AD 2013-20-51
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Agusta S.p.A. | A109A | Airworthiness Directives; AgustaWestland S.p.A. (Agusta) Helicopters |
| aircraft | Agusta S.p.A. | A109A II | Airworthiness Directives; AgustaWestland S.p.A. (Agusta) Helicopters |
| aircraft | Agusta S.p.A. | A109C | Airworthiness Directives; AgustaWestland S.p.A. (Agusta) Helicopters |
| aircraft | Agusta S.p.A. | A109E | Airworthiness Directives; AgustaWestland S.p.A. (Agusta) Helicopters |
| aircraft | Agusta S.p.A. | A109K2 | Airworthiness Directives; AgustaWestland S.p.A. (Agusta) Helicopters |
| aircraft | Agusta S.p.A. | A109S | Airworthiness Directives; AgustaWestland S.p.A. (Agusta) Helicopters |
| aircraft | Agusta S.p.A. | A119 | Airworthiness Directives; AgustaWestland S.p.A. (Agusta) Helicopters |
| aircraft | Agusta S.p.A. | AW109SP | Airworthiness Directives; AgustaWestland S.p.A. (Agusta) Helicopters |
| aircraft | Agusta S.p.A. | AW119 MKII | Airworthiness Directives; AgustaWestland S.p.A. (Agusta) Helicopters |
Unsafe Condition
Cracking on Thomas coupling nuts that connect the flexible disc coupling with the splined adapter on the tail rotor drive shaft, resulting from a production deficiency (hydrogen embrittlement).
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Visually inspect each Thomas coupling nut, P/N MS21042L4, along the tail rotor drive shaft line for a crack. If any nut is cracked, replace all nuts with nuts, P/N NAS1805-4, before further flight. Replace all nuts, P/N MS21042L4, with nuts, P/N NAS1805-4, within 10 hours time-in-service (TIS) or 30 days, whichever occurs first. Prohibit installing a Thomas coupling nut, P/N MS21042L4, on any tail rotor drive shaft line.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight for inspection and replacement if cracked; within 10 hours TIS or 30 days for replacement of all nuts, whichever occurs first.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
AgustaWestland S.p.A. (Agusta) Model A109A, A109A II, A109C, A109E, A109K2, A109S, AW109SP, A119, and AW119 MKII 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 Agusta Model A109A, A109A II, A109C, A109E, A109K2, A109S, AW109SP, A119, and AW119 MKII helicopters. The emergency AD was sent previously to all known U.S. owners and operators of these helicopters. This AD requires, before further flight, inspecting certain Thomas coupling nuts on the tail rotor drive shaft line for a crack and replacing all the nuts if any nut is cracked. Also this AD requires replacing all affected Thomas coupling nuts within 10 hours time-in-service (TIS) or 30 days, whichever occurs first. This AD was prompted by two incidents of cracking on the nuts that connect the flexible disc coupling (Thomas coupling) with the splined adapter on the tail rotor drive shaft. We are issuing this AD to correct the unsafe condition on these helicopters.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 78, Number 207 (Friday, October 25, 2013)]
[Rules and Regulations]
[Pages 63850-63852]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2013-24937]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2013-0881; Directorate Identifier 2013-SW-056-AD;
Amendment 39-17628; AD 2013-20-51]
RIN 2120-AA64
Airworthiness Directives; AgustaWestland S.p.A. (Agusta)
Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
-----------------------------------------------------------------------
SUMMARY: We are adopting a new airworthiness directive (AD) for Agusta
Model A109A, A109A II, A109C, A109E, A109K2, A109S, AW109SP, A119, and
AW119 MKII helicopters. The emergency AD was sent previously to all
known U.S. owners and operators of these helicopters. This AD requires,
before further flight, inspecting certain Thomas coupling nuts on the
tail rotor drive shaft line for a crack and replacing all the nuts if
any nut is cracked. Also this AD requires replacing all affected Thomas
coupling nuts within 10 hours time-in-service (TIS) or 30 days,
whichever occurs first. This AD was prompted by two incidents of
cracking on the nuts that connect the flexible disc coupling (Thomas
coupling) with the splined adapter on the tail rotor drive shaft. We
are issuing this AD to correct the unsafe condition on these
helicopters.
DATES: This AD is effective October 25, 2013 to all persons except
those persons to whom it was made immediately effective by Emergency AD
2013-20-51, issued on October 3, 2013, which contained the requirements
of this amendment.
We must receive comments on this AD by December 24, 2013.
ADDRESSES: You may send comments by any of the following methods:
<bullet> Federal eRulemaking Portal: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a>. Follow the instructions for submitting comments.
<bullet> Fax: 202-493-2251.
<bullet> Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE., Washington, DC 20590.
<bullet> Hand Delivery: Deliver to Mail address above 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, the foreign authority's AD,
the economic evaluation, any comments received, and other information.
The street address for the Docket Operations Office (phone: 800-647-
5527) is in the ADDRESSES section.
For service information identified in this AD, contact Agusta
Westland, Customer Support & Services, Via Per Tornavento 15, 21019
Somma Lombardo (VA) Italy, ATTN: Giovanni Cecchelli; telephone 39-0331-
711133; fax 39 0331 711180; or at <a href="http://www.agustawestland.com/technical-bullettins">http://www.agustawestland.com/technical-bullettins</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.
FOR FURTHER INFORMATION CONTACT: Gary Roach, Aviation Safety Engineer,
Regulations and Policy Group, Rotorcraft Directorate, FAA, 2601 Meacham
Blvd., Fort Worth, TX 76137; telephone: (817) 222-5110; email
<a href="/cdn-cgi/l/email-protection#036462717a2d612d716c62606b436562622d646c75"><span class="__cf_email__" data-cfemail="61060013184f034f130e000209210700004f060e17">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
On October 3, 2013, we issued Emergency AD 2013-20-51, which
requires, before further flight, inspecting certain Thomas coupling
nuts on the tail rotor drive shaft line for a crack and replacing all
the nuts if any nut is cracked. Also the emergency AD requires
replacing all affected Thomas coupling nuts within 10 hours TIS or 30
days, whichever occurs first. This emergency AD was sent previously to
all known U.S. owners and operators of these helicopters. This action
was prompted by two incidents of cracking on the nuts that connect the
flexible disc coupling (Thomas coupling) with the splined adapter on
the tail rotor drive shaft.
The European Aviation Safety Agency (EASA), which is the Technical
Agent for the Member States of the European Union, has issued EASA AD
No. 2013-
[[Page 63851]]
0225-E, dated September 20, 2013, to correct an unsafe condition for
certain Agusta Model A109A, A109A II, A109C, A109E, A109K2, A109S,
AW109SP, A119, and AW119 MKII helicopters. The EASA advises that during
scheduled inspection on the tail rotor drive shaft line of two in-
service Model AW109SP helicopters, one part-numbered nut that connects
the Thomas coupling with the splined adapter was cracked. The
subsequent investigation identified that the reported cracks of the
nuts are the results of a production deficiency (hydrogen
embrittlement) at the nut supplier.
Related Service Information
Agusta has issued the following service information:
<bullet> Alert Bollettino Tecnico (ABT) No. 109K-58 for all Model
A109K2 helicopters;
<bullet> ABT No. 109-136, for all Model A109A, A109A II, and A109C
helicopters;
<bullet> ABT No. 109EP-130, for Model A109E helicopters up to and
including serial number (S/N) 11832, except S/N 11796, from 11808 to
11810, and from 11812 to 11829;
<bullet> ABT No. 109L-066 for all Model A109LUH helicopters;
<bullet> ABT No. 109S-055, for all Model A109S helicopters;
<bullet> ABT No. 109SP-069, for Model AW109SP helicopters up to
including S/N 22316, except S/N 22284, 22286, 22307, and 22308; and
<bullet> ABT No. 119-061 for Model A119 and AW119 MKII helicopters
up to and including S/N 14811, except S/N 14805 and 14807.
All the ABTs are dated September 20, 2013, and specify a one-time
inspection of the Thomas coupling nuts, part number (P/N) MS21042L4. If
any nut is cracked, the ABTs specify replacing all nuts with nuts, P/N
NAS1805-4.
FAA's Determination
These helicopters have been approved by the aviation authority of
Italy and are approved for operation in the United States. Pursuant to
our bilateral agreement with Italy, EASA, its technical representative,
has notified us of the unsafe condition described in their AD. We are
issuing this AD because we evaluated all information provided by EASA
and determined the unsafe condition exists and is likely to exist or
develop on other helicopters of these same type designs.
AD Requirements
This AD requires, before further flight, visually inspecting each
Thomas coupling nut, P/N MS2104L4, along the tail rotor drive shaft
line for a crack. If any nut is cracked, replacing all the nuts with
nuts, P/N NAS1805-4, is required before further flight. Replacing all
nuts, P/N MS21042L4, with nuts, P/N NAS1805-4, is required within 10
hours TIS or 30 days, whichever occurs first. Finally, this AD
prohibits installing a Thomas coupling nut, P/N MS21042L4, on any tail
rotor drive shaft line.
Differences Between This AD and the EASA AD
This AD differs from the EASA AD in that we include all model
helicopters rather than limiting the applicability to specific serial-
numbered helicopters, and we do not include Model A109LUH helicopters
as they do not have a U.S. type certificate.
FAA's Justification and Determination of the Effective Date
Providing an opportunity for public comments prior to 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
prior to adoption of this rule because inspecting for and replacing a
cracked nut must be done before further flight, and replacing all nuts
is required within 10 hours TIS or 30 days, whichever occurs first,
which is a very short time period based on the average flight-hour
utilization rate of these helicopters.
Since an unsafe condition exists that requires the immediate
adoption of this AD, we determined that notice and opportunity for
prior public comment are impracticable and that good cause exists for
making this amendment effective in less than 30 days.
Comments Invited
This AD is a final rule that involves requirements affecting flight
safety and was not preceded by notice and an opportunity for public
comment. However, we invite you to send any written data, views, or
arguments about this AD. Send your comments to an address listed under
the ADDRESSES section. Include the Docket Number FAA-2013-0881 and
Directorate Identifier 2013-SW-056-AD at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of this AD. We will
consider all comments received by the closing date and may amend this
AD because of those comments.
We will post all comments we receive, without change, to <a href="http://www.regulations.gov">http://www.regulations.gov</a>, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact we
receive about this AD.
Costs of Compliance
We estimate that this AD will affect 222 helicopters of U.S.
Registry. We estimate the following costs to comply with this AD. Labor
costs are estimated at $85 per hour. We estimate 2 work hours to
inspect each nut and 16 work hours to replace all nuts at a cost of
$1,530 per helicopter and a total fleet cost of $339,600.
According to the manufacturer, the costs of this AD may be covered
under warranty, thereby reducing the cost to affected individuals. We
do not control warranty coverage for affected individuals. As a result,
we have included all costs in our cost estimate.
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 helicopters 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
[[Page 63852]]
(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):
2013-20-51 Agusta S.p.A: Amendment 39-17628; Docket No. FAA-2013-
0881; Directorate Identifier 2013-SW-056-AD.
(a) Applicability
This AD applies to the following Agusta S.p.A. (Type certificate
currently held by AgustaWestland S.p.A) (Agusta) helicopters, with a
tail rotor drive shaft flexible disc coupling (Thomas coupling) nut,
part number (P/N) MS21042L4, certificated in any category:
(i) Model A109A, A109A II, A109C, A109E, A109S, A109K2, AW109SP
helicopters; and
(ii) Model A119 and AW119 MKII helicopters.
(b) Unsafe Condition
This AD defines the unsafe condition as a production deficiency
in a certain Thomas coupling nut. This condition could result in
failure of the Thomas coupling, failure of the tail drive shaft, and
subsequent loss of control of the helicopter.
(c) Effective Date
This AD is effective October 25, 2013 to all persons except
those persons to whom it was made immediately effective by Emergency
AD 2013-20-51, issued on October 3, 2013, which contained the
requirements of this amendment.
(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
(1) Before further flight, using a borescope or light source and
mirror, inspect each Thomas coupling nut for a crack. If any Thomas
coupling nut is cracked, before further flight, replace all the
Thomas coupling nuts with nuts, P/N NAS1805-4, torqueing each nut to
5.6-7.9 Nm.
(2) Within 10 hours time-in-service or 30 days, whichever occurs
first, replace each Thomas coupling nut, P/N MS21042L4, with a nut,
P/N NAS1805-4, torqueing each nut to 5.6-7.9 Nm.
(3) After the effective date of this EAD, do not install a nut,
P/N MS21042L4, on any Thomas coupling.
(f) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Safety Management Group, FAA, may approve AMOCs
for this AD. Send your proposal to Gary Roach, Aviation Safety
Engineer, Regulations and Policy Group, Rotorcraft Directorate, FAA,
2601 Meacham Blvd., Fort Worth, TX 76137; telephone (817) 222-5110;
email <a href="/cdn-cgi/l/email-protection#84e3e5f6fdaae6aaf6ebe5e7ecc4e2e5e5aae3ebf2"><span class="__cf_email__" data-cfemail="8aedebf8f3a4e8a4f8e5ebe9e2caecebeba4ede5fc">[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) Additional Information
(1) Agusta Alert Bollettino Tecnico (ABT) No. 109K-58, ABT No.
109-136, ABT No. 109EP-130, ABT No. 109L-066, ABT No. 109S-055, ABT
No. 109SP-069, and ABT No. 119-061, all dated September 20, 2013,
which are not incorporated by reference, contain additional
information about the subject of this AD. For service information
identified in this AD, contact: Agusta Westland, Customer Support &
Services, Via Per Tornavento 15, 21019 Somma Lombardo (VA) Italy,
ATTN: Giovanni Cecchelli; telephone 39-0331-711133; fax 39 0331
711180; or at <a href="http://www.agustawestland.com/technical-bullettins">http://www.agustawestland.com/technical-bullettins</a>.
You may review a copy of the service information at the FAA, Office
of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room
663, Fort Worth, Texas 76137.
(2) The subject of this AD is addressed in European Aviation
Safety Agency (EASA) Emergency Airworthiness Directive 2013-0225-E,
effective September 21, 2013. You may view the EASA AD at <a href="http://www.regulations.gov">http://www.regulations.gov</a> in Docket No. FAA-2013-0881.
(h) Subject
Joint Aircraft Service Component (JASC): 6400 Tail rotor system.
Issued in Fort Worth, Texas, on October 16, 2013.
Kim Smith,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2013-24937 Filed 10-24-13; 8:45 am]
BILLING CODE 4910-13-P
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