AD 2014-08849

final rule

Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

AD Number
2014-08849
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2013-0637
FR Citation
79 FR 23260
Technical illustration of a helicopter rotor hub assembly
Problem area Rotor system

Applicability

TypeManufacturerModelDetails
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

Show stored source text (verify against official source)
[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&#160;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&#160;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&#160;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&#160;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&#160;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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