AD 2012-06-24
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-92A | Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters |
Unsafe Condition
Mislocated aluminum wire mesh in the blade skin leaves portions of the graphite torque tube (spar) region unprotected from a lightning strike.
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Required Actions
Within 60 days, inspect the upper and lower airfoils of each tail rotor blade to determine if the wire mesh is mislocated. If mislocated, replace the blade with an airworthy blade before further flight.
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Compliance Time
Within 60 days
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Affected Aircraft
Sikorsky Aircraft Corporation Model S-92A helicopters with tail rotor blade assembly part numbers 92170-11000-044, -045, and -046, with a serial number with a prefix of 'A111' and a number equal to or less than '-00585', installed.
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Federal Register Abstract
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD was prompted by the discovery of tail rotor blade assemblies (blades) manufactured with mislocated aluminum wire mesh, leaving portions of the graphite torque tube (spar) region unprotected from a lightning strike. The actions are intended to detect mislocated blade wire mesh and to prevent spar delamination, loss of the blade tip cap during a lightning strike, blade imbalance, loss of a blade, and subsequent loss of control of the helicopter.
Document Text
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[Federal Register Volume 77, Number 69 (Tuesday, April 10, 2012)]
[Rules and Regulations]
[Pages 21402-21404]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2012-8052]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2011-1113; Directorate Identifier 2009-SW-53-AD;
Amendment 39-17005; AD 2012-06-24]
RIN 2120-AA64
Airworthiness Directives; Sikorsky Aircraft Corporation
Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: We are adopting a new airworthiness directive (AD) for
Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This
AD was prompted by the discovery of tail rotor blade assemblies
(blades) manufactured with mislocated aluminum wire mesh, leaving
portions of the graphite torque tube (spar) region unprotected from a
lightning strike. The actions are intended to detect mislocated blade
wire mesh and to prevent spar delamination, loss of the blade tip cap
during a lightning strike, blade imbalance, loss of a blade, and
subsequent loss of control of the helicopter.
DATES: This AD is effective May 15, 2012.
The Director of the Federal Register approved the incorporation by
reference of certain documents listed in this AD as of May 15, 2012.
ADDRESSES: For service information identified in this AD, contact
Sikorsky Aircraft Corporation, Attn: Manager, Commercial Technical
Support, mailstop s581a, 6900 Main Street, Stratford, CT 06614;
telephone (800) 562-4409; email
[[Page 21403]]
<a href="/cdn-cgi/l/email-protection#ccb8bfbfa0a5aebeadbeb58cbfa5a7a3bebfa7b5e2afa3a1"><span class="__cf_email__" data-cfemail="9de9eeeef1f4ffeffcefe4ddeef4f6f2efeef6e4b3fef2f0">[email protected]</span></a>; or at <a href="http://www.sikorsky.com">http://www.sikorsky.com</a>. You may review
a copy of the referenced service information at the FAA, Office of the
Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort
Worth, Texas 76137.
Examining the AD Docket: You may examine the AD docket on the
Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a>; or in person at the Docket
Operations Office between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays. The AD docket contains this AD, any
incorporated-by-reference service information, the economic evaluation,
any comments received, and other information. The street address for
the Docket Operations Office (phone: 800-647-5527) is U.S. Department
of Transportation, Docket Operations Office, M-30, West Building Ground
Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Nicholas Faust, Aviation Safety
Engineer, Boston Aircraft Certification Office, Engine & Propeller
Directorate, 12 New England Executive Park, Burlington, MA 01803;
telephone (781) 238-7763; email <a href="/cdn-cgi/l/email-protection#fa9493999295969b89d49c9b8f898eba9c9b9bd49d958c"><span class="__cf_email__" data-cfemail="b0ded9d3d8dfdcd1c39ed6d1c5c3c4f0d6d1d19ed7dfc6">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
On October 26, 2011, at 76 FR 66209, the Federal Register published
our Notice of proposed rulemaking (NPRM), which proposed to amend 14
CFR part 39 to include an AD that would apply to Sikorsky Model S-92A
helicopters with a tail rotor blade assembly (blade) part numbers (P/N)
92170-11000-044, -045, and -046, with a serial number with a prefix of
``A111'' and a number equal to or less than ``-00585,'' installed,
certificated in any category. That NPRM proposed to require inspecting
each blade to determine if the wire mesh is mislocated and replacing
the blade with an airworthy blade if the wire mesh is mislocated. The
proposed requirements were intended to detect mislocated blade wire
mesh and to prevent spar delamination, loss of the blade tip cap during
a lightning strike, blade imbalance, loss of a blade, and subsequent
loss of control of the helicopter.
Comments
We gave the public the opportunity to participate in developing
this AD, but we did not receive any comments on the NPRM.
Related Service Information
Sikorsky issued Special Service Instructions SSI No. 92-021A,
Revision A, dated October 21, 2009 (SSI), which specifies inspecting
the blade for mislocated blade wire mesh. Two options are identified in
the SSI. One option is to conduct an eddy current inspection and the
other option is to conduct a visual inspection after sanding to
determine if there is mislocated wire mesh.
FAA's Determination
We have reviewed the relevant information and determined that an
unsafe condition exists and is likely to exist or develop on other
products of the same type design and that air safety and the public
interest require adopting the AD requirements as proposed except for
formatting changes. These formatting changes will not increase the
economic burden on any operator nor increase the scope of the AD.
Costs of Compliance
We estimate that this AD will affect 44 helicopters of U.S.
Registry. There are 486 suspect blades worldwide and we assume 29
percent (141) of those blades may be on helicopters of U.S. registry.
We estimate that operators may incur the following costs in order
to comply with this AD. We estimate that inspecting a blade for
mislocated wire mesh will take about 4 work-hours per blade, assuming
all operators opt to do the blade sanding inspection rather than the
eddy current inspection, at an average labor rate of $85 per work-hour.
Required parts will cost about $13,000 for each blade repaired by the
manufacturer or $180,000 for each new blade. The total cost of the AD
for U.S. operators is $3,215,940, assuming 51 blades are found with
mislocated wire mesh, and assuming 36 of those blades are replaced with
blades repaired by the manufacturer and 15 blades are replaced with new
blades.
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.
Regulatory Findings
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 this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866;
(2) Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979);
(3) Will not affect intrastate aviation in Alaska to the extent
that it justifies making a regulatory distinction; and
(4) 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 and placed it in the AD docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 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. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive (AD):
2012-06-24 Sikorsky Aircraft Corporation: Amendment 39-17005; Docket
No. FAA-2011-1113; Directorate Identifier 2009-SW-53-AD.
(a) Applicability
This AD applies to Sikorsky Aircraft Corporation (Sikorsky)
Model S-92A helicopters with a tail rotor blade assembly (blade),
part number (P/N) 92170-11000-044, -045, and -046, with a serial
number with a prefix of ``A111'' and a number equal to or less than
``-00585,'' installed, certificated in any category.
[[Page 21404]]
(b) Unsafe Condition
This AD defines the unsafe condition as mislocated aluminum wire
mesh in the blade skin which leaves portions of the graphite torque
tube (spar) region unprotected from a lightning strike. This
condition could result in spar delamination, loss of the blade tip
cap during a lightning strike, blade imbalance, loss of a blade, and
subsequent loss of control of the helicopter.
(c) Effective Date
This AD becomes effective May 15, 2012.
(d) Compliance
You are responsible for performing each action required by this
AD within the specified compliance time unless it has already been
accomplished prior to that time.
(e) Required Actions
Within 60 days, inspect the upper and lower airfoils of each
tail rotor blade to determine if the wire mesh is mislocated.
(1) Inspect by using either an eddy current inspection in
accordance with paragraphs B.(1)(a) through B.(1)(o) or using the
hand-sanding method and visually inspecting in accordance with
paragraphs B.(2)(a) through B.(2)(d) of Sikorsky Special Service
Instructions SSI No. 92-021A, Revision A, dated October 21, 2009,
except you are not required to contact or report nonconforming
blades to the manufacturer. If you sand and visually inspect and
confirm the correct location of the wire mesh, touch-up and repaint
the sanded area.
(2) If there is a blade with a mislocated wire mesh, before
further flight, replace the blade with an airworthy blade.
(f) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Boston Aircraft Certification Office, FAA, may
approve AMOCs for this AD. Send your proposal to: Nicholas Faust,
Aviation Safety Engineer, Boston Aircraft Certification Office,
Engine & Propeller Directorate, 12 New England Executive Park,
Burlington, MA 01803; telephone (781) 238-7763; email
<a href="/cdn-cgi/l/email-protection#026c6b616a6d6e63712c6463777176426463632c656d74"><span class="__cf_email__" data-cfemail="fd93949e9592919c8ed39b9c888e89bd9b9c9cd39a928b">[email protected]</span></a>.
(2) For operations conducted under a Part 119 operating
certificate or under Part 91, Subpart K, we suggest that you notify
your principal inspector, or lacking a principal inspector, the
manager of the local flight standards district office or certificate
holding district office before operating any aircraft complying with
this AD through an AMOC.
(g) Subject
Joint Aircraft Service Component (JASC) Code: 6410, Tail Rotor
Blades.
(h) Material Incorporated by Reference
(1) You must use the specified portions of Sikorsky Special
Service Instructions SSI No. 92-021A, Revision A, dated October 21,
2009, to do the specified actions required by this AD. The Director
of the Federal Register approved the incorporation by reference of
this service information under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) For service information identified in this AD, contact
Sikorsky Aircraft Corporation, Attn: Manager, Commercial Technical
Support, mailstop s581a, 6900 Main Street, Stratford, CT 06614;
telephone (800) 562-4409; email <a href="/cdn-cgi/l/email-protection#b9cdcacad5d0dbcbd8cbc0f9cad0d2d6cbcad2c097dad6d4"><span class="__cf_email__" data-cfemail="285c5b5b44414a5a495a51685b4143475a5b4351064b4745">[email protected]</span></a>; or at
<a href="http://www.sikorsky.com">http://www.sikorsky.com</a>.
(3) You may review a copy of the referenced service information
at the FAA, Office of the Regional Counsel, Southwest Region, 2601
Meacham Blvd., Room 663, Fort Worth, Texas 76137 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: <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>.
Issued in Fort Worth, Texas, on March 20, 2012.
Kim Smith,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2012-8052 Filed 4-9-12; 8:45 am]
BILLING CODE 4910-13-P
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