AD 2011-27-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Turbomeca S.A. | Arriel 1B | Airworthiness Directives; Turbomeca Turboshaft Engines |
Unsafe Condition
Increase in hot gas ingestion and an increase of temperature in the gas generator (GG) turbine rotor, potentially resulting in turbine damage and an uncommanded in-flight shutdown.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Perform daily checks for normal GG rotor rundown time, free rotation, and no grinding noise. Inspect repaired 2nd stage turbine NGVs for non-conforming hole configuration. Replace the 2nd stage turbine NGV, 1st stage turbine disc, and 2nd stage turbine disc if non-conforming holes are found.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within specified compliance times based on accumulated GG Cycles-in-Service (CIS) as detailed in Table 1 of the AD.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Turbomeca Arriel 1B turboshaft engines with M03 modules modified by TU 76 or TU 202, and not modified by TU 148, and if fitted with a repaired 2nd stage turbine nozzle guide vane (NGV).
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 Turbomeca Arriel 1B turboshaft engines. This AD results from mandatory continuing airworthiness information (MCAI) originated 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 an increase in hot gas ingestion and an increase of temperature in the gas generator (GG) turbine rotor, potentially resulting in turbine damage and an uncommanded in-flight shutdown. We are issuing this AD to prevent over-temperature damage of the GG turbine, which could result in an uncommanded in-flight engine shutdown, and a subsequent forced autorotation landing or accident.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
This AD applies to Turbomeca Arriel 1B turboshaft engines with
M03 modules modified by TU 76 or TU 202, and not modified by TU 148,
and if fitted with a repaired 2nd stage turbine nozzle guide vane
(NGV). The M03 module contains the 2nd stage turbine NGV, 1st stage
turbine disc, and 2nd stage turbine disc. Guidance on determining if
an engine has an unrepaired 2nd stage turbine NGV installed can be
found in paragraph 1.C. of Turbomeca Mandatory Service Bulletin
(MSB) No. A292 72 0829, Version B, dated December 13, 2010.
Document Text
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[Federal Register Volume 76, Number 247 (Friday, December 23, 2011)]
[Rules and Regulations]
[Pages 80228-80230]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2011-32890]
[[Page 80228]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2010-0904; Directorate Identifier 2010-NE-33-AD;
Amendment 39-16902; AD 2011-27-01]
RIN 2120-AA64
Airworthiness Directives; Turbomeca Turboshaft Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: We are adopting a new airworthiness directive (AD) for
Turbomeca Arriel 1B turboshaft engines. This AD results from mandatory
continuing airworthiness information (MCAI) originated 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 an increase in hot gas ingestion and an increase of
temperature in the gas generator (GG) turbine rotor, potentially
resulting in turbine damage and an uncommanded in-flight shutdown. We
are issuing this AD to prevent over-temperature damage of the GG
turbine, which could result in an uncommanded in-flight engine
shutdown, and a subsequent forced autorotation landing or accident.
DATES: This AD becomes effective January 27, 2012.
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.
FOR FURTHER INFORMATION CONTACT: Rose Len, Aerospace Engineer, Engine
Certification Office, FAA, Engine & Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803; phone: (781) 238-7772;
fax: (781) 238-7199; email: <a href="/cdn-cgi/l/email-protection#1f6d706c7a31737a715f797e7e31787069"><span class="__cf_email__" data-cfemail="493b263a2c67252c27092f2828672e263f">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to include an AD that would apply to the specified products.
That NPRM was published in the Federal Register on August 31, 2011 (76
FR 54143). That NPRM proposed to correct an unsafe condition for the
specified products. The MCAI states:
During quality inspections in repair centre some 2nd stage
Nozzle Guide Vanes (NGVs) to be installed on Pre TU 148 standard
Arriel 1B were found not conforming to the definition. The affected
parts had been repaired and were found drilled on the rear flange
instead of the front flange. This configuration corresponds to 2nd
stage Turbine NGVs to be installed on post-TU 148 standard Arriel 1B
engines. This non compliance may only be found on post-TU 76
standard 2nd stage Turbine NGVs (i.e. with flexible hub).
This non compliance would increase hot gas ingestion and
generate an increase of temperature in the Gas Generator (GG)
turbine rotor, potentially resulting in turbine damage and an
uncommanded in-flight shutdown.
The corrective action includes daily checks for evidence of turbine
damage, and removal of the engine from service before further flight if
turbine damage is found. The corrective action also includes inspecting
the configuration of the holes in the repaired 2nd stage turbine NGV.
If the holes are non-conforming, then before further flight replacement
of the 2nd stage turbine NGV, 1st stage turbine disc, and 2nd stage
turbine disc, with discs eligible for installation, is required. You
may obtain further information by examining the MCAI in the AD docket.
Comments
We gave the public the opportunity to participate in developing
this AD. We received no comments on the NPRM.
Conclusion
We reviewed the available data and determined that air safety and
the public interest require adopting the AD as proposed.
Costs of Compliance
Based on the service information, we estimate that this AD affects
about 20 Turbomeca Arriel 1B turboshaft engines installed on
helicopters of U.S. registry. We estimate that it will take about 40
work-hours per engine to inspect a repaired 2nd stage turbine NGV for
the non-conforming hole configuration. We also estimate that it will
take about 60 work-hours to replace the NGV, the 1st stage turbine
disc, and the 2nd stage turbine disc, and that one engine will require
these replacements. The average labor rate is $85 per work-hour.
Required parts cost about $19,889 per engine. Based on these figures,
we estimate the cost of the AD on U.S. operators to be $92,989. Our
cost estimate is exclusive of possible warranty coverage.
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.
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 provided in the
ADDRESSES section. Comments will be available in the AD docket shortly
after receipt.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
[[Page 80229]]
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:
2011-27-01 Turbomeca: Amendment 39-16902; Docket No. FAA-2010-0904;
Directorate Identifier 2010-NE-33-AD.
(a) Effective Date
This airworthiness directive (AD) becomes effective January 27,
2012.
(b) Affected ADs
None.
(c) Applicability
This AD applies to Turbomeca Arriel 1B turboshaft engines with
M03 modules modified by TU 76 or TU 202, and not modified by TU 148,
and if fitted with a repaired 2nd stage turbine nozzle guide vane
(NGV). The M03 module contains the 2nd stage turbine NGV, 1st stage
turbine disc, and 2nd stage turbine disc. Guidance on determining if
an engine has an unrepaired 2nd stage turbine NGV installed can be
found in paragraph 1.C. of Turbomeca Mandatory Service Bulletin
(MSB) No. A292 72 0829, Version B, dated December 13, 2010.
(d) Reason
This AD was prompted by an increase in hot gas ingestion and an
increase of temperature in the gas generator (GG) turbine rotor,
potentially resulting in turbine damage and an uncommanded in-flight
shutdown. We are issuing this AD to prevent over-temperature damage
of the GG turbine, which could result in an uncommanded in-flight
engine shutdown, and a subsequent forced autorotation landing or
accident.
(e) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(f) Daily Checks
(1) Starting from the effective date of this AD, perform a daily
check (after last flight of the day) for:
(i) Normal rundown time of the GG rotor; and
(ii) The free rotation of the GG rotor; and
(iii) No grinding noise during the rundown check, and during the
free rotation check of the GG rotor.
(2) Guidance on performing the daily checks can be found in the
Maintenance Manual, task 71-02-09-760-801 and task 05-20-01-200-801.
(3) If the engine fails any of these daily checks, remove the
engine from service before further flight.
(g) Inspection of Repaired 2nd Stage Turbine NGVs
(1) Inspect the 2nd stage turbine NGV for a non-conforming hole
configuration, at the compliance times in Table 1 of this AD.
Guidance on 2nd stage turbine NGV non-conforming hole configuration
can be found in Turbomeca MSB No. A292 72 0829, Version B, dated
December 13, 2010.
Table 1--Inspection Compliance Times
------------------------------------------------------------------------
If accumulated GG Cycles-in-Service
(CIS) on the effective date of this AD Then inspect:
are:
------------------------------------------------------------------------
(i) Fewer than 1,200 CIS on both the Before exceeding 1,500 GG CIS.
1st and 2nd stage turbines.
(ii) 1,200 or more but fewer than 1,800 Before exceeding 300 GG CIS
CIS on either the 1st or 2nd stage after the effective date of
turbines. this AD but not to exceed
2,000 CIS on either the 1st or
2nd stage turbines.
(iii) 1,800 or more but fewer than Before exceeding 200 GG CIS
2,400 CIS on either the 1st or 2nd after the effective date of
stage turbine. this AD but not to exceed
2,500 CIS on either the 1st or
2nd stage turbines.
(iv) Greater than 2,400 CIS on either Before exceeding 100 GG CIS
the 1st or 2nd stage turbine. after the effective date of
this AD but not to exceed
3,000 CIS on either the 1st or
2nd stage turbine.
------------------------------------------------------------------------
(2) If the configuration of the holes in the repaired 2nd stage
turbine NGV are conforming, then no further action is required.
(3) If the configuration of the holes in the repaired 2nd stage
turbine NGV are non-conforming, then before further flight:
(i) Replace the 2nd stage turbine NGV with a 2nd stage turbine
NGV eligible for installation; and
(ii) Replace the 1st stage turbine disc and 2nd stage turbine
disc with discs eligible for installation.
(h) Terminating Action
Complying with paragraph (g)(1) and either paragraph (g)(2) or
paragraphs (g)(3)(i) through (g)(3)(ii) of this AD, or replacing the
M03 module with an M03 module that is eligible for installation, is
terminating action for the requirements of this AD.
(i) Installation Prohibition
(1) Do not reinstall the 1st stage turbine disc and the 2nd
stage turbine disc removed in paragraph (g)(3)(ii) of this AD into
any engine.
(2) After the effective date of this AD, do not install an M03
module that has incorporated TU 202 but not incorporated TU 148,
unless the module is in compliance with the requirements of this AD.
(3) After the effective date of this AD, do not install an M03
module that has incorporated TU 76 but not incorporated TU 148,
unless the module is in compliance with the requirements of this AD.
(j) FAA AD Differences
(1) This AD differs from the Mandatory Continuing Airworthiness
Information (MCAI) and/or service information as follows:
(i) This AD does not require sending data to Turbomeca to
confirm whether Turbomeca MSB No. A292 72 0829, Version B, dated
December 13, 2010, is applicable to the operator's engine; the MCAI
does.
(ii) This AD does not incorporate by reference (IBR) Turbomeca
MSB No. A292 72 0829, Version B, dated December 13, 2010; the MCAI
does.
(iii) This AD requires replacing non-conforming 2nd stage
turbine NGVs and 1st stage and 2nd stage turbine discs that were
operated with non-conforming 2nd stage turbine NGVs but does not
require replacing affected M03 modules. The MCAI requires replacing
affected M03 modules with M03 modules eligible for installation.
(k) Definition
For the purpose of this AD, a conforming repaired 2nd stage
turbine NGV is one with cooling holes in the forward inner flange,
and with no cooling holes in the rear flange.
(l) Alternative Methods of Compliance (AMOCs)
The Manager, Engine Certification Office, FAA, has the authority
to approve AMOCs for this AD, if requested using the procedures
found in 14 CFR 39.19.
(m) Related Information
(1) Refer to European Aviation Safety Agency AD 2010-0273R1,
dated February 16, 2011, and Turbomeca MSB No. A292 72 0829, Version
B, dated December 13, 2010, for related information. Contact
Turbomeca, 40220 Tarnos, France; phone: 33 05 59 74 40 00; fax: 33
05 59 74 45 15; for a copy of this service information.
(2) Contact Rose Len, Aerospace Engineer, Engine Certification
Office, FAA, Engine & Propeller Directorate, 12 New England
Executive Park, Burlington, MA 01803; phone: (781) 238-7772; fax:
(781) 238-7199; email: <a href="/cdn-cgi/l/email-protection#bdcfd2ced893d1d8d3fddbdcdc93dad2cb"><span class="__cf_email__" data-cfemail="8af8e5f9efa4e6efe4caecebeba4ede5fc">[email protected]</span></a>, for more information about
this AD.
[[Page 80230]]
(n) Material Incorporated by Reference
None.
Issued in Burlington, Massachusetts, on December 16, 2011.
Peter A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification
Service.
[FR Doc. 2011-32890 Filed 12-22-11; 8:45 am]
BILLING CODE 4910-13-P
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