DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-0810; Product Identifier 2017-NM-045-AD]
RIN 2120-AA64

Airworthiness Directives; Bombardier, Inc., Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for
certain Bombardier, Inc., Model CL-600-2C10 (Regional Jet Series 700,
701, & 702), Model CL-600-2D15 (Regional Jet Series 705), Model CL-600-
2D24 (Regional Jet Series 900), and Model CL-600-2E25 (Regional Jet
Series 1000) airplanes. This proposed AD was prompted by a report of a
smoke-in-cabin event due to a non-sustaining electrical fire. This
proposed AD would require installation of protective sleeves on the
bonding jumper wires of affected galleys and lavatories. We are
proposing this AD to address the unsafe condition on these products.

DATES: We must receive comments on this proposed AD by October 30, 2017.

ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, by any of the following methods:

Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the
instructions for submitting comments.

Fax: 202-493-2251.

Mail: U.S. Department of Transportation, Docket Operations, M-30, West
Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE.,
Washington, DC 20590.

Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.

For service information identified in this NPRM, contact Bombardier, Inc.,
400 Cote Vertu Road West, Dorval, Quebec H4S1Y9, 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 service information at the FAA, Transport Standards Branch, 1601 Lind
Avenue SW., Renton, WA. For information on the availability of this
material at the FAA, call 425-227-1221.

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-2017-0810;
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 NPRM, the regulatory evaluation, any comments received,
and other information. The street address for the Docket Operations
office (telephone: 800-647-5527) is in the ADDRESSES section. Comments
will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Assata Dessaline, Aerospace Engineer,
Avionics and Administrative Services Section, FAA, New York ACO Branch,
1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone: 516-228-
7301; fax: 516-794-5531.

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments
about this proposed AD. Send your comments to an address listed under
the ADDRESSES section. Include "Docket No. FAA-2017-0810; Product Ident-
ifier 2017-NM-045-AD" at the beginning of your comments. We specifically
invite comments on the overall regulatory, economic, environmental, and
energy aspects of this NPRM. We will consider all comments received by
the closing date and may amend this NPRM based on those comments.

We will post all comments we receive, without change, to http://www.
regulations.gov, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact we
receive about this NPRM.

Discussion

Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued Canadian AD CF-2016-20R1, dated
February 3, 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),
Model CL-600-2D24 (Regional Jet Series 900), and Model CL-600-2E25
(Regional Jet Series 1000) airplanes. The MCAI states:

A CRJ900 aeroplane reported a smoke in cabin event due to a non-
sustaining electrical fire. The source of smoke was traced to a
burnt heated water supply line behind the #2 Galley. The surrounding
insulation was also found burnt.

The root cause of this electrical fire was an electrical short
between an un-insulated bonding jumper and a terminal block carrying
115 volts AC. The circuit resistance was high enough and the circuit
breakers that protect the wiring did not trip open.

Electrical short of a bonding jumper may result in in-flight
smoke or fire events as well as failure of avionics equipment due to
possible water spray or leakage from a damaged water supply line.
The likelihood of this happening is increased by the removal and
installation of the galley or lavatory during maintenance, allowing
the bonding jumper to become wedged under the terminal block.
* * * * *

Revision 1 of this [Canadian] AD is issued to mandate [the
installation of protective sleeves on the galley and lavatory
bonding jumper wires in accordance with] Bombardier Service Bulletin
(SB) 670BA-25-101 Revision B dated 12 January 2017. * * *

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-2017-0810.

Related Service Information Under 1 CFR Part 51

Bombardier, Inc., has issued Bombardier Service Bulletin 670BA-25-
101, Revision B, dated January 12, 2017. The service information
describes procedures for installation of protective sleeves on the
bonding jumper wires of affected galleys and lavatories. 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.

FAA's Determination and Requirements of This Proposed AD

This product has been approved by the aviation authority of another
country, and is approved for operation in the United States. Pursuant
to our bilateral agreement with the State of Design Authority, we have
been notified of the unsafe condition described in the MCAI and service
information referenced above. We are proposing this AD because we
evaluated all pertinent information and determined an unsafe condition
exists and is likely to exist or develop on other products of these
same type designs.

Costs of Compliance

We estimate that this proposed AD affects 544 airplanes of U.S.
registry.

We estimate the following costs to comply with this proposed AD:

Estimated Costs

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 proposed 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 proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD would 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 this proposed
regulation:

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.

The Proposed Amendment

Accordingly, under the authority delegated to me by the
Administrator, the FAA proposes to amend 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 (AD):