AD 2011-24-08
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Aviat | Various | Airworthiness Directives; Turbomeca S.A. Makila 1A2 Turboshaft Engines |
| engine | Turbomeca | S | Airworthiness Directives; Turbomeca S.A. Makila 1A2 Turboshaft Engines |
Unsafe Condition
An N2 (power turbine speed) sensor harness wire crimping discrepancy can lead to inadvertent activation of the 65% N1 back up control mode, resulting in significant power loss on one or more engines, potentially causing an emergency landing.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace affected N2 sensor harnesses with serviceable parts. Prohibit installation of non-serviceable N2 sensor harnesses on engines.
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Compliance Time
Within 12 months of effective date
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Affected Aircraft
Turbomeca S.A. Makila 1A2 turboshaft engines, all serial numbers. Specifically affected are N2 sensor Part Number 0 301 52 001 0 with Serial Numbers between S/N 242 and S/N 339 inclusive.
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 the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
This AD applies to Makila 1A2 turboshaft engines, all serial
numbers.
Document Text
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[Federal Register Volume 76, Number 225 (Tuesday, November 22, 2011)]
[Rules and Regulations]
[Pages 72091-72093]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2011-30061]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2011-1037; Directorate Identifier 2011-NE-30-AD;
Amendment 39-16872; AD 2011-24-08]
RIN 2120-AA64
Airworthiness Directives; Turbomeca S.A. Makila 1A2 Turboshaft
Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
-----------------------------------------------------------------------
SUMMARY: We are adopting a new airworthiness directive (AD) for the
products listed above. This AD results from mandatory continuing
airworthiness information (MCAI) issued by an aviation authority of
another country to identify and correct an unsafe condition on an
aviation product. The MCAI describes the unsafe condition as:
A helicopter experienced an inadvertent activation of the 65% N1
(gas generator speed) back up control mode.
The subsequent technical investigations carried by Turbomeca
revealed that an N2 (power turbine speed) sensor harness wire
crimping discrepancy was at the origin of this event. Further
quality investigations performed with the supplier led to the
conclusion that N2 sensor Part Number (P/N) 0 301 52 001 0 whose
Serial Numbers (S/N) are between S/N 242 and S/N 339 inclusive are
potentially concerned by the same manufacturing discrepancy.
This condition, if not corrected, could lead to the inadvertent
activation of the 65% N1 back up mode and consequently to
significant power loss on one or more or both engines installed on
the same helicopter, potentially resulting in an emergency landing
of the helicopter.
We are issuing this AD to prevent inadvertent activation of the backup
control mode, which could result in engine power loss and emergency
landing of the helicopter.
DATES: This AD becomes effective December 7, 2011.
[[Page 72092]]
We must receive comments on this AD by December 22, 2011.
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> and follow the instructions for sending your
comments electronically.
<bullet> Mail: U.S. Department of Transportation, 1200 New Jersey
Avenue SE., West Building Ground Floor, Room W12-140, Washington, DC
20590-0001.
<bullet> Hand Delivery: Deliver to Mail address above between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
<bullet> Fax: (202) 493-2251.
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 regulatory evaluation,
any comments received, and other information. The street address for
the Docket Operations office (phone: (800) 647-5527) is the same as the
Mail address provided in the ADDRESSES section. Comments will be
available in the AD docket shortly after receipt.
FOR FURTHER INFORMATION CONTACT: James Lawrence, Aerospace Engineer,
Engine Certification Office, FAA, Engine & Propeller Directorate, 12
New England Executive Park, Burlington, MA 01803; email:
<a href="/cdn-cgi/l/email-protection#82e8e3efe7f1aceee3f5f0e7ece1e7c2e4e3e3ace5edf4"><span class="__cf_email__" data-cfemail="385259555d4b1654594f4a5d565b5d785e5959165f574e">[email protected]</span></a>; phone: (781) 238-7176; fax: (781) 238-7199.
SUPPLEMENTARY INFORMATION:
Discussion
The European Aviation Safety Agency (EASA), which is the Technical
Agent for the Member States of the European Community, issued EASA
Airworthiness Directive 2011-0147, dated August 5, 2011 (referred to
after this as ``the MCAI''), to correct an unsafe condition for the
specified products. The MCAI states:
A helicopter experienced an inadvertent activation of the 65% N1
(gas generator speed) back up control mode.
The subsequent technical investigations carried by Turbomeca
revealed that an N2 (power turbine speed) sensor harness wire
crimping discrepancy was at the origin of this event. Further
quality investigations performed with the supplier led to the
conclusion that N2 sensor Part Number (P/N) 0 301 52 001 0 whose
Serial Numbers (S/N) are between S/N 242 and S/N 339 inclusive are
potentially concerned by the same manufacturing discrepancy.
This condition, if not corrected, could lead to the inadvertent
activation of the 65% N1 back up mode and consequently to
significant power loss on one or more or both engines installed on
the same helicopter, potentially resulting in an emergency landing
of the helicopter.
For the reasons described above, this AD requires replacement of
affected N2 sensor harnesses with serviceable parts. This AD also
prohibits the installation of non serviceable N2 sensor harnesses on
an engine.
You may obtain further information by examining the MCAI in the AD
docket.
Relevant Service Information
Turbomeca has issued Service Bulletin 298 77 0817, Version B, dated
August 23, 2011. The actions described in this service information are
intended to correct the unsafe condition identified in the MCAI.
FAA's Determination and Requirements of This AD
This product has been approved by the aviation authority of France
and is approved for operation in the United States. Pursuant to our
bilateral agreement with the European Community, EASA has notified us
of the unsafe condition described in the MCAI and service information
referenced above. 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 products of the same type
design. This AD requires replacement of the affected N2 sensor
harnesses with N2 sensor harnesses eligible for installation.
FAA's Determination of the Effective Date
Since no domestic operators use this product, notice and
opportunity for public comment before issuing this AD are unnecessary.
Therefore, we are adopting this regulation immediately.
Comments Invited
This AD is a final rule that involves requirements affecting flight
safety, and we did not precede it by notice and opportunity for public
comment. We invite you to send any written relevant data, views, or
arguments about this AD. Send your comments to an address listed under
the ADDRESSES section. Include ``Docket No. FAA-2011-1037; Directorate
Identifier 2011-NE-30-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
with FAA personnel concerning this AD. Using the search function of the
Web site, anyone can find and read the comments in any of our dockets,
including, if provided, the name of the individual who sent the comment
(or signed the comment on behalf of an association, business, labor
union, etc.). You may review the DOT's complete Privacy Act Statement
in the Federal Register published on April 11, 2000 (65 FR 19477-78).
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 above, I certify this AD:
1. Is not a ``significant regulatory action'' under Executive Order
12866,
2. Is not a ``significant rule'' under the DOT Regulatory Policies
and Procedures (44 FR 11034, February 26, 1979), and
3. 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 a regulatory evaluation of the estimated costs to
comply with this AD and placed it in the AD docket.
[[Page 72093]]
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 AD:
2011-24-08 Turbomeca S.A.: Amendment 39-16872; Docket No. FAA-2011-
1037; Directorate Identifier 2011-NE-30-AD.
(a) Effective Date
This airworthiness directive (AD) becomes effective December 7,
2011.
(b) Affected ADs
None.
(c) Applicability
This AD applies to Makila 1A2 turboshaft engines, all serial
numbers.
(d) Reason
(1) This AD results from mandatory continuing airworthiness
information (MCAI) issued by an aviation authority of another
country to identify and correct an unsafe condition on an aviation
product. The MCAI describes the unsafe condition as:
A helicopter experienced an inadvertent activation of the 65% N1
(gas generator speed) back up control mode.
The subsequent technical investigations carried by Turbomeca
revealed that an N2 (power turbine speed) sensor harness wire
crimping discrepancy was at the origin of this event. Further
quality investigations performed with the supplier led to the
conclusion that N2 sensor Part Number (P/N) 0 301 52 001 0 whose
Serial Numbers (S/N) are between S/N 242 and S/N 339 inclusive are
potentially concerned by the same manufacturing discrepancy.
This condition, if not corrected, could lead to the inadvertent
activation of the 65% N1 back up mode and consequently to
significant power loss on one or more or both engines installed on
the same helicopter, potentially resulting in an emergency landing
of the helicopter.
(2) We are issuing this AD to prevent inadvertent activation of
the backup control mode, which could result in engine power loss and
emergency landing of the helicopter.
(e) Actions and Compliance
(1) Unless already done, do the following actions.
(2) For engines equipped with N2 sensor harnesses, P/N 0 301 52
001 0, whose S/Ns are between S/N 242 and S/N 339 inclusive, do the
following:
(i) If an affected P/N is installed on each of the 2 (two)
engines of the helicopter, then within 10 flight hours (FHs) after
the effective date of this AD, replace one N2 sensor harness with an
N2 sensor harness that is eligible for installation, and within 50
FHs after the effective date of this AD, replace the second harness
with an N2 sensor harness that is eligible for installation.
(ii) If an affected P/N is installed only on 1 (one) engine of
the helicopter, then within 50 FHs after the effective date of this
AD, replace the affected N2 sensor harness with an N2 harness that
is eligible for installation.
(3) After the effective date of this AD, do not install in an
engine any N2 sensor harness, P/N 0 301 52 001 0, whose S/N is
between S/N 242 and S/N 339 inclusive, unless the part has ``SB
0815'' marked on the identification plate.
(4) After the effective date of this AD, do not install in a
helicopter an engine equipped with an N2 sensor harness, P/N 0 301
52 001 0, whose S/N is between S/N 242 and S/N 339 inclusive, unless
the part has ``SB 0815'' marked on the identification plate.
(f) Alternative Methods of Compliance (AMOCs)
The Manager, Engine Certification Office, FAA, may approve AMOCs
for this AD. Use the procedures found in 14 CFR 39.19 to make your
request.
(g) Related Information
(1) Refer to MCAI EASA AD 2011-0147, dated August 5, 2011, and
Turbomeca Service Bulletin No. 298 77 0817, for related information.
Contact Turbomeca; 40220 Tarnos, France; phone: 33-05-59-74-40-00;
fax: 33-05-59-74-45-11; for a copy of this service information.
(2) Contact James Lawrence, Aerospace Engineer, Engine
Certification Office, FAA, Engine & Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803; email:
<a href="/cdn-cgi/l/email-protection#e88289858d9bc684899f9a8d868b8da88e8989c68f879e"><span class="__cf_email__" data-cfemail="345e555951471a58554346515a5751745255551a535b42">[email protected]</span></a>; phone: (781)-238-7176; fax: (781) 238-7199,
for more information about this AD.
(h) Material Incorporated by Reference
None.
Issued in Burlington, Massachusetts, on November 9, 2011.
Peter A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification
Service.
[FR Doc. 2011-30061 Filed 11-21-11; 8:45 am]
BILLING CODE 4910-13-P
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