive CF-
2014-10R1, dated May 4, 2016 (referred to after this as the Mandatory
Continuing Airworthiness Information, or ``the MCAI''), to correct an
unsafe condition for certain Bombardier, Inc. Model CL-600-2B19
(Regional Jet Series 100 & 440) airplanes. The MCAI states:

Cases of inboard and outboard hydraulic brake lines connected to
the incorrect port of the swivel assembly on the main landing gear
were found in service. Cross-connected brake hydraulic lines can
cause the brakes and/or the anti-skid system to operate incorrectly.
During a high speed rejected take-off, inability for the brakes to
operate correctly could be catastrophic. The original issue of this
[Canadian] AD mandated the modification to prevent inadvertent
cross-connection of the inboard and outboard hydraulic brake lines.
Following the initial release of this [Canadian] AD, operators
reported that the modifications required by Bombardier Service
Bulletin (SB) 601R-32-110 Rev. NC., dated 19 December 2013, still
have a potential for incorrect connection. Subsequently, the SB has
been revised to introduce a modified design and this [Canadian] AD
revision is issued to mandate the incorporation of the modified
design.

You may examine the MCAI in the AD docket on the Internet at http://
www.regulations.gov by searching for and locating Docket No. FAA-2016-
9190.

Comments

We gave the public the opportunity to participate in developing
this AD. We received no comments on the NPRM or on the determination of
the cost to the public.

Conclusion

We reviewed the available data and determined that air safety and
the public interest require adopting this AD as proposed except for
minor editorial changes. We have determined that these minor changes:
Are consistent with the intent that was proposed in the
NPRM for correcting 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

We reviewed Bombardier Service Bulletin 601R-32-110, Revision C,
dated May 4, 2016. The service information describes procedures for
modifying the MLG by installing a block on the left and right lower
aft-wing planks. 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

We estimate that this AD affects 526 airplanes of U.S. registry.
We also estimate that it will take about 9 work-hours per product
to comply with the basic requirements of this AD. The average labor
rate is $85 per work-hour. Required parts will cost about $190 per
product. Based on these figures, we estimate the cost of this AD on
U.S. operators to be $502,330, or $955 per product.

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.
We are 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

We determined that 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. Is not a ``significant rule'' under the DOT Regulatory Policies
and Procedures (44 FR 11034, February 26, 1979);
3. Will not affect intrastate aviation in Alaska; and
4. 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 removing Airworthiness Directive (AD)
2014-23-06, Amendment 39-18022 (79 FR 69037, November 20, 2014), and
adding the following new AD: