AD 2006-11-14

final rule

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

AD Number
2006-11-14
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2006-24875
FR Citation
71 FR 30798

Applicability

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

Unsafe Condition

Failure of the main transmission mounting bolt (part number SS5211-10-47) due to wear or corrosion, which could result in loss of support of the main transmission and subsequent loss of control of the helicopter.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Inspect each of the 8 main transmission mounting bolts for wear or corrosion within 100 hours time-in-service (TIS), unless the inspection was completed within the last 500 hours TIS. Replace any bolt found with wear or corrosion, along with the bolt barrel nut and cage, before further flight.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 100 hours time-in-service (TIS), unless the inspection was completed within the last 500 hours TIS.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Sikorsky Aircraft Corporation Model S-92A helicopters with main transmission mounting bolt (part number SS5211-10-47) installed, certificated in any category.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment adopts a new airworthiness directive (AD) for the specified Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This action requires inspecting each main transmission assembly mounting bolt (bolt) for wear or corrosion, and if wear or corrosion is found, replacing the bolt, bolt barrel nut, and cage. This amendment is prompted by a report of a failure of a bolt that was discovered during a routine maintenance inspection. The actions specified in this AD are intended to prevent failure of a bolt, which could result in loss of support of the main transmission and subsequent loss of control of the helicopter.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 71, Number 104 (Wednesday, May 31, 2006)]
[Rules and Regulations]
[Pages 30798-30800]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 06-4911]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-24875; Directorate Identifier 2006-SW-03-AD; 
Amendment 39-14618; AD 2006-11-14]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD) for 
the specified Sikorsky Aircraft Corporation (Sikorsky) Model S-92A 
helicopters. This action requires inspecting each main transmission 
assembly mounting bolt (bolt) for wear or corrosion, and if wear or 
corrosion is found, replacing the bolt, bolt barrel nut, and cage. This 
amendment is prompted by a report of a failure of a bolt that was 
discovered during a routine maintenance inspection. The actions 
specified in this AD are intended to prevent failure of a bolt, which 
could result in loss of support of the main transmission and subsequent 
loss of control of the helicopter.

DATES: Effective June 15, 2006.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 15, 2006.
    Comments for inclusion in the Rules Docket must be received on or 
before July 31, 2006.

ADDRESSES: Use one of the following addresses to submit comments on 
this AD:
    <bullet> DOT Docket Web site: Go to <a href="http://dms.dot.gov">http://dms.dot.gov</a> and follow 
the instructions for sending your comments electronically;
    <bullet> Government-wide rulemaking Web site: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a> and follow the instructions for sending your 
comments electronically;
    <bullet> Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590;
    <bullet> Fax: (202) 493-2251; or
    <bullet> 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.
    You may get the service information identified in this AD from 
Sikorsky

[[Page 30799]]

Aircraft Corporation, Attn: Manager, Commercial Tech Support, 6900 Main 
Street, Stratford, Connecticut 06614, phone (203) 386-3001, fax (203) 
386-5983.

Examining the Docket

    You may examine the docket that contains the AD, any comments, and 
other information on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a>, 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 an AD for Sikorsky 
Model S-92A helicopters with bolts, part number SS5211-10-47, 
installed. This action requires opening the No. 1 and No. 2 engine work 
platforms to gain access to the bolts and inspecting each of the 8 
bolts for wear or corrosion. The inspections for wear or corrosion are 
required within 100 hours time-in-service (TIS), unless accomplished 
within the last 500 hours TIS. This action also requires, before 
further flight, replacing any bolt on which wear or corrosion is found, 
together with the bolt barrel nut and cage. This amendment is prompted 
by a report of a bolt failure, which was discovered during a routine 
1,250-hours TIS maintenance inspection. Subsequent investigation and 
analysis of the failed bolt revealed damage from wear and corrosion. 
The actions specified in this AD are intended to prevent failure of a 
bolt, which could result in loss of support of the main transmission 
and subsequent loss of control of the helicopter.
    We have reviewed Sikorsky Alert Service Bulletin (ASB) No. 92-63-
003, dated February 1, 2006, which describes inspecting the 8 bolts to 
verify that each bolt has the correct torque, as well as inspecting for 
wear or corrosion on the bolt, and replacing any bolt on which wear or 
corrosion is discovered, together with the bolt barrel nut and cage. 
The ASB also describes reporting the condition of any damaged bolt and 
returning any removed hardware to Sikorsky. This AD does not require 
verifying that each bolt has the correct torque, reporting the bolt 
torque or bolt damage information, nor returning the hardware to 
Sikorsky. Sikorsky plans to make available a redesigned bolt that 
should eliminate the fretting that leads to corrosion and subsequent 
failure of the bolt. In light of that information, we anticipate that 
we will later issue further AD action to require repetitive inspections 
at intervals of 500 hours TIS until that bolt is made available by 
Sikorsky and is installed on helicopters.
    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 bolt, which could result in loss of support of 
the main transmission and subsequent loss of control of the helicopter. 
Accomplish the actions by following the specified portions of the ASB 
described previously. The short compliance time is required because the 
previously described critical unsafe condition can adversely affect the 
structural integrity and controllability of the helicopter. Since the 
fleet has helicopters accruing 8 to 10 hours TIS per day, those 
helicopters could accrue 100 hours TIS in approximately 2 weeks of 
operation. Therefore, inspecting each bolt for wear or corrosion is 
required within 100 hours TIS and replacing any bolt on which wear or 
corrosion is found, as well as replacing the bolt barrel nut and cage, 
are 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 8 helicopters, and the 
inspections for wear or corrosion will take approximately 3.5 work 
hours to accomplish at an average labor rate of $80 per work hour. 
Required parts will cost approximately $197 for each bolt, $28 for each 
bolt barrel nut, and $4 for each cage. Based on these figures, we 
estimate the total cost impact of the AD on U.S. operators to be $4,072 
per helicopter, assuming that replacing 8 bolts, 8 bolt barrel nuts, 
and 8 cages is necessary.

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-2006-24875; 
Directorate Identifier 2006-SW-03-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 <a href="http://dms.dot.gov">http://dms.dot.gov</a>, 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 <a href="http://dms.dot.gov">http://dms.dot.gov</a>.

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

[[Page 30800]]

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:

2006-11-14 Sikorsky Aircraft Corporation: Amendment 39-14618. Docket 
No. FAA-2006-24875; Directorate Identifier 2006-SW-03-AD.

Applicability

    Model S-92A helicopters, with main transmission mounting bolt 
(bolt), part number (P/N) SS5211-10-47, installed, certificated in 
any category.

Compliance

    Required as indicated.
    To prevent failure of a bolt, which could result in loss of 
support of the main transmission and subsequent loss of control of 
the helicopter, accomplish the following:
    (a) Within 100 hours time-in-service (TIS), unless accomplished 
within the last 500 hours TIS, open the No. 1 and No. 2 engine work 
platforms to gain access to the 8 bolts. Remove each bolt, one at a 
time, and visually inspect the bolt shank and threads for wear or 
corrosion in accordance with paragraphs 3.A.(6)(a) of the 
Accomplishment Instructions in Sikorsky Aircraft Corporation Alert 
Service Bulletin No. 92-63-003, dated February 1, 2006 (ASB). 
Reporting the condition of the mounting bolt, tagging the mounting 
bolt with location, and sending the removed mounting bolt and barrel 
nut to Sikorsky Aircraft Corporation are not required to satisfy the 
requirements of this AD.
    (b) Before further flight, replace any bolt on which wear or 
corrosion is found, as well as the bolt barrel nut and cage, with an 
airworthy bolt, P/N SS5211-10-47, barrel nut, P/N RMLH2577-108, and 
cage, P/N NAS578-10B.
    (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, Engine 
and Propeller Directorate, 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 shall be done in accordance with the 
specified paragraphs of Sikorsky Aircraft Corporation Alert Service 
Bulletin No. 92-63-003, dated February 1, 2006. 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 Tech Support, 6900 Main Street, Stratford, Connecticut 
06614, phone (203) 386-3001, fax (203) 386-5983. Copies may be 
inspected 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: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
    (e) This amendment becomes effective on June 15, 2006.

    Issued in Fort Worth, Texas, on May 18, 2006.
Judy I. Carl,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 06-4911 Filed 5-30-06; 8:45 am]
BILLING CODE 4910-13-P

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