DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-1246; Product Identifier 2017-NM-086-AD; Amendment
39-19297; AD 2018-11-09]
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) 2014-02-01,
which applied to certain Bombardier, Inc., Model CL-600-2C10 (Regional
Jet Series 700, 701, & 702), Model CL-600-2D15 (Regional Jet Series
705), and Model CL-600-2D24 (Regional Jet Series 900) airplanes. AD
2014-02-01 required repetitive inspections of the rudder travel limiter
(RTL) return springs and primary actuator, and corrective actions if
necessary; and replacement of certain RTL return springs. This AD
requires an inspection of the RTL return springs for signs of chafing;
an inspection of the casing of the primary actuator for signs of
chafing or missing paint; replacement of the RTL return springs; and an
inspection of the lugs of the RTL limiter arm assembly for cracks, and
modification or replacement, as applicable; and applicable corrective
actions. This AD also adds airplanes to the applicability. This AD was
prompted by reports that when installing the RTL return springs, the
RTL limiter arm assembly lug(s) can become deformed. We are issuing
this AD to address the unsafe condition on these products.

DATES: This AD is effective July 10, 2018.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of July 10,
2018.

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 Standards 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 http://www.regulations.gov by searching for and locating
Docket No. FAA-2017-1246.

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-2017-
1246; 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: Cesar Gomez, Aerospace Engineer,
Airframe and Mechanical Systems Section, FAA, New York ACO Branch, 1600
Stewart Avenue, Suite 410, Westbury, NY 11590; telephone: 516-228-7318;
fax: 516-794-5531.

SUPPLEMENTARY INFORMATION:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to supersede AD 2014-02-01, Amendment 39-17729 (79 FR 7382,
February 7, 2014) (``AD 2014-02-01''). AD 2014-02-01 applied to certain
Bombardier, Inc., Model CL-600-2C10 (Regional Jet Series 700, 701, &
702), Model CL-600-2D15 (Regional Jet Series 705), and Model CL-600-
2D24 (Regional Jet Series 900) airplanes. The NPRM published in the
Federal Register on January 16, 2018 (83 FR 2090). The NPRM was
prompted by reports that when installing RTL return spring part number
BA-670-93468-1, the RTL limiter arm assembly lug(s) can become deformed
when the RTL return spring attachment bolt is torqued; and the
determination that additional airplanes are affected by the unsafe
condition. The NPRM proposed to require an inspection of the RTL return
springs for signs of chafing; an inspection of the casing of the
primary actuator for signs of chafing or missing paint; replacement of
the RTL return springs; and an inspection of the lugs of the RTL
limiter arm assembly for cracks, and modification or replacement, as
applicable; and applicable corrective
actions. The NPRM also proposed to add airplanes to the applicability.
We are issuing this AD to prevent deformed RTL limiter arm assembly
lug(s), which can lead to failure of the RTL limiter arm assembly
lug(s). In combination with failure of the RTL, failure of the RTL
limiter arm assembly lug(s) could result in reduced controllability of
the airplane.
Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued Canadian AD CF-2017-19, dated June 6,
2017 (referred to after this as the Mandatory Continuing Airworthiness
Information, or ``the MCAI''), to correct an unsafe condition for
certain Bombardier, Inc., Model CL-600-2C10 (Regional Jet Series 700,
701, & 702), Model CL-600-2D15 (Regional Jet Series 705), and Model CL-
600-2D24 (Regional Jet Series 900) airplanes. The MCAI states:

Transport Canada AD CF-2010-18R1 [which corresponds to FAA AD
2014-02-01] mandated a repetitive inspection and introduced a new
rudder travel limiter (RTL) return spring, part number (P/N) BA670-
93468-1, to correct the potential dormant RTL spring failure. This
[Canadian] AD is issued to supersede the repetitive inspection and
the replacement of the RTL spring due to discoveries made after the
issuance of [Canadian] AD CF-2010-18R1.
When installing the RTL return spring P/N BA670-93468-1 as
mandated by [Canadian] AD CF-2010-18R1, it was found that it is
possible for the RTL limiter arm assembly lug to be deformed. The
lugs become bent when the RTL return spring attachment bolt is
torqued. This condition, if not corrected, can lead to failure of
the limiter arm assembly lug. In combination with failure of the
RTL, failure of the limiter arm assembly lug could affect the
controllability of the aeroplane.
This [Canadian] AD mandates the inspection for cracked RTL
limiter arm lugs and modification of the RTL limiter arm to prevent
the RTL limiter arm lugs from bending during RTL assembly.

Required actions include: A detailed visual inspection of the RTL
return springs for signs of chafing; a detailed visual inspection of
the casing of the primary actuator for signs of chafing or missing
paint; replacement of the RTL return springs; an eddy current
inspection of the lugs of the RTL limiter arm assembly for cracks, and
modification or replacement of the RTL limiter arm assembly, as
applicable; and applicable corrective actions. Corrective actions
include: replacement of the RTL return springs, repair of the primer
and topcoat of the primary actuator, and replacement of the primary
actuator. 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-2017-1246.

Comments

We gave the public the opportunity to participate in developing
this AD. We considered the comment received. The Air Line Pilots
Association, International supported the NPRM.

Conclusion

We reviewed the available data, including the comment received, 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

Bombardier has issued Bombardier Service Bulletin 670BA-27-070,
Revision B, dated March 31, 2017. This service information describes
procedures for an inspection of the RTL return springs for signs of
chafing; an inspection of the casing of the primary actuator for signs
of chafing or missing paint; replacement of the RTL return springs; and
an inspection of the lugs of the RTL limiter arm assembly for cracks,
and modification or replacement, as applicable; and applicable
corrective actions. 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 544 airplanes of U.S. registry. We
estimate the following costs to comply with this AD:

Estimated Costs for Required Actions

We have received no definitive data that would enable us to provide
cost estimates for the on-condition actions specified in this AD.

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.
This AD is issued in accordance with authority delegated by the
Executive Director, Aircraft Certification Service, as authorized by
FAA Order 8000.51C. In accordance with that order, issuance of ADs is
normally a function of the Compliance and Airworthiness Division, but
during this transition period, the Executive Director has delegated the
authority to issue ADs applicable to transport category airplanes to
the Director of the System Oversight Division.

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)
2014-02-01, Amendment 39-17729 (79 FR 7382, February 7, 2014) and
adding the following new AD: