AD 2014-08849
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky | Various | Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters |
Unsafe Condition
A crack on the MRH pilot bifilar assembly lug, which could result in failure of a bifilar lug, damage to the main rotor system, and subsequent loss of control of the helicopter.
Required Actions
Inspect the lower bifilar arm assembly for a crack in the lug attachment area, and if there is a crack, replace the bifilar arm assembly with an airworthy bifilar arm assembly. If no crack is found at the initial inspection, perform a one-time torque test. Within 600 hours TIS, replace the MRH pilot, P/N 76103-08003-101, with an MRH pilot, P/N 76103-08003-102. For MRH pilots with less than 900 hours TIS, prior to accumulating 1,500 hours TIS, replace the MRH pilot, P/N 76103-08003-101, with a MRH pilot, P/N 76103-08003-102. After the effective date of this AD, do not install an MRH pilot, P/N 76103-08003-101, on any helicopter.
Compliance Time
Within 50 hours TIS, and thereafter at intervals not to exceed 50 hours TIS, inspect the lower bifilar arm assembly for a crack in the lug attachment area. Within 600 hours TIS, replace the MRH pilot, P/N 76103-08003-101, with an MRH pilot, P/N 76103-08003-102. For MRH pilots with less than 900 hours TIS, prior to accumulating 1,500 hours TIS, replace the MRH pilot, P/N 76103-08003-101, with a MRH pilot, P/N 76103-08003-102.
Affected Aircraft
Model S-76A, B, and C helicopters with a main rotor hub (MRH) pilot, part number (P/N) 76103-08003-101, installed, certificated in any category.
Federal Register Abstract
We are superseding Airworthiness Directive (AD) 2005-22-01 for Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, B, and C helicopters. AD 5002-22-01 required inspecting the main rotor lower bifilar arm assembly (bifilar arm assembly) for a crack, and if there is a crack, replacing the bifilar arm assembly. AD 2005-22-01 also required a one-time test for the correct torque on the lug nuts, and if necessary, conducting torque stabilization tests. This new AD retains the requirements of AD 2005-22-01 and also requires replacing the main rotor hub (MRH) pilot with a different part-numbered MRH pilot, which is terminating action for the requirements of the AD. This AD was prompted by the development of a terminating procedure for the inspections required by AD 2005-22-01. We are issuing this AD to prevent failure of a bifilar lug, damage to the main rotor system, and subsequent loss of control of the helicopter.
Document Text
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[Federal Register Volume 79, Number 81 (Monday, April 28, 2014)]
[Rules and Regulations]
[Pages 23260-23262]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2014-08849]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2013-0637; Directorate Identifier 2013-SW-030-AD;
Amendment 39-17830; AD 2014-08-06]
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 superseding Airworthiness Directive (AD) 2005-22-01 for
Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, B, and C
helicopters. AD 5002-22-01 required inspecting the main rotor lower
bifilar arm assembly (bifilar arm assembly) for a crack, and if there
is a crack, replacing the bifilar arm assembly. AD 2005-22-01 also
required a one-time test for the correct torque on the lug nuts, and if
necessary, conducting torque stabilization tests. This new AD retains
the requirements of AD 2005-22-01 and also requires replacing the main
rotor hub (MRH) pilot with a different part-numbered MRH pilot, which
is terminating action for the requirements of the AD. This AD was
prompted by the development of a terminating procedure for the
inspections required by AD 2005-22-01. We are issuing this AD to
prevent failure of a bifilar lug, damage to the main rotor system, and
subsequent loss of control of the helicopter.
DATES: This AD is effective June 2, 2014.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of November 10,
2005 (70 FR 61721, October 26, 2005).
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 <a href="/cdn-cgi/l/email-protection#334740405f5a514152414a73405a585c4140584a1d505c5e"><span class="__cf_email__" data-cfemail="84f0f7f7e8ede6f6e5f6fdc4f7edefebf6f7effdaae7ebe9">[email protected]</span></a>; or at <a href="http://www.sikorsky.com">http://www.sikorsky.com</a>. You may review 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 Management Facility
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 address for the Docket Office (phone: 800-
647-5527) is Document Management Facility, U.S. Department of
Transportation, Docket Operations, 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
[[Page 23261]]
Office, Engine & Propeller Directorate, 12 New England Executive Park,
Burlington, Massachusetts 01803; telephone (781) 238-7763; email
<a href="/cdn-cgi/l/email-protection#a3cdcac0cbcccfc2d08dc5c2d6d0d7e3c5c2c28dc4ccd5"><span class="__cf_email__" data-cfemail="147a7d777c7b7875673a7275616760547275753a737b62">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to supersede AD 2005-22-01, Amendment 39-14345 (70 FR 61721,
October 26, 2005) (AD 2005-22-01). AD 2005-22-01 applied to Sikorsky
Model S-76A, B, and C helicopters with a certain MRH pilot installed.
The NPRM published in the Federal Register on July 23, 2013 (78 FR
44048). AD 2005-22-01 required repetitively inspecting the bifilar arm
assembly for a crack, and replacing the bifilar arm assembly if it has
a crack. If there is not a crack, AD 2005-22-01 required a one-time
test for the correct torque on the lug nuts, and if necessary,
conducting torque stabilization.
After we issued AD 2005-22-01, Sikorsky produced a newly-redesigned
pilot with a larger flange diameter that provides greater support for
the bifilar assembly and reduces stress on the bifilar assembly
attachment lugs. The NPRM proposed to retain the repetitive inspection
requirements of AD 2005-22-01, but also proposed to require replacing
the MRH pilot, part number (P/N) 76103-08003-101, with newly-redesigned
MRH pilot, P/N 76103-08003-102, as terminating action.
Related Service Information
Sikorsky issued S-76 Alert Service Bulletin (ASB) 76-65-62, dated
December 14, 2004, which describes procedures for inspecting the lower
bifilar assembly for a crack. Sikorsky has also issued ASB 76-65-65,
Basic Issue, dated March 22, 2012, which specifies measuring the MRH
diameter and, if the diameter is small, replacing the MRH pilot with a
newly-redesigned MRH pilot with a larger flange diameter.
Comments
We gave the public the opportunity to participate in developing
this AD. We received no comments on the NPRM (78 FR 44048, July 23,
2013) or on the determination of the cost to the public.
Costs of Compliance
We estimate that this AD affects 181 helicopters of U.S. Registry.
We estimate that operators may incur the following costs in order
to comply with this AD:
<bullet> Inspecting the bifilar arm assembly requires about 4 work-
hours, at an average labor rate of $85 per hour, for a cost per
helicopter of $340 and a total cost to U.S. operators of $61,540.
<bullet> Replacing a cracked bifilar arm assembly requires about 4
work-hours, at an average labor rate of $85 per hour, and required
parts cost about $19,727, for a cost per helicopter of $20,067.
<bullet> Replacing the MRH pilot, P/N 76103-08003-101, with an MRH
pilot, P/N 76103-08003-102, requires about 0.7 work-hour, at an average
labor rate of $85 per hour, and required parts cost about $1,043, for a
cost per helicopter of $1,103 and a total cost to U.S. operators of
$199,643.
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
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 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, 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.
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 removing Airworthiness Directive (AD)
2005-22-01, Amendment 39-14345 (70 FR 61721, October 26, 2005), and
adding the following new AD:
2014-08-06 Sikorsky Aircraft Corporation: Amendment 39-17830; Docket
No. FAA-2013-0637; Directorate Identifier 2013-SW-030-AD.
(a) Applicability
This AD applies to Model S-76A, B, and C helicopters with a main
rotor hub (MRH) pilot, part number (P/N) 76103-08003-101, installed,
certificated in any category.
(b) Unsafe Condition
This AD defines the unsafe condition as a crack on the MRH pilot
bifilar assembly lug, which could result in failure of a bifilar
lug, damage to the main rotor system, and subsequent loss of control
of the helicopter.
(c) Affected ADs
This AD supersedes AD 2005-22-01, Amendment 39-14345 (70 FR
61721, October 26, 2005).
(d) Effective Date
This AD becomes effective June 2, 2014.
(e) 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.
(f) Required Actions
(1) For MRH pilots with 1,500 or more hours time-in-service
(TIS), within 50 hours TIS, and thereafter at intervals not to
exceed 50 hours TIS, inspect the lower bifilar arm assembly for a
crack in the lug attachment area. Conduct the inspection of the
lower bifilar arm assembly by following the Accomplishment
Instructions, paragraphs 3.A.(1) through 3.A.(6), of Sikorsky Alert
Service Bulletin No. 76-65-62, dated December 14, 2004 (ASB 76-65-
62).
(i) If there is a crack on any bifilar assembly arm lug, before
further flight, replace the bifilar arm assembly with an airworthy
bifilar arm assembly.
(ii) If no crack is found at the initial inspection, perform a
one-time torque test.
[[Page 23262]]
Perform the torque test and the additional torque procedures as
stated in the Accomplishment Instructions, paragraphs 3.B.(1)
through 3.B.(3), of ASB 76-65-62. The torque test is not required at
the recurring inspection intervals of the lower bifilar arm
assembly.
(iii) Within 600 hours TIS, replace the MRH pilot, P/N 76103-
08003-101, with an MRH pilot, P/N 76103-08003-102.
(2) For MRH pilots with less than 900 hours TIS, prior to
accumulating 1,500 hours TIS, replace the MRH pilot, P/N 76103-
08003-101, with a MRH pilot, P/N 76103-08003-102.
(3) After the effective date of this AD, do not install an MRH
pilot, P/N 76103-08003-101, on any helicopter.
(g) Special Flight Permit
Special flight permits will not be issued.
(h) 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, Massachusetts 01803; telephone (781) 238-7763; email
<a href="/cdn-cgi/l/email-protection#1a7473797275767b69347c7b6f696e5a7c7b7b347d756c"><span class="__cf_email__" data-cfemail="2e40474d4641424f5d00484f5b5d5a6e484f4f00494158">[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.
(i) Additional Information
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#126661617e7b706073606b52617b797d6061796b3c717d7f"><span class="__cf_email__" data-cfemail="7c080f0f10151e0e1d0e053c0f1517130e0f1705521f1311">[email protected]</span></a>; or at <a href="http://www.sikorsky.com">http://www.sikorsky.com</a>. You may review the service information at the FAA,
Office of the Regional Counsel, Southwest Region, 2601 Meacham
Blvd., Room 663, Fort Worth, Texas 76137.
(j) Subject
Joint Aircraft Service Component (JASC) Code: 6220: Main Rotor
Head.
(k) 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.
(3) The following service information was approved for IBR on
November 10, 2005 (70 FR 61721, October 26, 2005).
(i) Sikorsky Aircraft Corporation Alert Service Bulletin No. 76-
65-62, dated December 14, 2004.
(ii) Reserved.
(4) For the 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#ccb8bfbfa0a5aebeadbeb58cbfa5a7a3bebfa7b5e2afa3a1"><span class="__cf_email__" data-cfemail="532720203f3a312132212a13203a383c2120382a7d303c3e">[email protected]</span></a>; or at
<a href="http://www.sikorsky.com">http://www.sikorsky.com</a>.
(5) You may view this service information at FAA, Office of the
Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663,
Fort Worth, Texas 76137. For information on the availability of this
material at the FAA, call (817) 222-5110.
(6) You may view this service information that is incorporated
by reference 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 April 11, 2014.
Kim Smith,
Directorate Manager, Rotorcraft Directorate, Aircraft Certification
Service.
[FR Doc. 2014-08849 Filed 4-25-14; 8:45 am]
BILLING CODE 4910-13-P
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