AD 2012-22-13
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-76C | Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters |
Unsafe Condition
Unintended movement of the engine control levers due to an external force to the windshield or canopy.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Within 6 months, replace the throttle stop and trigger assembly on each engine control lever and perform a throttle position check as specified in Sikorsky Alert Service Bulletin No. 76-76-6A Revision A.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 6 months of the effective date (December 20, 2012).
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Sikorsky Aircraft Corporation Model S-76C helicopters, serial numbers 760506 and 760607 through 760812.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
We are adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation (Sikorsky) Model S-76C helicopters. This AD requires installing an improved throttle stop and a wider trigger on the engine control levers (ECL). This AD was prompted by a bird-strike to the windshield that resulted in unintended movement of the engine control levers from the forward position and towards the flight-idle position, which reduced power on both engines. These actions are intended to prevent unintended movement of the ECLs, resulting in main rotor speed decay and subsequent loss of control of the aircraft.
Document Text
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[Federal Register Volume 77, Number 221 (Thursday, November 15, 2012)]
[Rules and Regulations]
[Pages 68057-68058]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2012-27049]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2012-0340; Directorate Identifier 2011-SW-073-AD;
Amendment 39-17250; AD 2012-22-13]
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 certain
Sikorsky Aircraft Corporation (Sikorsky) Model S-76C helicopters. This
AD requires installing an improved throttle stop and a wider trigger on
the engine control levers (ECL). This AD was prompted by a bird-strike
to the windshield that resulted in unintended movement of the engine
control levers from the forward position and towards the flight-idle
position, which reduced power on both engines. These actions are
intended to prevent unintended movement of the ECLs, resulting in main
rotor speed decay and subsequent loss of control of the aircraft.
DATES: This AD is effective December 20, 2012.
The Director of the Federal Register approved the incorporation by
reference of a certain document listed in this AD as of December 20,
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, telephone
(203) 383-4866, email address <a href="/cdn-cgi/l/email-protection#106463637c7972627162695063797b7f62637b693e737f7d"><span class="__cf_email__" data-cfemail="b4c0c7c7d8ddd6c6d5c6cdf4c7dddfdbc6c7dfcd9ad7dbd9">[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: Kirk Gustafson, Aerospace Engineer,
FAA, Boston Aircraft Certification Office, Engine and Propeller
Directorate, 12 New England Executive Park, Burlington, MA 01803;
telephone (781) 238-7190; email <a href="/cdn-cgi/l/email-protection#33585a41581d544640475255405c5d735552521d545c45"><span class="__cf_email__" data-cfemail="761d1f041d581103050217100519183610171758111900">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
On March 29, 2012, at 77 FR 18969, 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-76C
helicopters with serial numbers 760506 and 760607 through 760812. That
NPRM proposed to require within 6 months after the effective date of
the AD, installing an improved throttle stop and a wider trigger on
each ECL as specified in Sikorsky Alert Service Bulletin (ASB) No. 76-
76-6A, Revision A, dated May 18, 2011.
The proposed requirements were intended to prevent unintended in-
flight movement of the ECLs from the normal ``FLY'' position towards
the ``IDLE'' position, which significantly reduces engine power,
resulting in an unrecoverable loss of main rotor speed and subsequent
loss of control of the helicopter.
Comments
Two commenters, one anonymous and one from the National
Transportation Safety Board, commented that they support the NPRM (77
FR 18969, March 29, 2012).
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.
Related Service Information
We reviewed ASB 76-76-6A, which describes procedures for partially
disassembling the engine control quadrant assembly, removing the
existing throttle stop, and installing a new airworthy throttle stop.
The ASB also describes procedures to remove the existing trigger
assembly from each ECL and install a new airworthy wide trigger
assembly.
Costs of Compliance
We estimate that this AD will affect 52 helicopters of U.S.
Registry. We estimate that operators may incur the following costs in
order to comply with this AD. To replace the engine control lever stop
and trigger assemblies will require 2 work-hours at an average labor
cost of $85 per hour. Required parts will cost about $939. Based upon
these costs, we estimate a total cost of $1,109 per helicopter and a
total cost of $57,668 for the entire U.S. operator fleet.
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;
[[Page 68058]]
(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):
2012-22-13 Sikorsky Aircraft Corporation: Amendment 39-17250; Docket
No. FAA-2012-0340; Directorate Identifier 2011-SW-073-AD.
(a) Applicability
This AD applies to Sikorsky Aircraft Corporation (Sikorsky)
Model S-76C helicopters, serial numbers 760506 and 760607 through
760812, certificated in any category.
(b) Unsafe Condition
This AD defines the unsafe condition as unintended movement of
the engine control levers due to an external force to the windshield
or canopy. This condition could result in significantly reduced
engine power, unrecoverable loss of main rotor speed, and subsequent
loss of control of the helicopter.
(c) Effective Date
This AD becomes effective December 20, 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 Action
Within 6 months, replace the throttle stop and trigger assembly
on each engine control lever and perform a throttle position check
as specified in the Accomplishment Instructions, Sections 3.A and
3.B, of Sikorsky Alert Service Bulletin No. 76-76-6A Revision A,
dated May 18, 2011.
(f) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Boston Aircraft Certification Office, FAA, may
approve AMOCs for this AD. Send your proposal to: Kirk Gustafson,
Aerospace Engineer, FAA, Boston Aircraft Certification Office,
Engine and Propeller Directorate, 12 New England Executive Park,
Burlington, MA 01803; telephone (781) 238-7190; email
<a href="/cdn-cgi/l/email-protection#8ce7e5fee7a2ebf9fff8edeaffe3e2cceaededa2ebe3fa"><span class="__cf_email__" data-cfemail="402b29322b6e273533342126332f2e002621216e272f36">[email protected]</span></a>.
(2) For operations conducted under a 14 CFR part 119 operating
certificate or under 14 CFR 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: 7600: Engine
Controls.
(h) Material Incorporated by Reference
(1) The Director of the Federal Register approved the
incorporation by reference (IBR) of the service information listed
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) You must use this service information as applicable to do
the actions required by this AD, unless the AD specifies otherwise.
(i) Sikorsky Alert Service Bulletin No. 76-76-6A Revision A,
dated May 18, 2011.
(ii) Reserved.
(3) For Sikorsky service information identified in this AD,
contact Sikorsky Aircraft Corporation, Attn: Manager, Commercial
Technical Support, mailstop s581a, 6900 Main Street, Stratford, CT,
telephone (203) 383-4866, email address <a href="/cdn-cgi/l/email-protection#b2c6c1c1dedbd0c0d3c0cbf2c1dbd9ddc0c1d9cb9cd1dddf"><span class="__cf_email__" data-cfemail="d6a2a5a5babfb4a4b7a4af96a5bfbdb9a4a5bdaff8b5b9bb">[email protected]</span></a>, or
at <a href="http://www.sikorsky.com">http://www.sikorsky.com</a>.
(4) You may view this service information at the FAA, Office of
the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room
663, Fort Worth, Texas 76137.
(5) You may also view this service information 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/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued in Fort Worth, Texas, on October 30, 2012.
Kim Smith,
Directorate Manager, Rotorcraft Directorate, Aircraft Certification
Service.
[FR Doc. 2012-27049 Filed 11-14-12; 8:45 am]
BILLING CODE 4910-13-P
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