
[Federal Register Volume 76, Number 138 (Tuesday, July 19, 2011)]
[Proposed Rules]
[Pages 42610-42612]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-18171]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0710; Directorate Identifier 2010-NE-26-AD]
RIN 2120-AA64


Airworthiness Directives; Turbomeca Arriel 1 Series Turboshaft 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to revise an existing airworthiness directive (AD) 
that applies to the products listed above. The existing AD currently 
requires removing from service certain gas generator second stage 
turbine discs, part number (P/N) 0 292 25 040 0, that are not marked 
with ``CFR'' before the discs exceed 2,500 cycles-in-service (CIS) 
since-new or within 20 CIS from the effective date of the AD, whichever 
occurs later. That AD also requires removing from service certain gas 
generator second stage turbine discs, P/N 0 292 25 040 0, that are 
marked with ``CFR'' before the discs exceed 3,500 CIS since-new. Since 
we issued that AD, Turbomeca has restored all or part of the life 
limits of the affected discs, and the European Aviation Safety Agency 
(EASA) issued AD 2010-0101R2, dated March 24, 2011 to do the same. This 
proposed AD would still prevent disc failure but extends the life 
limits of the affected discs. We are proposing this AD to prevent 
failure of the gas generator second stage turbine disc which could 
result in the release of high energy debris and damage to the 
helicopter.

[[Page 42611]]


DATES: We must receive comments on this proposed AD by September 2, 
2011.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     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.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact Turbomeca, 
40220 Tarnos, France; phone: 33 05 59 74 40 00, fax: 33 05 59 74 45 15. 
You may review copies of the referenced service information at the FAA, 
Engine & Propeller Directorate, 12 New England Executive Park, 
Burlington, MA. For information on the availability of this material at 
the FAA, call 781-238-7125.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (phone: 800-647-5527) is in the ADDRESSES 
section. Comments will be available in the AD docket shortly after 
receipt.

FOR FURTHER INFORMATION CONTACT: Rose Len, Aerospace Engineer, Engine 
Certification Office, FAA, 12 New England Executive Park, Burlington, 
MA 01803; phone: 781-238-7772; fax: 781-238-7199; e-mail: 
rose.len@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2010-0710; 
Directorate Identifier 2010-NE-26-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    On September 10, 2010, we issued AD 2010-19-06, Amendment 39-16434 
(75 FR 57371, September 21, 2010), for Turbomeca Arriel 1 series 
turboshaft engines. That AD requires removing from service gas 
generator second stage turbine discs, P/N 0 292 25 040 0 that do not 
have the ``CFR'' marking, before exceeding 2,500 CIS since-new or 
within 20 CIS from the effective date of the AD, whichever occurs 
later. That AD also requires removing from service gas generator second 
stage turbine discs, P/N 0 292 25 040 0 that have the ``CFR'' marking, 
before exceeding 3,500 CIS since-new. Discs that have the ``CFR'' 
marking have been inspected using a ``reinforced'' eddy-current 
inspection (ECI). Discs that do not have the ``CFR'' marking have not 
been inspected using the ``reinforced'' ECI. Based on the 
``reinforced'' ECI and additional analysis finding performed by 
Turbomeca, the discs with the ``CFR'' marking are compliant with their 
original published life limit of 6,500 CIS since-new, and the life 
limit of discs with no ``CFR'' marking can be increased to 4,000 CIS 
since-new. AD 2010-19-06 resulted 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. We issued that AD to prevent failure of the gas 
generator second stage turbine disc which could result in the release 
of high energy debris and damage to the helicopter.

Actions Since Existing AD Was Issued

    Since we issued AD 2010-19-06, Turbomeca has restored all or part 
of the life limits of the affected discs, based on the reinforced eddy 
current inspection that provides an improved detection threshold of any 
metallurgical non-conformities in the discs, in combination with 
additional testing and analysis.
    Also since we issued AD 2010-19-06, EASA has issued MCAI AD 2010-
0101R2, dated March 24, 2011, which, for gas generator second stage 
turbine discs, P/N 0 292 25 040 0 that do not have the ``CFR'' marking, 
increases the life limit to 4,000 cycles, and for gas generator second 
stage turbine discs, P/N 0 292 25 040 0 that have the ``CFR'' marking, 
returns the life limit to the original published life limit of 6,500 
cycles.

FAA's Determination

    We are proposing 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 the same type design.

Proposed AD Requirements

    This proposed AD would require removing gas generator second stage 
turbine discs, P/N 0 292 25 040 0 that do not have the ``CFR'' marking, 
from service before exceeding 4,000 CIS since-new. This proposed AD 
would also require removing gas generator second stage turbine discs, 
P/N 0 292 25 040 0 that have the ``CFR'' marking, from service before 
exceeding 6,500 CIS since-new.

Costs of Compliance

    We estimate that this proposed AD would affect 203 Turbomeca Arriel 
1 series turboshaft engines on helicopters of U.S. registry. We 
estimate that no additional labor costs would be incurred to return 
part of the life limit of the discs that do not have the ``CFR'' 
marking, to the original published life limit. Based on these figures, 
we estimate the total cost of the proposed AD to U.S. operators to be 
$0.

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 proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would not 
have a substantial direct effect on the States, on the relationship 
between the

[[Page 42612]]

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 the proposed 
regulation:
    (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),
    (3) Will not affect intrastate aviation in Alaska, 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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    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]

    2. The FAA amends Sec.  39.13 by removing airworthiness directive 
(AD) 2010-19-06, Amendment 39-16434 (75 FR 57371 September 21, 2010), 
and adding the following new AD:

Turbomeca: Docket No. FAA-2010-0710; Directorate Identifier 2010-NE-
26-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by September 2, 
2011.

(b) Affected ADs

    This AD revises AD 2010-19-06, Amendment 39-16434.

(c) Applicability

    This AD applies to Turbomeca Arriel 1A, 1A1, 1B, 1C, 1C1, 1C2, 
1D, 1D1, and 1S1 turboshaft engines that have incorporated 
Modification TU347.

(d) Unsafe Condition

    This AD was prompted by Turbomeca restoring all or part of the 
life limits of the affected discs. We are issuing this AD to prevent 
failure of the gas generator second stage turbine disc which could 
result in the release of high energy debris and damage to the 
helicopter.

(e) Compliance

    (1) Comply with this AD within the compliance times specified, 
unless already done.
    (2) Remove from service gas generator second stage turbine 
discs, part number (P/N) 0 292 25 040 0 that do not have the ``CFR'' 
marking, before exceeding 4,000 cycles-in-service (CIS) since-new.
    (3) Remove from service gas generator second stage turbine 
discs, P/N 0 292 25 040 0 that have the ``CFR'' marking, before 
exceeding 6,500 CIS since-new.

(4) Gas Generator Second Stage Turbine Installation Prohibition

    (i) After the effective date of this AD, do not install into any 
engine gas generator second stage turbine discs, P/N 0 292 25 040 0 
that do not have the ``CFR'' marking, and have 4,000 or more CIS 
since-new.
    (ii) After the effective date of this AD, do not install into 
any engine gas generator second stage turbine discs, P/N 0 292 25 
040 0 that have the ``CFR'' marking, and have 6,500 or more CIS 
since-new.

(f) 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.

(g) Related Information

    (1) Refer to Turbomeca Alert Mandatory Service Bulletin No. A292 
72 0831, Version C, dated March 3, 2011, 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) You may review copies of the referenced service information 
at the FAA, Engine & Propeller Directorate, 12 New England Executive 
Park, Burlington, MA. For information on the availability of this 
material at the FAA, call 781-238-7125.
    (3) For more information about this AD, contact Rose Len, 
Aerospace Engineer, Engine Certification Office, FAA, 12 New England 
Executive Park, Burlington, MA 01803; phone: 781-238-7772; fax: 781-
238-7199; e-mail: rose.len@faa.gov.

(h) Material Incorporated by Reference

    None.

    Issued in Burlington, Massachusetts, on July 13, 2011.
Colleen M. D'Alessandro,
Acting Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.

[FR Doc. 2011-18171 Filed 7-18-11; 8:45 am]
BILLING CODE 4910-13-P


