Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

[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 [www.gpo.gov]
[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]]

[email protected]; or at http://www.sikorsky.com. 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 http://www.regulations.gov; 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 [email protected].

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 
[email protected].
    (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 [email protected]; or at 
http://www.sikorsky.com.
    (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: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

    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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