DEPARTMENT OF TRANSPORTATION
FEDERAL AVIATION ADMINISTRATION
14 CFR Part 39
[Docket No. FAA-2010-0699; Directorate Identifier 2009-NM-236-AD]
RIN 2120-AA64
AIRWORTHINESS DIRECTIVES; Viking Air Limited (Type Certificate Previously
Held by Bombardier, Inc.) Model DHC-7 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:
Viking Air Limited has completed a system safety review of the aircraft
fuel system against 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 then assessed using
Transport Canada Policy Letter No. 525-001, to determine if mandatory
corrective action is required.
The assessment showed that supplemental maintenance tasks would be
required to prevent potential ignition sources within the fuel system,
which 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 September 7, 2010.
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.
For service information identified in this proposed AD, contact Viking Air
Limited, 9574 Hampden Road, Sidney, British Columbia V8L 8V5, Canada;
telephone 250-656-7227; fax 250-656-0673; e-mail
technical.publications@vikingair.com; Internet http:// www.vikingair.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.
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: Richard Fiesel, Aerospace Engineer, Air-
frame and Mechanical Systems Branch, ANE-171, FAA, New York Aircraft
Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, New York
11590; telephone (516) 228-7304; 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-2010-0699; Directorate
Identifier 2009-NM-236-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
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.
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.
Transport Canada Civil Aviation (TCCA), which is the aviation authority
for Canada, has issued Canadian Airworthiness Directive CF-2009-15, dated
April 17, 2009 (referred to after this as "the MCAI"), to correct an
unsafe condition for the specified products. The MCAI states:
Viking Air Limited has completed a system safety review of the aircraft
fuel system against 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 then assessed using
Transport Canada Policy Letter No. 525-001, to determine if mandatory
corrective action is required.
The assessment showed that supplemental maintenance tasks would be
required to prevent potential ignition sources within the fuel system,
which could result in a fuel tank explosion. Viking Air Limited has
revised Chapter 5 of the DHC-7 Maintenance Manual, PSM 1-7-2, to introduce
the required maintenance tasks.
The corrective action is revising the Airworthiness Limitations Section of
the Instructions for Continued Airworthiness to incorporate new
limitations for fuel tank systems. You may obtain further information by
examining the MCAI in the AD docket.
RELEVANT SERVICE INFORMATION
Viking Air Limited has issued Temporary Revisions 5-106, 5-107, 5-108, 5
-109, 5-110, 5-111, 5-112, and 5-113, all dated December 15, 2008, to the
Viking DHC-7 Dash 7 Maintenance Manual, PSM-1-7-2, Chapter 5. 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 11 products 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. The average labor rate is $85 per work-hour. Based on
these figures, we estimate the cost of the proposed AD on U.S. operators
to be $935, 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 Pro-
cedures (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]
2. The FAA amends Sec. 39.13 by adding the following new AD: