AD 2015-04-05
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-76A | Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-76B | Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-76C | Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-76D | Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Helicopters |
Unsafe Condition
Looseness or fracture of the tail rotor drive shaft (TDS) flange-to-shaft attachment hardware, which could lead to failure at the flange-to-shaft attachment and loss of tail rotor drive, potentially resulting in loss of control of the helicopter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the TDS flange-to-shaft attachment hardware at four locations for correct installation and torque. If discrepancies are found, apply an index mark to the flange and shaft, inspect for cracks, fractures, wear, and measurements, and replace any part not meeting criteria. Reinstall the flange with proper alignment and torque the nuts.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 30 days
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Sikorsky Model S-76A, B, C, and D helicopters.
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 Model S-76A, B, C, and D helicopters. This AD requires inspecting the tail rotor drive shaft (TDS) flange-to-shaft attachment hardware for correct assembly and correct torque of the fasteners. If there is a discrepancy, this AD requires, before further flight, applying an index mark to the flange and TDS, inspecting the flange and shaft for a crack, fracture, wear, and certain measurements, and replacing any part that does not meet the approved criteria before further flight. This AD is prompted by a partial loss of tail rotor drive resulting in a forced landing. The actions specified by this AD are intended to prevent failure at the flange-to-shaft attachment, loss of a tail rotor drive, and subsequent loss of control of the helicopter.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 80, Number 37 (Wednesday, February 25, 2015)]
[Rules and Regulations]
[Pages 9985-9987]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2015-03703]
========================================================================
Rules and Regulations
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains regulatory documents
having general applicability and legal effect, most of which are keyed
to and codified in the Code of Federal Regulations, which is published
under 50 titles pursuant to 44 U.S.C. 1510.
The Code of Federal Regulations is sold by the Superintendent of Documents.
Prices of new books are listed in the first FEDERAL REGISTER issue of each
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========================================================================
Federal Register / Vol. 80, No. 37 / Wednesday, February 25, 2015 /
Rules and Regulations
[[Page 9985]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2015-0397; Directorate Identifier 2014-SW-048-AD;
Amendment 39-18107; AD 2015-04-05]
RIN 2120-AA64
Airworthiness Directives; Sikorsky Aircraft Corporation
(Sikorsky) Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
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SUMMARY: We are adopting a new airworthiness directive (AD) for certain
Sikorsky Model S-76A, B, C, and D helicopters. This AD requires
inspecting the tail rotor drive shaft (TDS) flange-to-shaft attachment
hardware for correct assembly and correct torque of the fasteners. If
there is a discrepancy, this AD requires, before further flight,
applying an index mark to the flange and TDS, inspecting the flange and
shaft for a crack, fracture, wear, and certain measurements, and
replacing any part that does not meet the approved criteria before
further flight. This AD is prompted by a partial loss of tail rotor
drive resulting in a forced landing. The actions specified by this AD
are intended to prevent failure at the flange-to-shaft attachment, loss
of a tail rotor drive, and subsequent loss of control of the
helicopter.
DATES: This AD becomes effective March 12, 2015.
The Director of the Federal Register approved the incorporation by
reference of a certain document as of March 12, 2015.
We must receive comments on this AD by April 27, 2015.
ADDRESSES: You may send comments by any of the following methods:
<bullet> Federal eRulemaking Docket: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a>. Follow the online instructions for sending your
comments electronically.
<bullet> Fax: 202-493-2251.
<bullet> Mail: Send comments to the U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590-0001.
<bullet> Hand Delivery: Deliver to the ``Mail'' address between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
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 (telephone 800-647-5527) is in the ADDRESSES section. Comments
will be available in the AD docket shortly after receipt.
For service information identified in this AD, contact Sikorsky
Aircraft Corporation, Customer Service Engineering, 124 Quarry Road,
Trumbull, CT 06611; telephone 1-800-Winged-S or 203-416-4299; email
<a href="/cdn-cgi/l/email-protection#0172686a6e73726a787662724172686a6e73726a782f626e6c"><span class="__cf_email__" data-cfemail="8bf8e2e0e4f9f8e0f2fce8f8cbf8e2e0e4f9f8e0f2a5e8e4e6">[email protected]</span></a>. You may review the referenced service
information at the FAA, Office of the Regional Counsel, Southwest
Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. It is
also available on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by
searching for and locating Docket No. FAA-2015-0397.
FOR FURTHER INFORMATION CONTACT: Michael Schwetz, Aviation Safety
Engineer, Boston Aircraft Certification Office, Engine & Propeller
Directorate, FAA, 12 New England Executive Park, Burlington,
Massachusetts 01803; telephone (781) 238-7761; email
<a href="/cdn-cgi/l/email-protection#117c78727970747d3f6272796674656b517770703f767e67"><span class="__cf_email__" data-cfemail="3b565258535a5e57154858534c5e4f417b5d5a5a155c544d">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Comments Invited
This AD is a final rule that involves requirements affecting flight
safety, and we did not provide you with notice and an opportunity to
provide your comments prior to it becoming effective. However, we
invite you to participate in this rulemaking by submitting written
comments, data, or views. We also invite comments relating to the
economic, environmental, energy, or federalism impacts that resulted
from adopting this AD. The most helpful comments reference a specific
portion of the AD, explain the reason for any recommended change, and
include supporting data. To ensure the docket does not contain
duplicate comments, commenters should send only one copy of written
comments, or if comments are filed electronically, commenters should
submit them only one time. We will file in the docket all comments that
we receive, as well as a report summarizing each substantive public
contact with FAA personnel concerning this rulemaking during the
comment period. We will consider all the comments we receive and may
conduct additional rulemaking based on those comments.
Discussion
We are adopting a new AD for certain Sikorsky Model S-76A, B, C,
and D helicopters. This AD requires inspecting the TDS flange-to-shaft
attachment hardware at four locations for correct installation and
correct torque of the fasteners. If there is movement, misalignment of
the torque stripe, a misassembled part, or torque of less than 105
inch-pounds on any nut, this AD requires applying an index mark to the
flange and shaft to make sure the flange is reinstalled in the same
position to maintain shaft balance, and, before further flight,
inspecting the flange and shaft for a crack, fracture, wear on the
mounting hole, and diameter measurements, and replacing the TDS if the
flange or stub does not meet the inspection criteria. This AD is
prompted by a partial loss of tail rotor drive resulting in a forced
landing, and instances where TDS flange-to-shaft attachment hardware
was found to be loose or fractured. The actions specified by this AD
are intended to detect loose or fractured hardware and prevent failure
of the TDS at the flange-to-shaft attachment, loss of a tail rotor
drive, and
[[Page 9986]]
subsequent loss of control of the helicopter.
FAA's Determination
We are issuing this AD because we evaluated all the relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of these same type
designs.
Related Service Information Under 1 CFR Part 51
Sikorsky issued Alert Service Bulletin ASB 76-66-52, Basic Issue,
on April 1, 2014, which specifies a one-time inspection of the TDS
flange-to-shaft attachment hardware for proper installation and torque.
If there is movement, torque stripe misalignment, or misassembled
hardware, the ASB specifies removing and returning the hardware to
Sikorsky with certain forms and replacing hardware with airworthy TDS
hardware before returning the helicopter to service. The ASB also
specifies either replacing the TDS or inspecting the flange and shaft
for a crack, fracture, wear of the mounting hole, and diameter and
replacing any part that does not meet the approved criteria. The ASB
states there were instances where the TDS flange-to-shaft attachment
hardware was found loose or fractured. This service information is
reasonably available; see ADDRESSES for ways to access this service
information.
AD Requirements
This AD requires, within 30 days:
<bullet> Inspecting each TDS flange attachment hardware at all four
locations for looseness and torque stripe misalignment, inspecting each
nut to determine whether it can be rotated by hand, determining whether
the hardware is assembled correctly, and determining the torque of each
nut.
<bullet> If there is no looseness, torque stripe misalignment,
incorrect hardware assembly, and if no nut can be rotated by hand and
the torque of any nut is not less than 105 inch-pounds, no further
action is required by this AD.
<bullet> If there is looseness, torque stripe misalignment,
incorrect hardware assembly, a nut rotated by hand, or the torque of
any nut is less than 105 inch-pounds:
[cir] Applying an index mark to the flange and shaft, unbolting and
removing the flange from the shaft, visually inspecting each radius
washer for wear or fretting, and replacing any washer with wear or
fretting.
[cir] Inspecting the flange and shaft for a crack, fracture, wear
on the mounting hole, and diameter, and replacing the TDS with an
airworthy TDS if the flange and shaft fail any of the inspection
criteria.
[cir] Aligning index marks, installing the flange on the shaft, and
coating the grip length of each bolt and the contact surfaces on each
radius washer and washer with epoxy polyamide primer.
[cir] Torquing each nut.
Differences Between This AD and the Service Information
The AD does not require returning the unairworthy parts with
certain forms to the manufacturer as does the service information.
Costs of Compliance
We estimate that this AD affects 260 helicopters of U.S. Registry.
We estimate that operators may incur the following costs in order to
comply with this AD. We estimate $85 per work-hour for labor. We
estimate 2.2 work-hours to inspect the hardware assembly and torque at
a cost of $187 per helicopter and $48,620 for the fleet. We estimate
2.2 work-hours if the hardware is replaced and $1,200 for the required
parts, for a total cost of $1,387 per helicopter.
FAA's Justification and Determination of the Effective Date
Providing an opportunity for public comments before adopting these
AD requirements would delay implementing the safety actions needed to
correct this known unsafe condition. Therefore, we find that the risk
to the flying public justifies waiving notice and comment before
adopting this rule because the required corrective actions must be done
within 30 days, a very short time period based on the average flight-
hour utilization rate of these helicopters used for commuter, air
ambulance, and offshore operations.
Since an unsafe condition exists that requires the immediate
adoption of this AD, we determined that notice and opportunity for
public comment before issuing this AD are impracticable and that good
cause exists for making this amendment effective in less than 30 days.
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 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, 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):
2015-04-05 Sikorsky Aircraft Corporation: Amendment 39-18107; Docket
No. FAA-2015-0397; Directorate Identifier 2014-SW-048-AD.
[[Page 9987]]
(a) Applicability
This AD applies to Model S-76A, S-76B, S-76C, and S-76D
helicopters, serial numbers (S/N) up to and including 761050,
certificated in any category, with a tail drive shaft (TDS) part
number (P/N) and S/N as follows:
(a) P/N 76361-04004 (all dash numbers) with an S/N up to and
including A127-01092; or
(b) P/N 76361-04604 (all dash numbers) with an S/N with a prefix
A240 or B240, or with an S/N C240-00001 through C240-00880.
(b) Unsafe Condition
This AD defines the unsafe condition as loose or fractured TDS
flange-to-shaft attachment hardware. This condition could result in
loss of a tail rotor drive and subsequent loss of control of the
helicopter.
(c) Effective Date
This AD becomes effective March 12, 2015.
(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 30 hours time-in-service:
(1) Inspect each TDS flange attachment hardware at all four
locations for looseness and torque stripe misalignment as depicted
in Figure 1 and shown in Figure 2 of Sikorsky Aircraft Corporation
Alert Service Bulletin ASB 76-66-52, Basic Issue, dated April 1,
2014 (ASB). Inspect each nut to determine whether it can be rotated
by hand. Determine whether the hardware is assembled correctly by
following the Accomplishment Instructions, paragraph B.(3)(a)
through B.(3)(b) of the ASB. Determine the torque of each nut.
(2) If there is no looseness, torque stripe misalignment,
incorrect hardware assembly, and if no nut can be rotated by hand
and the torque of any nut is not less than 105 inch-pounds, no
further action is required by this AD.
(3) If there is looseness, torque stripe misalignment, incorrect
hardware assembly, a nut rotated by hand, or the torque of any nut
is less than 105 inch-pounds, do the following:
(i) Apply an index mark to the flange and shaft to make sure the
flange is reinstalled in the same position and to maintain shaft
balance, unbolt and remove the flange from the shaft, and visually
inspect each radius washer for wear or fretting. Replace any washer
with wear or fretting.
(ii) Inspect the flange and shaft for a crack, fracture, wear on
the mounting hole, and diameter by following the Accomplishment
Instructions, paragraph 3.D.(5)(a) through 3.D.(5)(e), of the ASB.
If the flange and shaft fail any of the inspection criteria, before
further flight, replace the TDS with an airworthy TDS.
(iii) Align index marks, install the flange on the shaft, and
coat the grip length of each bolt and the contact surfaces on each
radius washer and washer with epoxy polyamide primer.
(iv) Torque each nut by following either paragraph D.(9) or
D.(10) of the Accomplishment Instructions of the ASB.
(f) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Boston Aircraft Certification Office, FAA, may
approve AMOCs for this AD. Send your proposal to: Michael Schwetz,
Aviation Safety Engineer, Engine & Propeller Directorate, FAA, 12
New England Executive Park, Burlington, Massachusetts 01803;
telephone (781) 238-7761; email <a href="/cdn-cgi/l/email-protection#fc91959f949d9990d28f9f948b998886bc9a9d9dd29b938a"><span class="__cf_email__" data-cfemail="90fdf9f3f8f1f5fcbee3f3f8e7f5e4ead0f6f1f1bef7ffe6">[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: 6510 Tail Rotor
Drive Shaft.
(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 Aircraft Corporation Alert Service Bulletin ASB 76-
66-52, Basic issue, dated April 1, 2014.
(ii) Reserved.
(3) For Sikorsky Aircraft Corporation service information
identified in this AD, contact Sikorsky Aircraft Corporation,
Customer Service Engineering, 124 Quarry Road, Trumbull, CT 06611;
telephone 1-800-Winged-S or 203-416-4299; email
<a href="/cdn-cgi/l/email-protection#36455f5d5944455d4f41554576455f5d5944455d4f1855595b"><span class="__cf_email__" data-cfemail="3043595b5f42435b494753437043595b5f42435b491e535f5d">[email protected]</span></a>.
(4) 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.
(5) 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 February 9, 2015.
Bruce E. Cain,
Acting Directorate Manager, Rotorcraft Directorate, Aircraft
Certification Service.
[FR Doc. 2015-03703 Filed 2-24-15; 8:45 am]
BILLING CODE 4910-13-P
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