FR Doc E8-19167

[Federal Register: August 19, 2008 (Volume 73, Number 161)]
[Proposed Rules]
[Page 48312-48314]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr19au08-28]

[[Page 48312]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0888; Directorate Identifier 2008-NM-084-AD]
RIN 2120-AA64

Airworthiness Directives; Bombardier Model CL-600-2B19 (Regional
Jet Series 100 & 440) 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-600-2B19 aircraft fuel system against new fuel tank safety
standards, * * *.
This assessment showed that there is insufficient electrical
bonding for lightning protection at certain locations inside the
fuel tanks. In addition, the assessment also revealed that existing
bonding jumpers across self-bonded couplings are not required.
Insufficient electrical bonding, if not corrected, could result in
arcing and potential ignition source inside the fuel tank during
lightning strikes and consequent 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 September 18,
2008.

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 W12-40, 1200 New
Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., Monday
through Friday, except Federal holidays.

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: Mazdak Hobbi, 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) 228-7330; 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-2008-0888;
Directorate Identifier 2008-NM-084-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

Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued Canadian Airworthiness Directive CF-
2007-34, dated December 21, 2007 (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-600-2B19 aircraft fuel system against 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 is required.
This assessment showed that there is insufficient electrical
bonding for lightning protection at certain locations inside the
fuel tanks. In addition, the assessment also revealed that existing
bonding jumpers across self-bonded couplings are not required.
Insufficient electrical bonding, if not corrected, could result in
arcing and potential ignition source inside the fuel tank during
lightning strikes and consequent fuel tank explosion.
To correct the unsafe condition, this directive mandates the
modification of certain bonding jumpers inside the fuel tanks.

Corrective actions include, for certain airplanes, a general visual
inspection to determine if the modification has been done on both sides
of the airplane. 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:

[[Page 48313]]

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.
We have determined that the actions identified in this AD are
necessary to reduce the potential of ignition sources inside fuel
tanks, which, in combination with flammable fuel vapors, could result
in fuel tank explosions and consequent loss of the airplane.

Relevant Service Information

Bombardier has issued Service Bulletin 601R-28-055, Revision E,
dated March 17, 2008. 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 686 products of U.S. registry. We also estimate that
it would take about 18 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 $0 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 $987,840, or $1,440 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, 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 AD:

Bombardier, Inc. (Formerly Canadair): Docket No. FAA-2008-0888;
Directorate Identifier 2008-NM-084-AD.

Comments Due Date

(a) We must receive comments by September 18, 2008.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Bombardier Model CL-600-2B19 (Regional
Jet Series 100 & 440) airplanes, serial numbers 7003 through 7067,
and 7069 through 7929, certificated in any category.

Subject

(d) Air Transport Association (ATA) of America Code 28: Fuel.

Reason

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

Corrective actions include, for certain airplanes, a general visual
inspection to determine if the modification has been done on both
sides of the airplane.

Actions and Compliance

(f) Unless already done: Within 5,000 flight hours after the
effective date of this AD, do the following actions.

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(1) For airplanes on which none of the Bombardier service
bulletins identified in Table 1 of this AD have been incorporated as
of the effective date of this AD: Modify the fuel tank bonding
jumpers inside the wing and center fuel tanks in accordance with
Part A of the Accomplishment Instructions of Bombardier Service
Bulletin 601R-28-055, Revision E, dated March 17, 2008.

Table 1--Service Bulletins
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Bombardier Service Bulletin Revision Date
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601R-28-055.............................. Original.................... May 4, 2004.
601R-28-055.............................. A........................... February 14, 2005.
601R-28-055.............................. B........................... September 14, 2005.
601R-28-055.............................. C........................... January 9, 2006.
601R-28-055.............................. D........................... July 17, 2006.
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(2) For airplanes on which any Bombardier service bulletin
identified in Table 1 of this AD has been incorporated as of the
effective date of this AD: Do a general visual inspection of the
inside of the wing and center fuel tanks to determine if the actions
in Part A of the Accomplishment Instructions of Bombardier Service
Bulletin 601R-28-055, Revision E, dated March 17, 2008, have been
done on both sides of the airplane. If Part A of the service
bulletin has not been done on either side of the airplane, before
further flight, do the actions specified in Part A of the
Accomplishment Instructions of Bombardier Service Bulletin 601R-28-
055, Revision E, dated March 17, 2008, for the side of the airplane
on which Part A of the service bulletin has not been done.

FAA AD Differences

Note: This AD differs from the MCAI and/or service information
as follows:
(1) The Accomplishment Instructions of Bombardier Service
Bulletin 601R-28-055, Revision E, dated March 17, 2008, do not
specify corrective actions if Revision D, dated July 17, 2006, of
the service bulletin was incorporated. This AD refers to
incorporation of Revision E of the service bulletin for the actions
specified in paragraph (f)(2) of this AD. Revision E specifies
inspecting to determine if the modification is done on both sides of
the airplane.
(2) The MCAI specifies that the modification must be done on all
airplanes in accordance with Bombardier Service Bulletin 601R-28-
055, Revision D, dated July 17, 2006, and that accomplishing the
original issue, dated May 4, 2004; Revision A, dated February 14,
2005; and Revision B, dated September 14, 2005; of the service
bulletin does not satisfy the requirements. This AD requires doing
the modification on airplanes on which Revision D or any earlier
issue of the service bulletin has not been done. For airplanes on
which Revision D or any earlier issue of the service bulletin has
been done, this AD requires inspecting to determine if the
modification is done on both sides of the airplane and modifying the
airplane if the modification was not done on both sides.

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, 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: Mazdak Hobbi, 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) 228-7330; fax (516) 794-
5531. Before using any approved AMOC on any airplane to which the
AMOC applies, notify your appropriate principal inspector (PI) in
the FAA Flight Standards District Office (FSDO), or lacking a PI,
your local FSDO.
(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-2007-34,
dated December 21, 2007; and Bombardier Service Bulletin 601R-28-
055, Revision E, dated March 17, 2008; for related information.

Issued in Renton, Washington, on August 6, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E8-19167 Filed 8-18-08; 8:45 am]

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