Document ID: FAA-2009-0134-0002
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Saab AB, Saab Aerosystems Model SAAB 340A (SAAB/SF340A) and SAAB 340B Airplanes
Posted Date: 2009-02-18T05:00Z

[Federal Register: February 18, 2009 (Volume 74, Number 31)]
[Proposed Rules]
[Page 7568-7570]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr18fe09-15]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2009-0134; Directorate Identifier 2008-NM-162-AD]
RIN 2120-AA64

Airworthiness Directives; Saab AB, Saab Aerosystems Model SAAB
340A (SAAB/SF340A) and SAAB 340B 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:

    Two cases of main hydraulic accumulator failure have been
reported, one of which was caused by corrosion. Investigation has
shown that a severe failure can occur to any of the four hydraulic
accumulators which are installed in the hydraulic compartment.
Either one of the two end parts on the accumulator may depart from
the pressure vessel due to corrosion. This condition, if not
corrected, is likely to degrade the functionality of the hydraulic
system, possibly resulting in degradation or total loss of control
of the landing gear, flap actuation and brakes. A severe failure
during flight may even result in debris penetrating and exiting the
fuselage outer skin. When such a failure occurs while the aircraft
is on the ground, as in the two reported cases, this may cause
severe damage to the fuselage and result in injuries to persons
nearby.

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 March 20, 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 W12-40, 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
Saab Aircraft AB, SAAB Aerosystems, SE-581 88, Link[ouml]ping, Sweden;
telephone +46 13 18 5591; fax +46 13 18 4874; e-mail
saab2000.techsupport@saabgroup.com; Internet http://www.saabgroup.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

[[Page 7569]]

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: Shahram Daneshmandi, Aerospace
Engineer, International Branch, ANM-116, Transport Airplane
Directorate, FAA, 1601 Lind Avenue, SW., Renton, Washington 98057-3356;
telephone (425) 227-1112; fax (425) 227-1149.

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-2009-0134;
Directorate Identifier 2008-NM-162-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

    The European Aviation Safety Agency (EASA), which is the Technical
Agent for the Member States of the European Community, has issued EASA
Airworthiness Directive 2008-0146, dated August 1, 2008 (referred to
after this as ``the MCAI''), to correct an unsafe condition for the
specified products. The MCAI states:

    Two cases of main hydraulic accumulator failure have been
reported, one of which was caused by corrosion. Investigation has
shown that a severe failure can occur to any of the four hydraulic
accumulators which are installed in the hydraulic compartment.
Either one of the two end parts on the accumulator may depart from
the pressure vessel due to corrosion. This condition, if not
corrected, is likely to degrade the functionality of the hydraulic
system, possibly resulting in degradation or total loss of control
of the landing gear, flap actuation and brakes. A severe failure
during flight may even result in debris penetrating and exiting the
fuselage outer skin. When such a failure occurs while the aircraft
is on the ground, as in the two reported cases, this may cause
severe damage to the fuselage and result in injuries to persons
nearby.
    To address and correct the unsafe condition, a modified
hydraulic accumulator has been developed, which is sealed between
the barrel and the screw cap and between the screw cap and the end
cap.
    For the reasons described above, this EASA AD requires the
replacement of the affected hydraulic accumulators P/N (part number)
08 8423 001 1 and P/N 08 8423 030 1, as identified in Saab SB 340-
29-023, with a modified hydraulic accumulator.

You may obtain further information by examining the MCAI in the AD
docket.

Relevant Service Information

    Saab has issued Service Bulletin 340-29-023, dated June 10, 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 141 products of U.S. registry. We also estimate that it
would take 8 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 $3,582 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 $595,302, or $4,222 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,

[[Page 7570]]

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:

Saab AB, Saab Aerosystems: Docket No. FAA-2009-0134; Directorate
Identifier 2008-NM-162-AD.

Comments Due Date

    (a) We must receive comments by March 20, 2009.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Saab AB, Saab Aerosystems Model SAAB 340A
(SAAB/SF340A) and SAAB 340B airplanes, all serial numbers,
certificated in any category; on which hydraulic accumulators with
part number (P/N) 08 8423 001 1 or P/N 08 8423 030 1 are installed,
except accumulators with serial numbers listed in paragraph 3.B. of
Saab Service Bulletin 340-29-023, dated June 10, 2008.

Subject

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

Reason

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

    Two cases of main hydraulic accumulator failure have been
reported, one of which was caused by corrosion. Investigation has
shown that a severe failure can occur to any of the four hydraulic
accumulators which are installed in the hydraulic compartment.
Either one of the two end parts on the accumulator may depart from
the pressure vessel due to corrosion. This condition, if not
corrected, is likely to degrade the functionality of the hydraulic
system, possibly resulting in degradation or total loss of control
of the landing gear, flap actuation and brakes. A severe failure
during flight may even result in debris penetrating and exiting the
fuselage outer skin. When such a failure occurs while the aircraft
is on the ground, as in the two reported cases, this may cause
severe damage to the fuselage and result in injuries to persons
nearby.
    To address and correct the unsafe condition, a modified
hydraulic accumulator has been developed, which is sealed between
the barrel and the screw cap and between the screw cap and the end
cap.
    For the reasons described above, [the MCAI] requires the
replacement of the affected hydraulic accumulators P/N (part number)
08 8423 001 1 and P/N 08 8423 030 1, as identified in Saab SB 340-
29-023, with a modified hydraulic accumulator.

Actions and Compliance

    (f) Unless already done, replace the accumulator at the
applicable time specified in paragraph (f)(1) or (f)(2) of this AD
in accordance with the instructions of Saab Service Bulletin 340-29-
023, dated June 10, 2008.
    (1) For airplanes on which the manufacturing date of the
hydraulic accumulator is June 2000 or earlier: Replace the
accumulator with a new or modified accumulator within 24 months
after the effective date of this AD.
    (2) For airplanes on which the manufacturing date of the
accumulator is July 2000 or later: Replace the accumulator with a
new or modified accumulator within 10 years after the manufacturing
date or within 24 months after the effective date of this AD,
whichever occurs later.
    (3) As of 24 months after the effective date of this AD, no
person may install a hydraulic accumulator, P/N 08 8423 001 1 or P/N
08 8423 030 1 on any airplane, except accumulators with serial
numbers listed in paragraph 3.B. of Saab Service Bulletin 340-29-
023, dated June 10, 2008.

FAA AD Differences

    Note 1: 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,
International Branch, ANM-116, 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: Shahram Daneshmandi, Aerospace
Engineer, International Branch, ANM-116, Transport Airplane
Directorate, FAA, 1601 Lind Avenue, SW., Renton, Washington 98057-
3356; telephone (425) 227-1112; fax (425) 227-1149. 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.
    (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 European Aviation Safety Agency Airworthiness
Directive 2008-0146, dated August 1, 2008, and Saab Service Bulletin
340-29-023, dated June 10, 2008, for related information.

    Issued in Renton, Washington, on January 30, 2009.
Stephen P. Boyd,
Assistant Manager, Transport Airplane Directorate, Aircraft
Certification Service.
[FR Doc. E9-3398 Filed 2-17-09; 8:45 am]

BILLING CODE 4910-13-P