AD 2008-08-16
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Turbomeca S.A. | Makila 1A | Airworthiness Directives; Turbomeca Makila 1A and 1A1 Turboshaft Engines |
| engine | Turbomeca S.A. | Makila 1A1 | Airworthiness Directives; Turbomeca Makila 1A and 1A1 Turboshaft Engines |
Unsafe Condition
Recent unexplained reversions of the ECU to the 65% N1 back-up mode due to temporary loss of N2 speed signal could lead to inability to continue safe flight, emergency autorotation landing, or an accident.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace the selector-comparator board in the ECU with a board incorporating Turbomeca modification TU 250.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Turbomeca Makila 1A and 1A1 turboshaft engines.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
The FAA is superseding an existing airworthiness directive (AD) for Turbomeca Makila 1A, 1A1, and 1A2 turboshaft engines. That AD currently requires replacing certain digital electronic control units (DECUs) and electronic control units (ECUs) with modified DECUs and ECUs. This AD applies only to Makila 1A and 1A1 turboshaft engines, and requires replacing the selector-comparator board in the ECU with a board incorporating Turbomeca modification TU 250. This AD results from recent unexplained reversions of the ECU to the 65% N1 back-up mode. We are issuing this AD to prevent dual-engine continued operation at 65% N1 after reversion of the ECU to the 65% N1 back-up mode due to temporary loss of N2 speed signal, which could lead to inability to continue safe flight, emergency autorotation landing, or an accident.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 73, Number 74 (Wednesday, April 16, 2008)]
[Rules and Regulations]
[Pages 20525-20526]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: E8-8083]
========================================================================
Rules and Regulations
Federal Register
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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.
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Federal Register / Vol. 73, No. 74 / Wednesday, April 16, 2008 /
Rules and Regulations
[[Page 20525]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2007-0157; Directorate Identifier 2001-NE-23-AD;
Amendment 39-15469; AD 2008-08-16]
RIN 2120-AA64
Airworthiness Directives; Turbomeca Makila 1A and 1A1 Turboshaft
Engines
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The FAA is superseding an existing airworthiness directive
(AD) for Turbomeca Makila 1A, 1A1, and 1A2 turboshaft engines. That AD
currently requires replacing certain digital electronic control units
(DECUs) and electronic control units (ECUs) with modified DECUs and
ECUs. This AD applies only to Makila 1A and 1A1 turboshaft engines, and
requires replacing the selector-comparator board in the ECU with a
board incorporating Turbomeca modification TU 250. This AD results from
recent unexplained reversions of the ECU to the 65% N1 back-up mode. We
are issuing this AD to prevent dual-engine continued operation at 65%
N1 after reversion of the ECU to the 65% N1 back-up mode due to
temporary loss of N2 speed signal, which could lead to inability to
continue safe flight, emergency autorotation landing, or an accident.
DATES: This AD becomes effective May 21, 2008.
ADDRESSES: The Docket Operations office is located at Docket Management
Facility, U.S. Department of Transportation, 1200 New Jersey Avenue,
SE., West Building Ground Floor, Room W12-140, Washington, DC 20590-
0001.
You can get the service information identified in this AD from
Turbomeca, 40220 Tarnos, France; telephone (33) 05 59 74 40 00; fax
(33) 05 59 74 45 15.
FOR FURTHER INFORMATION CONTACT: James Lawrence, Aerospace Engineer,
Engine Certification Office, FAA, Engine and Propeller Directorate, 12
New England Executive Park, Burlington, MA 01803; e-mail:
<a href="/cdn-cgi/l/email-protection#365c575b5345185a574144535855537650575718515940"><span class="__cf_email__" data-cfemail="157f747870663b79746267707b7670557374743b727a63">[email protected]</span></a>; telephone (781) 238-7176; fax (781) 238-7199.
SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39 by
superseding AD 2002-15-05, Amendment 39-12833 (67 FR 49859, August 1,
2002), with a proposed AD. The proposed AD applies to Turbomeca Makila
1A and 1A1 turboshaft engines. We published the proposed AD in the
Federal Register on November 15, 2007 (72 FR 64172). That action
proposed to require replacing the selector-comparator board in the ECU
with a board incorporating Turbomeca modification TU 250.
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 (telephone (800) 647-5527) is provided in
the ADDRESSES section. Comments will be available in the AD docket
shortly after receipt.
Comments
We provided the public the opportunity to participate in the
development of this AD. We received no comments on the proposal or on
the determination of the cost to the public. We also found we needed to
clarify the unsafe condition statement from ``We are issuing this AD to
prevent dual-engine reversion of the ECU to the 65% N1 back-up mode,
which could lead to inability to continue safe flight, emergency
autorotation landing, or an accident'' to ``We are issuing this AD to
prevent dual-engine continued operation at 65% N1 after reversion of
the ECU to the 65% N1 back-up mode due to temporary loss of N2 speed
signal, which could lead to inability to continue safe flight,
emergency autorotation landing, or an accident''.
Conclusion
We have carefully reviewed the available data and determined that
air safety and the public interest require adopting the AD with the
change described previously.
Makila 1A2 Turboshaft Engines Excluded From This AD
Although Makila 1A2 turboshaft engines, which were also listed in
the previous AD, might be affected by this unsafe condition, EASA is
reviewing the need to mandate a corrective action. Depending on the
review outcome, we might address those engines in another AD action.
Costs of Compliance
We estimate that this AD will affect 10 Makila 1A and 1A1
turboshaft engines installed on helicopters of U.S. registry. We also
estimate that it will take about 1 work-hour per engine to perform the
actions, and that the average labor rate is $80 per work-hour. Required
parts will cost about $3,500 per engine. Based on these figures, we
estimate the total cost of the AD to U.S. operators to be $35,800.
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
[[Page 20526]]
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); 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 summary of the costs to comply with this AD and
placed it in the AD Docket. You may get a copy of this summary at the
address listed under ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
Adoption of the Amendment
0
Accordingly, under the authority delegated to me by the Administrator,
the Federal Aviation Administration 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 Amendment 39-12833 (67 FR
49859, August 1, 2002), and by adding a new airworthiness directive,
Amendment 39-15469, to read as follows:
2008-08-16 Turbomeca: Amendment 39-15469. Docket No. FAA-2007-0157;
Directorate Identifier 2001-NE-23-AD.
Effective Date
(a) This airworthiness directive (AD) becomes effective May 21,
2008.
Affected ADs
(b) This AD supersedes AD 2002-15-05, Amendment 39-12833.
Applicability
(c) This AD applies to Turbomeca Makila 1A and 1A1 turboshaft
engines. These engines are installed on, but not limited to,
Eurocopter France model AS 332C, AS 332L, and AS 332L1 helicopters.
Unsafe Condition
(d) This AD results from recent unexplained reversions of the
electronic control unit (ECU) to the 65% N1 back-up mode. The
actions specified in this AD are intended to prevent dual-engine
continued operation at 65% N1 after reversion of the ECU to the 65%
N1 back-up mode due to temporary loss of N2 speed signal, which
could lead to inability to continue safe flight, emergency
autorotation landing, or an accident.
Compliance
(e) You are responsible for having the actions required by this
AD performed before June 30, 2008, unless the actions have already
been done.
(f) Replace the selector-comparator board in the ECU with a
board incorporating Turbomeca Modification TU 250. Information on
Modification TU 250 can be found in Turbomeca Mandatory Service
Bulletin No. 298 73 0250, dated March 23, 2007.
Alternative Methods of Compliance
(g) The Manager, Engine Certification Office, FAA, has the
authority to approve alternative methods of compliance for this AD
if requested using the procedures found in 14 CFR 39.19.
Related Information
(h) European Aviation Safety Agency AD 2007-0144, dated May 18,
2007, also addresses the subject of this AD.
(i) Contact James Lawrence, Aerospace Engineer, Engine
Certification Office, FAA, Engine and Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803; e-mail:
<a href="/cdn-cgi/l/email-protection#214b404c44520f4d405653444f4244614740400f464e57"><span class="__cf_email__" data-cfemail="acc6cdc1c9df82c0cddbdec9c2cfc9eccacdcd82cbc3da">[email protected]</span></a>; telephone (781) 238-7176; fax (781) 238-
7199, for more information about this AD.
Issued in Burlington, Massachusetts, on April 8, 2008.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. E8-8083 Filed 4-15-08; 8:45 am]
BILLING CODE 4910-13-P
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