DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0553; Product Identifier 2017-NM-138-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 an airworthiness directive (AD) for
certain Bombardier, Inc., Model DHC-8-102, -103, and -106 airplanes,
Model DHC-8-200 series airplanes, and Model DHC-8-300 series airplanes.
This proposed AD was prompted by reports of arcing and smoke emanating
from the windshield, caused by loose or damaged windshield heater
terminal lugs. This proposed AD would require revising the maintenance
or inspection program to incorporate maintenance review board (MRB)
tasks for general visual inspections of the windshield moisture seal.
This proposed AD would also require re-torqueing the windshield heater
terminal lugs, applying a coating to the windshield heater screw heads,
doing a chemical cleaning of the wiring and components, doing a visual
inspection of the wiring and components, doing an operational test of
the pilot's and co-pilot's windshield heating system, and repair if
necessary.

We are proposing this AD to address the unsafe condition on these
products.

DATES: We must receive comments on this proposed AD by August 20, 2018.

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., Q-Series Technical Help Desk, 123 Garratt Boulevard,
Toronto, Ontario M3K 1Y5, Canada; telephone 416-375-4000; fax 416-375-
4539; email thd.qseries@aero.bombardier.com; internet http://www.bombardier.com. You
may view this 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.

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-2018-
0553; 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 proposal. Send your comments to an address listed
under the ADDRESSES section. Include "Docket No. FAA-2018-0553;
Product Identifier 2017-NM-138-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-2017-25, dated July 31,
2017 (referred to after this as the Mandatory Continuing Airworthiness
Information, or "the MCAI"), to correct an unsafe condition for
certain Bombardier, Inc., Model DHC-8-102, -103, and -106 airplanes,
Model DHC-8-200 series airplanes, and Model DHC-8-300 series airplanes.
The MCAI states:

There have been several reports of arcing and smoke emanating
from the windshields. Investigation of these incidents revealed that
de-icing fluid and water could enter between the windshields and
side window posts, leading to possible damage of the windshield
heater terminal lugs creating arcing and smoke. In addition,
investigation also revealed that the windshield heater terminal lugs
tend to loosen over time. Loose terminal lugs could also have a
similar effect of arcing and smoke. Both events could lead to
burning of the lugs and, due to the excessive heat, cracking of the
windshields. If not corrected, these conditions could cause a loss
of cabin pressure resulting in an emergency descent.

Required actions include revising the maintenance or inspection
program, as applicable, to incorporate MRB tasks for general visual
inspections of the windshield moisture seal (for signs of cracking,
erosion, wear, or other damage), re-torqueing the windshield heater
terminal lugs, applying sealant to the windshield heater screw heads,
doing a chemical cleaning of the wiring and components, doing a general
visual inspection of the wiring and components for signs of cracking,
erosion, wear, or other damage, doing an operational test of the
pilot's and co-pilot's windshield heating system, and repair if necessary.

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-2018-0553.

Related Service Information Under 1 CFR Part 51

Bombardier has issued Service Bulletin 8-30-41, Revision A, dated
March 24, 2017. This service information describes procedures for re-
torqueing the windshield heater terminal lugs and applying Humisel
coating to the screw heads of the windshield heater, doing a chemical
cleaning and general visual inspection of the wiring and components,
and doing an operational test of the windshield heating system.

Bombardier has also issued the following service information, which
describes airworthiness limitation tasks for a general visual
inspection of the windshield moisture seal. These documents are
distinct since they apply to different airplane models.

de Havilland Dash 8 Series 100 Maintenance Task Card, Task
Number 5610/01, "General Visual Inspection of the Windshield Moisture
Seal," dated August 5, 2017.

de Havilland Dash 8 Series 200 Maintenance Task Card, Task
Number 5610/01, "General Visual Inspection of the Windshield Moisture
Seal," dated August 5, 2017.

de Havilland Dash 8 Series 300 Maintenance Task Card, Task
Number 5610/01, "General Visual Inspection of the Windshield Moisture
Seal," dated March 15, 2017.

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 the same
type design.

Differences Between This Proposed AD and the MCAI or Service
Information

The MCAI calls for revising the maintenance or inspection program,
as applicable, by incorporating certain temporary revisions (TRs) into
the Program Support Manual (PSM). This proposed AD instead calls for
incorporating certain task cards into the
PSM. We have determined that these task cards address the unsafe
condition in the same manner that the TRs would.

Costs of Compliance

We estimate that this proposed AD affects 63 airplanes of U.S. registry.

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

Estimated Costs for Required Actions

We have also determined that revising the maintenance or inspection
program takes an average of 90 work-hours per operator, although we
recognize that this number may vary from operator to operator. In the
past, we have estimated that this action takes 1 work-hour per
airplane. Since operators incorporate maintenance or inspection program
changes for their affected fleet(s), we have determined that a per-
operator estimate is more accurate than a per-airplane estimate.
Therefore, we estimate the total cost per operator to be $7,650 (90
work-hours x $85 per work-hour).

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