[Federal Register Volume 79, Number 190 (Wednesday, October 1, 2014)]
[Proposed Rules]
[Pages 59157-59160]
[FR Doc No: 2014-23376]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2014-0653; Directorate Identifier 2014-NM-057-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-600-2B19 (Regional Jet Series 100 &
440) airplanes. This proposed AD was prompted by reports of cracking on
the skin panels and skin splice joints and angles at certain stringers
at various locations between certain fuselage stations. This proposed
AD would require revising the maintenance or inspection program, as
applicable, to incorporate new or revised maintenance requirements and
airworthiness limitations, and incorporating structural repairs and
modifications to preclude widespread fatigue damage (WFD). We are
proposing this AD to detect and correct WFD, which could adversely
affect the structural integrity of the airplane.

DATES: We must receive comments on this proposed AD by November 17,
2014.

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:<PHONE_NUMBER>.
     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: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m., Monday
through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact
Bombardier, Inc., 400 C[ocirc]te-Vertu Road West, Dorval, Qu[eacute]bec
H4S 1Y9, Canada; telephone<PHONE_NUMBER>; fax<PHONE_NUMBER>; email
<EMAIL_ADDRESS>Internet http://www.bombardier.com. You
may view this referenced service information at the FAA, Transport
Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For information
on the availability of this material at the FAA, call<PHONE_NUMBER>.

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-2014-
0653; 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 proposed AD, the regulatory evaluation, any comments
received, and other information. The street address for the Docket
Operations office (telephone<PHONE_NUMBER>) is in the ADDRESSES section.
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Aziz Ahmed, Aerospace Engineer,
Airframe and Mechanical Systems Branch, ANE-171, FAA, New York Aircraft
Certification Office (ACO), 1600 Stewart Avenue, Suite 410, Westbury,
NY 11590; telephone:<PHONE_NUMBER>; fax:<PHONE_NUMBER>; email:
<EMAIL_ADDRESS>
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-2014-0653;
Directorate Identifier 2014-NM-057-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of this proposed AD. We
will consider all comments received by the closing date and may amend
this proposed AD 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 proposed AD.

Discussion

    Structural fatigue damage is progressive. It begins as minute
cracks, and those cracks grow under the action of repeated stresses.
This can happen because of normal operational conditions and design
attributes, or because of isolated situations or incidents such as
material defects, poor fabrication quality, or corrosion pits, dings,
or scratches. Fatigue damage can occur locally, in small areas or
structural design details, or globally. Global fatigue damage is
general degradation of large areas of structure with similar structural
details and stress levels. Multiple-site damage is global damage that
occurs in a large structural element such as a single rivet line of a
lap splice joining two large skin panels. Global damage can also occur
in multiple elements such as adjacent frames or stringers. Multiple-
site-damage and multiple-element-damage cracks are typically too small
initially to be reliably detected with normal inspection methods.
Without intervention, these cracks will grow, and eventually compromise
the structural integrity of the airplane, in a condition known as
widespread fatigue damage (WFD). As an airplane ages, WFD will likely
occur, and will certainly occur if the airplane is operated long enough
without any intervention.
    The FAA's WFD final rule (75 FR 69746, November 15, 2010) became
effective on January 14, 2011. The WFD rule requires certain actions to
prevent structural failure due to WFD throughout the operational life
of certain existing transport category airplanes and all of these
airplanes that will be certificated in the future. For existing and
future airplanes subject to the WFD rule, the rule requires that DAHs
establish a limit of validity (LOV) of the engineering data that
support the structural maintenance program. Operators affected by the
WFD rule may not fly an airplane beyond its LOV, unless an extended LOV
is approved.
    The WFD rule (75 FR 69746, November 15, 2010) does not require
identifying and developing maintenance actions if the DAHs can show
that such actions are not necessary to prevent WFD before the airplane
reaches the LOV. Many LOVs, however, do depend on accomplishment of
future maintenance actions. As stated in the WFD rule, any maintenance
actions necessary to reach the LOV will be mandated by airworthiness
directives through separate rulemaking actions.
    In the context of WFD, this action is necessary to enable DAHs to
propose LOVs that allow operators the longest operational lives for
their airplanes, and still ensure that WFD will not occur. This
approach allows for an implementation strategy that provides
flexibility to DAHs in determining the timing of service information
development (with FAA approval), while providing operators with
certainty regarding the LOV applicable to their airplanes.
    Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued Canadian Airworthiness Directive CF-
2014-07, dated January 31, 2014 (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. The MCAI states:

    Complete aeroplane fatigue testing on a CL-600-2B19 aeroplane by
the aeroplane manufacturer revealed the onset of simultaneous
cracking on the skin panels and skin splice joints and angles at
stringers number 6 and 20 at various locations between fuselage
stations (FS) 409.00 to FS 589.00.
    Cracks at multiple locations may reduce the residual strength of
the joint below the required levels if the cracks are not detectable
under the existing maintenance program established at the time of
certification. This multiple site damage (MSD) behavior, if not
corrected, could lead to widespread fatigue damage (WFD) and
adversely affect the structural integrity of the aeroplane and/or
could result in rapid decompression of the aeroplane.
    A Temporary Revision (TR) has been made to the Maintenance
Requirements Manual (MRM) to revise existing Airworthiness
Limitations (AWL) tasks and introduce new inspection tasks for the
detection of MSD. The aeroplane manufacturer is also developing a
structural modification to preclude WFD from occurring in the fleet
at these locations.
    This [Canadian] AD mandates the incorporation of the new and
revised AWL tasks [into the maintenance program], and a structural
modification to preclude WFD.

    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-2014-
0653.

Relevant Service Information

    Bombardier has issued the following AWL tasks to Part 2
Airworthiness Requirements, Revision 9, dated June 10, 2013, of
Appendix B, Airworthiness Limitations, of Bombardier CL-600-2B19,
Maintenance Requirements Manual, CSP A-053:
     AWL Task 53-41-109, ``Longitudinal Str. 6 splice at STR 6
and 20'';
     AWL Task 53-41-110, ``Longitudinal Str. 6 splice butt
strap at Str. 6, FS409.0 to FS617.0'';
     AWL Task 53-41-204, ``Frame splice angles at STR 6 and
20''; and
     AWL Task 53-41-205, ``Longitudinal skin splice at STR 6
and 20''.
    The actions described in this service information are intended to
correct the unsafe condition identified in the MCAI.

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.
    This proposed AD would require revisions to certain operator
maintenance documents to include new actions (e.g., inspections).
Compliance with these actions is required by 14 CFR 91.403(c). For
airplanes that have been previously modified, altered, or repaired in
the areas addressed by this proposed AD, the operator may not be able
to accomplish the actions described in the revisions. In this
situation, to comply with 14 CFR 91.403(c), the operator must request
approval for an alternative method of compliance according to paragraph
(j) of this proposed AD. The request should include a description of
changes to the required actions that will ensure the continued damage
tolerance of the affected structure.

Differences Between This Proposed AD and the MCAI or Service
Information

    The TCCA AD specifies that, if there are findings from the
airworthiness limitations section (ALS) inspection tasks, then
corrective action must be accomplished in accordance with Bombardier.
But this proposed AD does not include that requirement because
operators of U.S.-registered airplanes are required by general
airworthiness and operational regulations to use FAA-acceptable methods
when performing maintenance. We consider those methods to be adequate
to address any

corrective action necessitated by the findings of ALS inspections
required by this proposed AD.

Costs of Compliance

    We estimate that This proposed AD affects 526 airplanes of U.S.
registry.
    We also estimate that it would take about 1 work-hour per product
to comply with the basic requirements of this proposed AD. We have
received no definitive data that would enable us to provide cost
estimates for the repairs and modifications specified in this proposed
AD. The average labor rate is $85 per work-hour. Based on these
figures, we estimate the cost of this proposed AD on U.S. operators to
be $44,710, or $85 per product.

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.

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

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness
directive (AD):

Bombardier, Inc.: Docket No. FAA-2014-0653; Directorate Identifier
2014-NM-057-AD.

(a) Comments Due Date

    We must receive comments by November 17, 2014.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Bombardier, Inc. Model CL-600-2B19 (Regional
Jet Series 100 & 440) airplanes, certificated in any category,
serial numbers 7003 and subsequent.

(d) Subject

    Air Transport Association (ATA) of America Code 05, Periodic
Inspections.

(e) Reason

    This AD was prompted by reports of cracking on the skin panels
and skin splice joints and angles at certain stringers at various
locations between certain fuselage stations. We are issuing this AD
to detect and correct widespread fatigue damage, which could
adversely affect the structural integrity of the airplane.

(f) Compliance

    Comply with this AD within the compliance times specified,
unless already done.

(g) Revision of Maintenance or Inspection Program

    Within 60 days after the effective date of this AD: Revise the
maintenance or inspection program, as applicable, by incorporating
the airworthiness limitations (AWL) tasks specified in paragraphs
(g)(1) through (g)(4) of this AD, of Part 2 Airworthiness
Requirements, Revision 9, dated June 10, 2013, of Appendix B,
Airworthiness Limitations, of Bombardier CL-600-2B19, Maintenance
Requirements Manual, CSP A-053. The initial compliance times for the
tasks start from the applicable threshold times specified in Part 2
Airworthiness Requirements, Revision 9, dated June 10, 2013, of
Appendix B, Airworthiness Limitations, of Bombardier CL-600-2B19,
Maintenance Requirements Manual, CSP A-053; except that, for
airplanes that have accumulated more than 38,000 total flight cycles
as of the effective date of this AD, the initial compliance time for
the AWL tasks is before the accumulation of 2,000 flight cycles
after the effective date of this AD.
    (1) AWL Task 53-41-109, ``Longitudinal Str. 6 splice at STR 6
and 20.''
    (2) AWL Task 53-41-110, ``Longitudinal Str. 6 splice butt strap
at Str. 6, FS409.0 to FS617.0.''
    (3) AWL Task 53-41-204, ``Frame splice angles at STR 6 and 20.''
    (4) AWL Task 53-41-205, ``Longitudinal skin splice at STR 6 and
20.''

(h) No Alternative Actions or Intervals

    After the maintenance or inspection program has been revised as
required by paragraph (g) of this AD, no alternative actions (e.g.,
inspections) or intervals may be used unless the actions or
intervals are approved as an alternative method of compliance (AMOC)
in accordance with the procedures specified in paragraph (j)(1) of
this AD.

(i) Repairs and Modifications

    Before the accumulation of 60,000 total flight cycles: Install
repairs and modifications to preclude widespread fatigue damage at
locations specified in paragraphs (g)(1) through (g)(4) of this AD,
using a method approved by the Manager, New York ACO, ANE-170, FAA;
or Transport Canada Civil Aviation (TCCA); or Bombardier, Inc.'s
TCCA Design Approval Organization (DAO).

(j) Other FAA AD Provisions

    The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, New
York ACO, ANE-170, FAA, has the authority to approve AMOCs for this
AD, if requested using the procedures found in 14 CFR 39.19. In
accordance with 14 CFR 39.19, send your request to your principal
inspector or local Flight Standards District Office, as appropriate.
If sending information directly to the ACO, send it to ATTN: Program
Manager, Continuing Operational Safety, FAA, New York ACO, 1600
Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-
7300; fax<PHONE_NUMBER>. Before using any approved AMOC, notify your
appropriate principal inspector, or lacking a principal inspector,
the manager of the local flight standards district office/
certificate holding district office. The AMOC approval letter must
specifically reference this AD.
    (2) Contacting the Manufacturer: For any requirement in this AD
to obtain corrective actions from a manufacturer, the action must be
accomplished using a method approved by the Manager, New York ACO,
ANE-170, Engine and Propeller Directorate, FAA; or Transport Canada
Civil Aviation (TCCA); or Bombardier, Inc.'s TCCA Design Approval
Organization (DAO). If approved by the DAO,

the approval must include the DAO-authorized signature.

(k) Related Information

    (1) Refer to Mandatory Continuing Airworthiness Information
(MCAI) Canadian Airworthiness Directive CF-2014-07, dated January
31, 2014, for related information. This MCAI may be found in the AD
docket on the Internet at http://www.regulations.gov by searching
for and locating Docket No. FAA-2014-0653.
    (2) For service information identified in this AD, contact
Bombardier, Inc., 400 C[ocirc]te-Vertu Road West, Dorval,
Qu[eacute]bec H4S 1Y9, Canada; telephone<PHONE_NUMBER>; fax 514-855-
7401; email<EMAIL_ADDRESS>Internet http://www.bombardier.com. You may view this service information at the
FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton,
WA. For information on the availability of this material at the FAA,
call<PHONE_NUMBER>.

    Issued in Renton, Washington, on September 20, 2014.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2014-23376 Filed 9-30-14; 8:45 am]
BILLING CODE 4910-13-P