

[Federal Register: August 21, 2007 (Volume 72, Number 161)]
[Rules and Regulations]               
[Page 46553-46555]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr21au07-7]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28971; Directorate Identifier 2007-SW-32-AD; 
Amendment 39-15163; AD 2007-17-05]
RIN 2120-AA64

 
Airworthiness Directives; Sikorsky Aircraft Corporation Model 
S92-A 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 
Sikorsky Aircraft Corporation (Sikorsky) Model S92-A helicopters. This 
action requires, within a specified time, borescope inspecting a 
certain part-numbered tail rotor pitch change shaft and bearing 
assembly (shaft and bearing assembly) and also inspecting after any 
installation. This amendment is prompted by an incident involving 
failure of a shaft and bearing assembly and servo clevis shaft 
resulting in loss of tail rotor control. The actions specified in this 
AD are intended to prevent failure of a shaft and bearing assembly, 
loss of tail rotor pitch and yaw control, and subsequent loss of 
control of a helicopter.

DATES: Effective August 21, 2007.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of August 21, 2007.
    Comments for inclusion in the Rules Docket must be received on or 
before October 22, 2007.

[[Page 46554]]


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: 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: Deliver to the ``Mail'' address between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays; or
     Fax: 202-493-2251.
    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, Connecticut, 
phone (203) 383-4866, e-mail address tsslibrary@sikorsky.com.
    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 Operations office between 9 

a.m. and 5 p.m., Monday through Friday, except Federal holidays. The 
Docket Operations office (telephone (800) 647-5527) is located in Room 
W12-140 on the ground floor of the West 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 Sikorsky 
Model S92-A helicopters. This action requires, within a specified time, 
borescope inspecting a certain part-numbered shaft and bearing assembly 
and also inspecting after any installation. This amendment is prompted 
by an incident involving failure of a shaft and bearing assembly and 
servo clevis shaft resulting in loss of tail rotor control. This 
condition, if not detected, could result in loss of tail rotor pitch 
and yaw control and subsequent loss of control of a helicopter.
    We have reviewed Sikorsky Alert Service Bulletin No. 92-64-002, 
dated August 3, 2007 (ASB), which describes procedures for doing a one-
time borescope inspection of the shaft and bearing assembly.
    The ASB requires inspecting the shaft and bearing assembly within 
50 hours time-in-service (TIS). This AD requires the inspection within 
20 hours TIS based on the ease of the inspection, the availability of 
borescopes, the flight hours per day for the high time helicopters 
(about 8 hours), and the potential for a helicopter to ditch while 
servicing the oil rig industry. Also, this AD requires this inspection 
between 10 and 15 hours TIS following any installation of a shaft and 
bearing assembly.
    The inspections required by this AD are interim actions; the 
manufacturer continues to investigate failure of the shaft and bearing 
assembly and we may either develop follow-on actions or a terminating 
action for the requirements of this AD.
    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 failure of a shaft and bearing assembly, loss of tail rotor 
pitch and yaw control, and subsequent loss of control of a helicopter. 
This AD requires, within 20 hours TIS, inspecting each affected shaft 
and bearing assembly at the tail rotor side and on the servo side 
through the oil filler cap. This AD also requires borescope inspecting 
each shaft and bearing assembly that is installed as a replacement. 
This inspection must be done between 10 and 15 hours TIS after 
installation. Replacing any unairworthy shaft and bearing assembly is 
required before further flight.
    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. Therefore, 
borescope inspecting the affected shaft and bearing assembly within 20 
hours TIS and before further flight following any installation of an 
affected shaft and bearing assembly are required, 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 34 helicopters, and the 
borescope inspection of the shaft and bearing assembly will take about 
2 work hours to do at an average labor rate of $80 per work hour. 
Required parts will cost about $30,864 per helicopter. Based on these 
figures, we estimate the total cost impact of the AD on U.S. operators 
to be $1,054,816.

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-2007-28971; 
Directorate Identifier 2007-SW-32-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.

[[Page 46555]]

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:

2007-17-05 Sikorsky Aircraft Corporation: Amendment 39-15163. Docket 
No. FAA-2007-28971; Directorate Identifier 2007-SW-32-AD.

Applicability

    Model S-92A helicopter, with a tail rotor pitch change shaft and 
bearing assembly (shaft and bearing assembly) part number 92358-
06303-041, installed, certificated in any category.

Compliance

    Required as indicated, unless accomplished previously.
    To prevent failure of a shaft and bearing assembly, loss of tail 
rotor pitch and yaw control, and subsequent loss of control of a 
helicopter, do the following:
    (a) Within 20 hours time-in-service (TIS), borescope inspect as 
follows:
    (1) Inspect each affected shaft and bearing assembly at tail 
rotor side by following the Accomplishment Instructions, paragraphs 
3.A.(1) through (7) and Figure 4 of Sikorsky Aircraft Corporation 
Alert Service Bulletin No. 92-64-002, dated August 3, 2007 (ASB). If 
the shaft bearing fails the inspection, replace the shaft and 
bearing assembly before further flight.
    (2) Inspect each shaft and bearing assembly on the servo side 
through the oil filler cap by following the Accomplishment 
Instructions, paragraphs B.(1) through (9) and Figures 2 and 3, of 
the ASB. If the shaft bearing fails the inspection, replace the 
shaft and bearing assembly before further flight.

    Note: Maintenance Manual SA S92A-ANM-000 pertains to the subject 
of this AD.

    (b) Between 10 and 15 hours TIS after installing a shaft and 
bearing assembly, borescope inspect it by following paragraph (a) of 
this AD.
    (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) The inspections of the shaft and bearing assembly shall be 
done by following Sikorsky Alert Service Bulletin No. 92-64-002, 
dated August 3, 2007. 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, Connecticut, phone (203) 383-
4866, e-mail address tsslibrary@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 August 21, 2007.

    Issued in Fort Worth, Texas, on August 9, 2007.
Mark R. Schilling,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
 [FR Doc. E7-15980 Filed 8-20-07; 8:45 am]

BILLING CODE 4910-13-P
