
[Federal Register: May 17, 2010 (Volume 75, Number 94)]
[Rules and Regulations]
[Page 27409-27411]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr17my10-5]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0060; Directorate Identifier 2010-SW-06-AD;
Amendment 39-16282; AD 2010-10-03]
RIN 2120-AA64


Airworthiness Directives; Sikorsky Aircraft Corporation
(Sikorsky) Model S-92A Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) for
the Sikorsky Model S-92A helicopters. The

[[Page 27410]]

AD requires replacing the main gearbox (MGB) filter bowl assembly with
a two-piece MGB filter bowl assembly and replacing the existing
mounting studs. The AD also requires inspecting the MGB lube system
filters, the housing, the housing threads, and the lockring counterbore
and repairing or replacing them as necessary. This amendment is
prompted by tests indicating that an existing MGB filter bowl assembly
can fail under certain loading conditions including those associated
with a damaged MGB filter or mounting stud resulting from high
frequency maintenance tasks. Testing of the improved MGB filter bowl
assembly demonstrates a significant increase in strength and durability
over the existing filter bowl. The actions specified by this AD are
intended to prevent failure of the MGB filter bowl assembly due to
failure of the mounting studs or the filter bowl, loss of oil from the
MGB, failure of the MGB, and subsequent loss of control of the
helicopter.

DATES: Effective June 21, 2010.
    The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of June 21, 2010.

ADDRESSES: You may get the service information identified in this AD
from Sikorsky Aircraft Corporation, Attn: Manager, Commercial Technical
Support, mailstop s581a, 6900 Main Street, Stratford, CT, telephone
(203) 383-4866, e-mail address tsslibrary@sikorsky.com, or at http://
www.sikorsky.com.
    Examining the Docket: You may examine the docket that contains this
AD, any comments, and other information on the Internet at http://
www.regulations.gov or at the Docket Operations office, West Building
Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington,
DC.

FOR FURTHER INFORMATION CONTACT: Kirk Gustafson, Aviation Safety
Engineer, Boston Aircraft Certification Office, Engine and Propeller
Directorate, FAA, 12 New England Executive Park, Burlington, MA 01803,
telephone (781) 238-7190, fax (781) 238-7170.

SUPPLEMENTARY INFORMATION: A proposal to amend 14 CFR part 39 to
include an AD for the specified model helicopters was published in the
Federal Register on January 27, 2010 (75 FR 4308). That action proposed
to require replacing the MGB filter bowl assembly with a two-piece MGB
filter bowl assembly and replacing the existing mounting studs. That
action also proposed inspecting the MGB lube system filters, the
housing, the housing threads, and the lockring counterbore and
repairing and replacing them as necessary.
    Interested persons have been afforded an opportunity to participate
in the making of this amendment. No comments were received on the
proposal or the FAA's determination of the cost to the public. The FAA
has determined that air safety and the public interest require the
adoption of the rule as proposed.
    The FAA estimates that this AD will affect 22 helicopters of U.S.
registry. The required actions will take about 6 hours to inspect the
existing filter bowl assembly and replace the MGB lube system filters,
the mounting studs, and to install an improved filter bowl assembly at
an average labor rate of $85 per work hour. Required parts will cost
about $3,257 per helicopter. Based on these figures, the total cost
impact of the AD on U.S. operators is $82,214.

Regulatory Findings

    We have determined that this AD will not have federalism
implications under Executive Order 13132. This AD will 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 that the 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 an economic evaluation of the estimated costs to comply
with this AD. See the AD docket to examine the economic evaluation.

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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.

Adoption of the Amendment

0
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends part 39 of
the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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. Section 39.13 is amended by adding a new airworthiness directive to
read as follows:

2010-10-03 Sikorsky Aircraft Corporation: Amendment 39-16282. Docket
No. FAA-2010-0060; Directorate Identifier 2010-SW-06-AD.
    Applicability: Model S-92A helicopters, with main gearbox (MGB)
filter bowl assembly, part number (P/N) 92351-15802-101, installed,
certificated in any category.
    Compliance: Required as indicated, unless done previously.
    To prevent failure of the MGB filter bowl assembly due to
failure of the mounting studs or the filter bowl, loss of oil from
the MGB, failure of the MGB, and subsequent loss of control of the
helicopter, do the following:
    (a) Within 60 days:
    (1) Remove the MGB filter bowl assembly by following the
Accomplishment Instructions, paragraphs 3.A. (1) through 3.A.(5), of
Sikorsky Alert Service Bulletin No. 92-63-022A, dated December 18,
2009 (ASB).
    (2) Remove the primary filter element, P/N 70351-38801-102, from
the MGB lube system filter and visually inspect it for damage as
depicted in Figures 1, 2, and 3 of the ASB. If the primary filter
element has ``wavy'' pleats, internal buckling, or indented dimples,
before further flight, replace it with an airworthy filter element.
    (3) Visually inspect the secondary filter element, P/N 70351-
38801-103, for damage as depicted in Figures 4 and 5 of the ASB. If
the secondary filter element has ``wavy'' pleats or an elongated
cup, before further flight, replace it with an airworthy filter
element.
    (4) Replace the MGB lube system filter assembly mounting studs:

[[Page 27411]]

    (i) Remove the studs by following the Accomplishment
Instructions, paragraphs 3.B.(1) through 3.B.(4) of the ASB.
Visually inspect the tapped holes for any damage to the threads.
Serrations on the entire counter bore (360 degrees) are acceptable.
Serrations in the housing must be intact, and mating serrations on
the lock ring must line up with serrations on the housing. Visually
inspect the housing to determine that the housing threads are free
from damage and corrosion. Visually inspect housing lockring
counterbore to determine if the housing is airworthy.
    (ii) If you find damage or corrosion to the housing threads, the
housing, or the lockring counterbore, stop work and contact Kirk
Gustafson, Aviation Safety Engineer, Boston Aircraft Certification
Office, Engine and Propeller Directorate, FAA, 12 New England
Executive Park, Burlington, MA 01803, telephone (781) 238-7190, fax
(781) 238-7170.
    (iii) If you do not find damage to the housing threads, the
housing, or the lockring counterbore that requires repair, replace
the mounting studs by following the Accomplishment Instructions,
paragraphs 3.B.(7) through 3.B.(15) of the ASB.
    (5) Install an airworthy, two-piece MGB filter bowl assembly
modification kit, P/N 92070-35005-011, as depicted in Figures 8 and
9 of the ASB and by following the Accomplishment Instructions,
paragraphs 3.C.(1) through 3.C.(20), of the ASB.
    (b) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Contact the Manager, Boston Aircraft Certification Office, Attn:
Kirk Gustafson, Aviation Safety Engineer, Boston Aircraft
Certification Office, Engine and Propeller Directorate, FAA, 12 New
England Executive Park, Burlington, MA 01803, telephone (781) 238-
7190, fax (781) 238-7170, for information about previously approved
alternative methods of compliance.
    (c) The Joint Aircraft System/Component (JASC) Code is 6320:
Main Rotor Gearbox.
    (d) Inspecting and replacing the MGB filter bowl assembly shall
be done by following the specified portions of Sikorsky Alert
Service Bulletin No. 92-63-022A, dated December 18, 2009. The
Director of the Federal Register approved this incorporation by
reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.
Copies may be obtained from Sikorsky Aircraft Corporation, Attn:
Manager, Commercial Technical Support, mailstop s581a, 6900 Main
Street, Stratford, CT, telephone (203) 383-4866, e-mail address
tsslibrary@sikorsky.com, or at http://www.sikorsky.com. Copies may
be inspected at the FAA, Office of the Regional Counsel, Southwest
Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas, or at the
National Archives and Records Administration (NARA). For information
on the availability of this material at NARA, call 202-741-6030, or
go to: http://www.archives.gov/federal_register/code_of_federal_
regulations/ibr_locations.html.
    (e) This amendment becomes effective on June 21, 2010.

    Issued in Fort Worth, Texas, on April 27, 2010.
Mark R. Schilling,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2010-11069 Filed 5-14-10; 8:45 am]
BILLING CODE 4910-13-P

