DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0876; Product Identifier 2019-NM-070-AD]
RIN 2120-AA64

Airworthiness Directives; Bombardier, Inc., Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for certain Bombardier, Inc., Model BD-700-1A10 and BD-700-1A11
airplanes. This proposed AD was prompted by a report that cracking was
discovered in a channel within a structural support member for the
rudder quadrant, rudder feel unit assembly, and environmental control
system due to fatigue. This proposed AD would require repetitive
inspections of the rudder quadrant box assembly for any cracking, and
modification of the rudder quadrant box assembly. The FAA is proposing
this AD to address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by January 30,
2020.

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 https://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 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, 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 https://www.regulations.
gov by searching for and locating Docket No. FAA-2019-0876;
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 NPRM, the regulatory evaluation, any comments received, and other
information. The street address for Docket Operations is listed above.
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Andrea Jimenez, Aerospace Engineer,
Airframe and Mechanical Systems Section, FAA, New York ACO Branch, 1600
Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7330;
fax 516-794-5531; email 9-avs-nyaco-cos@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

The FAA invites 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-2019-0876;
Product Identifier 2019-NM-070-AD" at the beginning of your comments.
The FAA specifically invites comments on the overall regulatory,
economic, environmental, and energy aspects of this NPRM. The FAA will
consider all comments received by the closing date and may amend this
NPRM because of those comments.

The FAA will post all comments received, without change, to https://www.
regulations.gov, including any personal information you provide.
The FAA will also post a report summarizing each substantive verbal
contact received about this NPRM.

Discussion

Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued Canadian Airworthiness Directive CF-
2019-11, dated March 22, 2019 (referred to after this as the Mandatory
Continuing Airworthiness Information, or "the MCAI"), to correct an
unsafe condition for certain Bombardier, Inc., Model BD-700-1A10 and
BD-700-1A11 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-2019-0876.

This proposed AD was prompted by a report that cracking was
discovered in a channel within a structural support member for the
rudder quadrant, rudder feel unit assembly, and environmental control
system due to fatigue. The FAA is proposing this AD to address cracking
in the rudder quadrant support structure, which can lead to progressive
deterioration in the performance of the systems it supports, and could
eventually lead to uncommanded rudder movement and bleed air leakage.
See the MCAI for additional background information.

Related Service Information Under 1 CFR Part 51

Bombardier has issued the following service information.

Bombardier Service Bulletin 700-53-054, dated October 1,
2018.

Bombardier Service Bulletin 700-53-5013, dated October 1,
2018.

Bombardier Service Bulletin 700-53-6012, dated October 1,
2018.

Bombardier Service Bulletin 700-1A11-53-029, dated October
1, 2018.

This service information describes procedures for repetitive
detailed visual inspections of the rudder quadrant box assembly for any
cracking. These documents are distinct since they apply to different
airplane models.

Bombardier also issued the following service information:

Bombardier Service Bulletin 700-53-052, dated October 1,
2018.

Bombardier Service Bulletin 700-53-6010, dated October 1,
2018.

Bombardier Service Bulletin 700-1A11-53-027, dated October
1, 2018.

Bombardier Service Bulletin 700-53-5011, dated October 1,
2018.

This service information describes procedures for modification of
the rudder quadrant box assembly. The modification includes surface and
bolt-hole eddy current inspections for cracking of the left-hand (LH)
channel; a detailed visual inspection for cracking of the forward and
aft half ribs and bottom and top skins; replacement of the rudder
quadrant box half ribs, air systems support fitting, and LH channel;
and installation of new rudder quadrant box back-up fittings. These
documents are distinct since they apply to different airplane models.

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

This product has been approved by the aviation authority of another
country, and is approved for operation in the United States. Pursuant
to a bilateral agreement with the State of Design Authority, the FAA
has been notified of the unsafe condition described in the MCAI and
service information referenced above. The FAA is proposing this AD
because the agency evaluated all the relevant information and
determined the unsafe condition described previously is likely to exist
or develop on other products of the same type design.

Proposed Requirements of This NPRM

This proposed AD would require accomplishing the actions specified
in the service information described previously, except as discussed
under "Differences Between this Proposed AD and the MCAI or Service
Information."

Differences Between This Proposed AD and the MCAI or Service
Information

Canadian Airworthiness Directive CF-2019-11, dated March 22, 2019,
states that if any cracking is found during the repetitive detailed
visual inspections of the rudder quadrant box assembly, the repair can
be done within 100 flight cycles after the inspection. However, this AD
requires that, for the LH channel, if the length of the crack exceeds
the upper limit, the repair must be done before further flight. In
addition, if the length of the crack for the LH channel is within the
upper limit, the repair must be done within 50 flight cycles. These
differences have been coordinated with TCCA.

Costs of Compliance

The FAA estimates that this proposed AD affects 123 airplanes of
U.S. registry. The FAA estimates the following costs to comply with
this proposed 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 Action

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.

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 and associated appliances to the
Director of the System Oversight Division.

Regulatory Findings

The FAA has 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. 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.

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):