[Federal Register Volume 71, Number 147 (Tuesday, August 1, 2006)]
[Rules and Regulations]
[Pages 43352-43354]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-12305]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-25444; Directorate Identifier 2006-SW-18-AD; 
Amendment 39-14700; AD 2006-15-19]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) for 
the Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. 
This action requires, before further flight, replacing a certain main 
gearbox (MGB) upper main housing assembly (housing assembly) that has 
2700 or more hours time-in-service (TIS) with an airworthy part. This 
action also requires, before further flight, revising the Airworthiness 
Limitations section (ALS) of the maintenance manual by establishing a 
new retirement life for the MGB housing assembly of 2700 hours TIS. 
This amendment is prompted by testing of the MGB housing assembly that 
resulted in premature fatigue failure due to a manufacturing process 
creating an oxide skin defect in the housing. The actions specified in 
this AD are intended to prevent fatigue failure of the MGB housing, 
loss of MGB lube oil, loss of main and tail rotor drive, and subsequent 
loss of control of the helicopter.

DATES: Effective August 16, 2006.
    Comments for inclusion in the Rules Docket must be received on or 
before October 2, 2006.

ADDRESSES: Use one of the following addresses to submit comments on 
this AD:
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically;
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically;
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590;
     Fax: (202) 493-2251; or
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Examining the Docket

    You may examine the docket that contains the AD, any comments, and 
other information on the Internet at http://dms.dot.gov, or in person 
at the Docket Management System (DMS) Docket Offices between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays. The Docket 
Office (telephone (800) 647-5227) is located on the plaza level of the 
Department of Transportation Nassif Building at the street address 
stated in the ADDRESSES section. Comments will be available in the AD 
docket shortly after the DMS receives them.

FOR FURTHER INFORMATION CONTACT: Wayne Gaulzetti, Aviation Safety 
Engineer, Boston Aircraft Certification Office, 12 New England 
Executive Park, Burlington, MA 01803, telephone (781) 238-7156, fax 
(781) 238-7170.

SUPPLEMENTARY INFORMATION: This amendment adopts a new AD for the 
Sikorsky Model S-92A helicopters. This action requires, before further 
flight, replacing a certain MGB housing assembly that has 2700 or more 
hours TIS with an airworthy MGB housing assembly with less than 2700 
hours TIS. Also, this action requires, before further flight, revising 
the ALS of the

[[Page 43353]]

maintenance manual by establishing a new retirement life for the MGB 
housing assembly of 2700 or more hours TIS. This amendment is prompted 
by component fatigue testing of the MGB housing assembly that resulted 
in premature fatigue failure due to a manufacturing process creating an 
oxide skin defect in the housing. This condition, if not corrected, 
could result in fatigue failure of the MGB housing, loss of MGB lube 
oil, loss of main and tail rotor drive, and subsequent loss of control 
of the helicopter.
    This unsafe condition is likely to exist or develop on other 
helicopters of the same type design. Therefore, this AD is being issued 
to prevent fatigue failure of the MGB housing, loss of MGB lube oil, 
loss of main and tail rotor drive, and subsequent loss of control of 
the helicopter. This AD requires, before further flight, replacing any 
MGB housing assembly, part number 92351-15110-042, that has 2700 or 
more hours TIS with an airworthy part. This AD also requires, before 
further flight, revising the ALS of the maintenance manual by 
establishing a new retirement life for the MGB housing assembly of 2700 
hours TIS.
    The short compliance time involved is required because the 
previously described critical unsafe condition can adversely affect the 
controllability or structural integrity of the helicopter. Some 
operators may have already exceeded the 2700 hours TIS. Therefore, 
replacing each MGB housing assembly that has 2700 or more hours TIS 
with an airworthy MGB housing assembly is required before further 
flight and this AD must be issued immediately.
    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.
    We estimate that this AD will affect 13 helicopters, and will take 
about 20 work hours to replace the MGB housing assembly at an average 
labor rate of $80 per work hour. Required parts will cost about 
$152,000 per helicopter. Based on these figures, we estimate the total 
cost impact of the AD on U.S. operators to be $1,996,800.

Comments Invited

    This AD is a final rule that involves requirements that affect 
flight safety and was not preceded by notice and an opportunity for 
public comment; however, we invite you to submit any written data, 
views, or arguments regarding this AD. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2006-25444; 
Directorate Identifier 2006-18-SW-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the AD. We will consider 
all comments received by the closing date and may amend the AD in light 
of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this AD. Using the search function of our docket 
Web site, you can find and read the comments to any of our dockets, 
including the name of the individual who sent the comment. You may 
review the DOT's complete Privacy Act Statement in the Federal Register 
published on April 11, 2000 (65 FR 19477-78), or you may visit http://dms.dot.gov.

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 DMS 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, 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:

2006-15-19 Sikorsky Aircraft Corporation: Amendment 39-14700. Docket 
No. FAA-2006-25444; Directorate Identifier 2006-SW-18-AD.

Applicability

    Model S-92A helicopter, with main gearbox (MGB) upper main 
housing assembly (housing assembly), part number 92351-15110-042, 
installed, certificated in any category.

Compliance

    Required as indicated, unless accomplished previously.
    To prevent fatigue failure of the MGB housing, loss of MGB lube 
oil, loss of main and tail rotor drive, and subsequent loss of 
control of the helicopter, do the following:
    (a) Before further flight, replace each MGB housing with 2700 or 
more hours time-in-service (TIS) with an airworthy MGB housing with 
less than 2700 hours TIS.
    (b) This AD revises the Airworthiness Limitations section of the 
maintenance manual by establishing a new retirement life for the MGB 
housing assembly of 2700 hours TIS.
    (c) 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, FAA, 
ATTN: Wayne Gaulzetti, Aviation Safety Engineer, 12 New England 
Executive Park, Burlington, MA 01803, telephone (781) 238-7156, fax 
(781) 238-7170, for information about previously approved 
alternative methods of compliance.
    (d) This amendment becomes effective on August 16, 2006.


[[Page 43354]]


    Issued in Fort Worth, Texas, on July 26, 2006.
David A. Downey,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. E6-12305 Filed 7-31-06; 8:45 am]
BILLING CODE 4910-13-P