DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0526; Product Identifier 2019-NM-023-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: The FAA proposes to supersede Airworthiness Directive (AD) AD
2015-24-04, which applies to certain Bombardier, Inc., Model CL-600-
2B19 (Regional Jet Series 100 & 440) airplanes, Model CL-600-2C10
(Regional Jet Series 700, 701, & 702) airplanes, Model CL-600-2D15
(Regional Jet Series 705) airplanes, Model CL-600-2D24 (Regional Jet
Series 900) airplanes, and Model CL-600-2E25 (Regional Jet Series 1000)
airplanes. AD 2015-24-04 requires repetitive inspections of the cage
assembly for damaged or detached window louver panel assemblies (WLPAs)
and blowout panels (BOPs), and corrective actions if necessary. Since
AD 2015-24-04 was issued, the FAA has determined that new airworthiness
limitations, as well as additional actions, are necessary to address
the unsafe condition. This proposed AD would require one-time
inspections of the WLPAs and BOPs, corrective actions if necessary, and
a revision of the existing maintenance or inspection program, as
applicable, to incorporate new airworthiness limitations, which would
terminate the proposed inspection requirement. 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 November 4,
2019.

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
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.

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-2019-0526;
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: Darren Gassetto, Aerospace Engineer,
Mechanical Systems and Administrative Services Section, FAA, New York
ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
telephone 516-228-7323; 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-2019-0526; Product
Identifier 2019-NM-023-AD" at the beginning of your comments. The FAA
specifically invites comments on the overall regulatory, economic,
environmental, and energy aspects of this proposed AD. The FAA will
consider all comments received by the closing date and may amend this
proposed AD based on those comments.

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

Discussion

The FAA issued AD 2015-24-04, Amendment 39-18336 (80 FR 74673,
November 30, 2015) ("AD 2015-24-04"), for certain Bombardier, Inc.,
Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes, Model CL-
600-2C10 (Regional Jet Series 700, 701, & 702) airplanes, Model CL-600-
2D15 (Regional Jet Series 705) airplanes, Model CL-600-2D24 (Regional
Jet Series 900) airplanes, and Model CL-600-2E25 (Regional Jet Series
1000) airplanes. AD 2015-24-04 requires repetitive inspections of the
cage assembly, WLPAs, and BOPs, and corrective actions if necessary. AD
2015-24-04 resulted from reports of damaged decompression WLPAs, and
detached BOPs. The FAA issued AD 2015-24-04 to address damaged or
detached WLPAs and BOPs. A detached WLPA or BOP could delay smoke
detection in the cargo compartment in the event of a fire, and could
result in an uncontrolled fire in the cargo compartment.

Actions Since AD 2015-24-04 Was Issued

Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued Canadian AD CF-2015-28R2, dated
February 4, 2019 (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, Model CL-600-2C10 (Regional Jet Series
700, 701, & 702) airplanes, Model CL-600-2D15 (Regional Jet Series 705)
airplanes, Model CL-600-2D24 (Regional Jet Series 900) airplanes, and
Model CL-600-2E25 (Regional Jet Series 1000) airplanes. 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-2019-0526.

This proposed AD was prompted by reports of damaged decompression
window louver panel assemblies (WLPAs), and detached blowout panels
(BOPs). We are proposing this AD to address damaged or detached WLPAs
and BOPs, which could delay smoke detection in the cargo compartment in
the event of a fire and result in an uncontrolled fire in the cargo
compartment. See the MCAI for additional background information.

Explanation of Retained Requirements

This proposed AD supersedes AD 2015-24-04, and this proposed AD
retains all of the requirements of AD 2015-24-04. Those requirements
are restated with compliance time changes that are relieving and based
on the compliance times referenced in an earlier revision of the
Canadian AD (CF-2015-28R1) which, in turn, was revised by Canadian AD
CF-2015-28R2. For clarity and to avoid unnecessary differences between
this proposed AD and the MCAI, we have not separated the requirements
of this proposed AD into restated requirements and new requirements as
is our usual practice.

Related Service Information Under 1 CFR Part 51

Bombardier has issued the following service information:

Bombardier Service Bulletin 601R-25-201, Revision C, dated
May 11, 2017.

Bombardier Service Bulletin 670BA-25-100, Revision C,
dated May 11, 2017. This service information describes procedures for
repetitive detailed inspections for damage of the cage assembly, WLPAs,
and BOPs, and repair or replacement of damaged parts. These documents
are unique since they apply to different airplane models.

Bombardier has also issued the following service information:

Bombardier CRJ Series Regional Jet Maintenance
Requirements Manual (MRM), CSP A-053, Part 2, Appendix A, Certification
Maintenance Requirements (CMR), Task C26-25-115-01, as specified in CRJ
Series Regional Jet Temporary Revision (TR) 2A-69, dated August 30,
2018.

Bombardier CRJ Series Regional Jet MRM, CSP B-053, Part 1,
and Maintenance Review Board Report (MRBR) Task 255000-208, as
specified in TR MRB-0079, dated May 29, 2017.

This service information describes an airworthiness limitation task
for a detailed inspection of the aft cargo compartment WLPAs and BOPs.
These TRs are unique 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 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.

Costs of Compliance

The FAA estimates that this proposed AD affects 1,008 airplanes of
U.S. registry. The FAA estimates the following costs to comply with
this proposed AD:

Estimated Costs for Required Actions *

* Table does not include estimated costs for revising the maintenance or
inspection program.

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

The FAA has received no definitive data that would enable the
agency 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.

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 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 removing Airworthiness Directive (AD)
2015-24-04, Amendment 39-18336 (80 FR 74673, November 30, 2015), and
adding the following new AD: