[Federal Register: May 23, 2008 (Volume 73, Number 101)]
[Proposed Rules]
[Page 30005-30007]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr23my08-13]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2008-0586; Directorate Identifier 2008-NM-043-AD]
RIN 2120-AA64
Airworthiness Directives; Bombardier Model DHC-8-400, -401 and -
402 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:
There was one reported failure of the elevator centering torsion
spring. Investigation revealed that the tangs on the torsion spring
had been bent due to difficulty encountered during installation of
the elevator centering torsion spring on the horizontal stabilizer
torque tube. The bending of the tangs on the torsion spring would
degrade its durability and could lead to premature failure of the
elevator centering torsion spring. A control rod disconnect between
the elevator aft quadrant and the elevator Power Control Unit input
torque tube, in combination with the loss or reduction in elevator
centering capability, could result in a significant reduction in
aircraft pitch control.
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 June 23, 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: Fabio Buttitta, Aerospace Engineer,
Systems and Flight Test Branch, ANE-172, FAA, New York Aircraft
Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, New
York 11590; telephone (516) 228-7303; 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-2008-0586;
Directorate Identifier 2008-NM-043-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-
2008-05R1, dated February 27, 2008. (referred to after this as ``the
MCAI''), to correct an unsafe condition for the specified products. The
MCAI states:
There was one reported failure of the elevator centering torsion
spring. Investigation revealed that the tangs on the
[[Page 30006]]
torsion spring had been bent due to difficulty encountered during
installation of the elevator centering torsion spring on the
horizontal stabilizer torque tube. The bending of the tangs on the
torsion spring would degrade its durability and could lead to
premature failure of the elevator centering torsion spring. A
control rod disconnect between the elevator aft quadrant and the
elevator Power Control Unit input torque tube, in combination with
the loss or reduction in elevator centering capability, could result
in a significant reduction in aircraft pitch control.
Corrective actions include replacing all elevator centering torsion
springs with new elevator centering torsion springs. You may obtain
further information by examining the MCAI in the AD docket.
Relevant Service Information
Bombardier has issued Service Bulletin 84-27-31, dated April 27,
2007. 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 42 products of U.S. registry. We also estimate that
it would take about 7 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 $1,746 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 $96,852, or $2,306 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 de Havilland, Inc.): Docket No. FAA-2008-
0586; Directorate Identifier 2008-NM-043-AD.
Comments Due Date
(a) We must receive comments by June 23, 2008.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Bombardier Model DHC-8-400, -401 and -402
airplanes, certificated in any category, having serial numbers 4001,
4003, 4004, and 4006 through 4081.
Subject
(d) Air Transport Association (ATA) of America Code 27: Flight
Controls.
Reason
(e) The mandatory continuing airworthiness information (MCAI)
states:
There was one reported failure of the elevator centering torsion
spring. Investigation revealed that the tangs on the torsion spring
had been bent due to difficulty encountered during installation of
the elevator centering torsion spring on the horizontal stabilizer
torque tube. The bending of the tangs on the torsion spring would
degrade its durability and could lead to premature failure of the
elevator centering torsion spring. A control rod disconnect between
the elevator aft quadrant and the elevator Power Control Unit input
torque tube, in combination with the loss or reduction in elevator
centering capability, could result in a significant reduction in
aircraft pitch control.
Corrective actions include replacing all elevator centering
torsion springs with new elevator centering torsion springs.
Actions and Compliance
(f) Prior to the accumulation of 22,000 total flight hours, or
within 5,000 flight hours after the effective date of this AD,
whichever comes later, unless already done: Replace all
[[Page 30007]]
elevator centering torsion springs with new elevator centering
torsion springs by incorporating Modsum 4-113482, in accordance with
Bombardier Service Bulletin 84-27-31, dated April 27, 2007.
FAA AD Differences
Note: 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: Fabio Buttitta, Aerospace
Engineer, Systems and Flight Test Branch, ANE-172, FAA, New York
ACO, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590;
telephone (516) 228-7303; 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-2008-05R1,
dated February 27, 2008, and Bombardier Service Bulletin 84-27-31,
dated April 27, 2007, for related information.
Issued in Renton, Washington, on May 8, 2008.
Michael J. Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E8-11566 Filed 5-22-08; 8:45 am]
BILLING CODE 4910-13-P