[Federal Register Volume 75, Number 94 (Monday, May 17, 2010)]
[Rules and Regulations]
[Pages 27409-27411]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-11069]


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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 [email protected], 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 
[email protected], 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