
[Federal Register Volume 79, Number 190 (Wednesday, October 1, 2014)]
[Proposed Rules]
[Pages 59157-59160]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[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: 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: 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 514-855-5000; fax 514-855-7401; email 
thd.crj@aero.bombardier.com; 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 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-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 800-647-5527) 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: 516-228-7329; fax: 516-794-5531; email: 
aziz.ahmed@faa.gov.

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://

[[Page 59158]]

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

[[Page 59159]]

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 516-794-5531. 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,

[[Page 59160]]

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 514-855-5000; fax 514-855-
7401; email thd.crj@aero.bombardier.com; 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 425-227-1221.

    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


