AD 2006-11-14
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| 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.
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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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