
[Federal Register: September 28, 2009 (Volume 74, Number 186)]
[Proposed Rules]               
[Page 49346-49349]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr28se09-17]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2009-0792; Directorate Identifier 2009-NM-057-AD]
RIN 2120-AA64

 
Airworthiness Directives; Bombardier Model CL-600-2C10 (Regional 
Jet Series 700, 701, & 702), Model CL-600-2D15 (Regional Jet Series 
705), and Model CL-600-2D24 (Regional Jet Series 900) 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 the 
products listed above. This proposed AD results from mandatory 
continuing airworthiness information (MCAI) originated by an aviation 
authority of another country to identify and correct an unsafe 
condition on an aviation product. The MCAI describes the unsafe 
condition as:

    Bombardier Aerospace has completed a system safety review of the 
CL-600-2C10/CL600-2D15/CL-600-2D24 aircraft fuel system against the 
new fuel tank safety standards, introduced in Chapter 525 of the 
Airworthiness Manual through Notice of Proposed Amendment (NPA) 
2002-043. The identified non-compliances were assessed using 
Transport Canada Policy Letter No. 525-001 to determine if mandatory 
corrective action was required.
    The assessment showed that certain hydraulic system failure 
scenarios could lead

[[Page 49347]]

to a rapid overheat in the hydraulic lines without giving flight 
crew sufficient time to react before the No. 1 and No. 2 hydraulic 
system tubing inside the fuel tank reaches the fuel auto ignition 
temperature. This could result in a fuel tank explosion.

* * * * *
The proposed AD would require actions that are intended to address the 
unsafe condition described in the MCAI.

DATES: We must receive comments on this proposed AD by November 12, 
2009.

ADDRESSES: You may send comments 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; e-mail 
thd.crj@aero.bombardier.com; Internet http://www.bombardier.com. You 
may review copies of the referenced service information at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington. For information on the availability of this material at the 
FAA, call 425-227-1221 or 425-227-1152.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Operations office 
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: Christopher Alfano, Aerospace 
Engineer, Airframe and Propulsion Branch, ANE-171, FAA, New York 
Aircraft Certification Office, 1600 Stewart Avenue, Suite 410, 
Westbury, New York 11590; telephone (516) 228-7340; fax (516) 794-5531.

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-2009-0792; 
Directorate Identifier 2009-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 have lengthened the 30-day comment period for proposed ADs that 
address MCAI originated by aviation authorities of other countries to 
provide adequate time for interested parties to submit comments. The 
comment period for these proposed ADs is now typically 45 days, which 
is consistent with the comment period for domestic transport ADs.
    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

    Transport Canada Civil Aviation, which is the aviation authority 
for Canada, has issued Canadian Airworthiness Directive CF-2009-09, 
dated March 9, 2009 (referred to after this as ``the MCAI''), to 
correct an unsafe condition for the specified products. The MCAI 
states:

    Bombardier Aerospace has completed a system safety review of the 
CL-600-2C10/CL600-2D15/CL-600-2D24 aircraft fuel system against the 
new fuel tank safety standards, introduced in Chapter 525 of the 
Airworthiness Manual through Notice of Proposed Amendment (NPA) 
2002-043. The identified non-compliances were assessed using 
Transport Canada Policy Letter No. 525-001 to determine if mandatory 
corrective action was required.
    The assessment showed that certain hydraulic system failure 
scenarios could lead to a rapid overheat in the hydraulic lines 
without giving flight crew sufficient time to react before the No. 1 
and No. 2 hydraulic system tubing inside the fuel tank reaches the 
fuel auto ignition temperature. This could result in a fuel tank 
explosion.
    To correct the unsafe condition, this [Canadian airworthiness] 
directive mandates the installation of thermal fuses in the No. 1 
and No. 2 hydraulic systems and the introduction of Fuel System 
Limitations (FSL) and Critical Design Configuration Control 
Limitations (CDCCL) associated with this design change.

    You may obtain further information by examining the MCAI in the AD 
docket.
    The FAA has examined the underlying safety issues involved in fuel 
tank explosions on several large transport airplanes, including the 
adequacy of existing regulations, the service history of airplanes 
subject to those regulations, and existing maintenance practices for 
fuel tank systems. As a result of those findings, we issued a 
regulation titled ``Transport Airplane Fuel Tank System Design Review, 
Flammability Reduction and Maintenance and Inspection Requirements'' 
(66 FR 23086, May 7, 2001). In addition to new airworthiness standards 
for transport airplanes and new maintenance requirements, this rule 
included Special Federal Aviation Regulation No. 88 (``SFAR 88,'' 
Amendment 21-78, and subsequent Amendments 21-82 and 21-83).
    Among other actions, SFAR 88 requires certain type design (i.e., 
type certificate (TC) and supplemental type certificate (STC)) holders 
to substantiate that their fuel tank systems can prevent ignition 
sources in the fuel tanks. This requirement applies to type design 
holders for large turbine-powered transport airplanes and for 
subsequent modifications to those airplanes. It requires them to 
perform design reviews and to develop design changes and maintenance 
procedures if their designs do not meet the new fuel tank safety 
standards. As explained in the preamble to the rule, we intended to 
adopt airworthiness directives to mandate any changes found necessary 
to address unsafe conditions identified as a result of these reviews.
    In evaluating these design reviews, we have established four 
criteria intended to define the unsafe conditions associated with fuel 
tank systems that require corrective actions. The percentage of 
operating time during which fuel tanks are exposed to flammable 
conditions is one of these criteria. The other three criteria address 
the failure types under evaluation: single failures, single failures in 
combination with a latent condition(s), and in-service failure 
experience. For all four criteria, the evaluations included 
consideration of previous actions taken that may mitigate the need for 
further action.

Relevant Service Information

    Bombardier has issued Service Bulletin 670BA-29-005, Revision A, 
dated January 29, 2009; Bombardier Temporary Revision 2-268, dated 
December 18, 2008, to Section 3, ``Fuel System Limitations,'' of Part 2 
of the

[[Page 49348]]

Bombardier CL-600-2C10, CL-600-2D15, and CL-600-2D24 Maintenance 
Requirements Manual; and Bombardier Temporary Revision 2-269, dated 
December 18, 2008, to Section 3, ``Fuel System Limitations,'' of Part 2 
of the Bombardier CL-600-2C10, CL-600-2D15, and CL-600-2D24 Maintenance 
Requirements Manual. 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.

Differences between this AD and the MCAI or Service Information

    We have reviewed the MCAI and related service information and, in 
general, agree with their substance. But we might have found it 
necessary to use different words from those in the MCAI to ensure the 
AD is clear for U.S. operators and is enforceable. In making these 
changes, we do not intend to differ substantively from the information 
provided in the MCAI and related service information.
    We might also have proposed different actions in this AD from those 
in the MCAI in order to follow FAA policies. Any such differences are 
highlighted in a NOTE within the proposed AD.

Costs of Compliance

    Based on the service information, we estimate that this proposed AD 
would affect about 334 products of U.S. registry. We also estimate that 
it would take about 45 work-hours per product to comply with the basic 
requirements of this proposed AD. The average labor rate is $80 per 
work-hour. Required parts would cost about $6,765 per product. Where 
the service information lists required parts costs that are covered 
under warranty, we have assumed that there will be no charge for these 
costs. As we do not control warranty coverage for affected parties, 
some parties may incur costs higher than estimated here. Based on these 
figures, we estimate the cost of the proposed AD on U.S. operators to 
be $3,461,910, or $10,365 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); 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket.

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]

0
2. The FAA amends Sec.  39.13 by adding the following new AD:

Bombardier Inc. (Formerly Canadair): Docket No. FAA-2009-0792; 
Directorate Identifier 2009-NM-057-AD.

Comments Due Date

    (a) We must receive comments by November 12, 2009.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Bombardier Model CL-600-2C10 (Regional 
Jet Series 700, 701, & 702), airplanes; certificated in any 
category, having serial numbers 10003 through 10267 inclusive; and 
Bombardier Model CL-600-2D15 (Regional Jet Series 705) and CL-600-
2D24 (Regional Jet Series 900), certificated in any category, having 
serial numbers 15001 through 15199 inclusive, 15202, and 15204.

    Note 1:  This AD requires revisions to certain operator 
maintenance documents to include new inspections. Compliance with 
these inspections is required by 14 CFR 91.403(c). For airplanes 
that have been previously modified, altered, or repaired in the 
areas addressed by these inspections, the operator may not be able 
to accomplish the inspections 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 (g) of this AD. The request should include a 
description of changes to the required inspections that will ensure 
the continued operational safety of the airplane.

Subject

    (d) Air Transport Association (ATA) of America Code 29: 
Hydraulic power.

Reason

    (e) The mandatory continuing airworthiness information (MCAI) 
states:

    Bombardier Aerospace has completed a system safety review of the 
CL-600-2C10/CL600-2D15/CL-600-2D24 aircraft fuel system against the 
new fuel tank safety standards, introduced in Chapter 525 of the 
Airworthiness Manual through Notice of Proposed Amendment (NPA) 
2002-043. The identified non-compliances were assessed using 
Transport Canada Policy Letter No. 525-001 to determine if mandatory 
corrective action was required.
    The assessment showed that certain hydraulic system failure 
scenarios could lead to a rapid overheat in the hydraulic lines 
without giving flight crew sufficient time to react before the No. 1 
and No. 2 hydraulic system tubing inside the fuel tank reaches the 
fuel auto ignition temperature. This could result in a fuel tank 
explosion.

[[Page 49349]]

    To correct the unsafe condition, this [Canadian airworthiness] 
directive mandates the installation of thermal fuses in the No. 1 
and No. 2 hydraulic systems and the introduction of Fuel System 
Limitations (FSL) and Critical Design Configuration Control 
Limitations (CDCCL) associated with this design change.

Actions and Compliance

    (f) Unless already done, do the following actions.
    (1) Within 6,000 flight hours after the effective date of this 
AD, modify the aircraft hydraulic system by installing thermal fuses 
according to the Accomplishment Instructions of Bombardier Service 
Bulletin 670BA-29-005, Revision A, dated January 29, 2009.
    (2) Before or concurrently with the actions required by 
paragraph (f)(1) of this AD, revise the Airworthiness Limitations 
Section (ALS) of the Instructions for Continued Airworthiness to 
incorporate the tasks identified in Table 1 of this AD as specified 
in Bombardier Temporary Revision (TR) 2-269, dated December 18, 
2008, to Section 3, ``Fuel Systems Limitations,'' of Part 2 of the 
Bombardier CL-600-2C10, CL-600-2D15, and CL-600-2D24 Maintenance 
Requirements Manual. The initial compliance time for the task is 
within 10,000 flight hours after doing the action required by 
paragraph (f)(1) of this AD, or within 60 days after the effective 
date of this AD, whichever occurs later, and the limitation task 
must be accomplished thereafter at the ``limiting interval'' 
specified in Bombardier TR 2-269, dated December 18, 2008, except as 
provided by paragraphs (f)(4) and (g)(1) of this AD.

                  Table 1--Fuel System Limitation Task
------------------------------------------------------------------------
                Task No.                         Task description
------------------------------------------------------------------------
29-30-00-603...........................  Hydraulic System No. 1 and No.
                                          2 Thermal Fuse: Discard the
                                          system No. 1 and No. 2 thermal
                                          fuse (Post Modsum 670T112042
                                          or SB 670BA-29-005).
------------------------------------------------------------------------

     (3) Before or concurrently with the actions required by 
paragraph (f)(1) of this AD, revise the ALS of the Instructions for 
Continued Airworthiness to incorporate the CDCCL data specified in 
Bombardier TR 2-268, dated December 18, 2008, to Section 3, ``Fuel 
System Limitations,'' of Part 2 of the Bombardier CL-600-2C10, CL-
600-2D15 and CL-600-2D24 Maintenance Requirements Manual.

    Note 2:  The actions required by paragraphs (f)(2) and (f)(3) of 
this AD may be done by inserting a copy of the TR into the 
maintenance requirements manual. When the TR has been included in 
the general revision of the maintenance program, the general 
revision may be inserted into the maintenance requirements manual, 
provided the relevant information in the general revision is 
identical to that in the TR, and the temporary revision may be 
removed.

    (4) After accomplishing the actions specified in paragraphs 
(f)(2) and (f)(3) of this AD, no alternative limitation tasks, 
limitation task intervals, or CDCCLs may be used unless the 
limitation task, limitation task interval, or CDCCL is approved as 
an alternative method of compliance (AMOC) in accordance with the 
procedures specified in paragraph (g)(1) of this AD.
    (5) Actions accomplished before the effective date of this AD in 
accordance with Bombardier Service Bulletin 670BA-29-005, dated 
December 18, 2008, are considered acceptable for compliance with the 
corresponding action specified in paragraph (f)(1) of this AD.

    Note 3:  Notwithstanding any other maintenance or operational 
requirements, components that have been identified as airworthy or 
installed on the affected airplanes before the revision of the 
airworthiness limitations section, as required by paragraphs (f)(1) 
and (f)(2) of this AD, do not need to be reworked in accordance with 
the CDCCLs. However, once the airworthiness limitations section has 
been revised, future maintenance actions on these components must be 
done in accordance with the CDCCLs.

FAA AD Differences

    Note 4:  This AD differs from the MCAI and/or service 
information as follows: No differences.

Other FAA AD Provisions

    (g) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, New 
York Aircraft Certification Office (ACO), FAA, has the authority to 
approve AMOCs for this AD, if requested using the procedures found 
in 14 CFR 39.19. Send information to ATTN: Christopher Alfano, 
Aerospace Engineer, Airframe and Propulsion Branch, ANE-171, FAA, 
New York Aircraft Certification Office, 1600 Stewart Avenue, Suite 
410, Westbury, New York 11590; telephone (516) 228-7340; fax (516) 
794-5531. Before using any approved AMOC on any airplane to which 
the AMOC applies, notify your principal maintenance inspector (PMI) 
or principal avionics inspector (PAI), as appropriate, or lacking a 
principal inspector, your local Flight Standards District Office. 
The AMOC approval letter must specifically reference this AD.
    (2) Airworthy Product: For any requirement in this AD to obtain 
corrective actions from a manufacturer or other source, use these 
actions if they are FAA-approved. Corrective actions are considered 
FAA-approved if they are approved by the State of Design Authority 
(or their delegated agent). You are required to assure the product 
is airworthy before it is returned to service.
    (3) Reporting Requirements: For any reporting requirement in 
this AD, under the provisions of the Paperwork Reduction Act, the 
Office of Management and Budget (OMB) has approved the information 
collection requirements and has assigned OMB Control Number 2120-
0056.

Related Information

    (h) Refer to MCAI Canadian Airworthiness Directive CF-2009-09, 
dated March 9, 2009; Bombardier Service Bulletin 670BA-29-005, 
Revision A, dated January 29, 2009; Bombardier TR 2-268, dated 
December 18, 2008, to Section 3, ``Fuel System Limitations,'' of 
Part 2 of the Bombardier CL-600-2C10, CL-600-2D15, and CL-600-2D24 
Maintenance Requirements Manual; and Bombardier TR 2-269, dated 
December 18, 2008, to Section 3, ``Fuel System Limitations,'' of 
Part 2 of the Bombardier CL-600-2C10, CL-600-2D15, and CL-600-2D24 
Maintenance Requirements Manual; for related information.

    Issued in Renton, Washington, on September 18, 2009.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E9-23296 Filed 9-25-09; 8:45 am]

BILLING CODE 4910-13-P
