
[Federal Register Volume 77, Number 106 (Friday, June 1, 2012)]
[Proposed Rules]
[Pages 32437-32439]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-13324]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0115; Directorate Identifier 2010-NE-40-AD]
RIN 2120-AA64


Airworthiness Directives; Turbomeca S.A. Turboshaft Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: We propose to supersede an existing airworthiness directive 
(AD) that applies to certain Turbomeca S.A. Arriel 2B and 2B1 
turboshaft engines. The existing AD currently requires accomplishment 
of the TU166 modification. Since we issued that AD, we became aware of 
an accident involving an engine in-flight shutdown on a twin-engine 
helicopter powered by two Arriel 2S2 engines. This proposed AD would 
add the Arriel 2S2 engine to the applicability of engines requiring the 
TU166 modification with a different compliance time. We are proposing 
this AD to prevent rupture of a gas generator (GG) turbine blade, which 
could result in an uncommanded in-flight shutdown and a forced landing 
or accident.

DATES: We must receive comments on this proposed AD by July 31, 2012.

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 (0)5 59 74 40 00; telex: 570 042; fax: 
33 (0)5 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, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; phone: 781-238-7772; fax: 
781-238-7199; email: 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-2011-0115; 
Directorate Identifier 2010-NE-40-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 June 14, 2011, we issued AD 2011-13-05, Amendment 39-16728 (76 
FR 40222, July 8, 2011) for Turbomeca S.A. Arriel 2B and 2B1 turboshaft 
engines not modified by the TU166 modification. That AD requires 
accomplishment of the TU166 modification when the GG turbine is 
replaced or when the engine or Module M03 is going through overhaul or 
repair, or within 1,300 cycles-in-service after the effective date of 
that AD, whichever occurs first. That AD resulted from several cases of 
GG turbine blade rupture occurring in service on Arriel 2 twin-engine 
powered helicopters, and one case on a single-engine powered 
helicopter. We issued that AD to prevent rupture of a GG turbine blade,

[[Page 32438]]

which could result in an uncommanded in-flight shutdown and an 
emergency autorotation landing or accident on single-engine powered 
helicopters.

Actions Since Existing AD Was Issued

    Since we issued AD 2011-13-05, Amendment 39-16728 (76 FR 40222, 
July 8, 2011), an accident occurred on a Sikorsky S-76C++ twin-engine 
helicopter following an uncommanded in-flight shutdown of one of its 
Arriel 2S2 turboshaft engines. That engine did not have the TU166 
modification incorporated. The European Aviation Safety Agency (EASA), 
which is the Technical Agent for the Member States of the European 
Community, has superseded EASA AD 2010-0198, dated October 1, 2010, 
which we reference in AD 2011-13-05. The EASA superseding AD, AD 2012-
0054, dated April 2, 2012, adds the Arriel 2S2 turboshaft engine to the 
applicability for incorporating the TU166 modification with its own 
compliance time. This AD adds the Arriel 2S2 engine with a compliance 
time different than the Arriel 2B and 2B1 engines.

Relevant Service Information

    We reviewed Turbomeca S.A. Alert Mandatory Service Bulletin (MSB) 
No. A292 72 3166 Version B, dated September 20, 2010, and Alert MSB No. 
A292 72 4166 Version A, dated March 23, 2012. The Alert MSBs describe 
procedures for accomplishing the TU166 modification.

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 retain all of the requirements of AD 2011-
13-05, Amendment 39-16728 (76 FR 40222, July 8, 2011) except it would 
reduce the compliance time for the Arriel 2B and 2B1 engines to account 
for the effective date of that AD. This proposed AD would add the 
Arriel 2S2 turboshaft engine to the AD applicability and would add 
accomplishing the TU166 modification to those engines with a compliance 
time different from the compliance time for the Arriel 2B and 2B1 
engines.

Costs of Compliance

    Based on the service information, we estimate that this proposed AD 
would affect about 542 products of U.S. registry. We also estimate that 
it would take about 60 work-hours per product to comply with this AD. 
The average labor rate is $85 per work-hour. Required parts would cost 
about $3,900 per product. Based on these figures, we estimate the cost 
of the AD on U.S. operators to be $4,878,000.

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 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, Incorporation by 
reference, 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) 2011-13-05, Amendment 39-16728 (76 FR 40222, July 8, 2011), and 
adding the following new AD:

Turbomeca S.A.: Docket No. FAA-2011-0115; Directorate Identifier 
2010-NE-40-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by July 31, 
2012.

(b) Affected ADs

    This AD supersedes AD 2011-13-05, Amendment 39-16728 (76 FR 
40222, July 8, 2011).

(c) Applicability

    This AD applies to Turbomeca S.A. Arriel 2B, 2B1, and 2S2 
turboshaft engines not modified by TU166 modification.

(d) Unsafe Condition

    This AD was prompted by reports of an accident involving a twin-
engine helicopter powered by two Arriel 2S2 engines. We are issuing 
this AD to prevent rupture of a gas generator (GG) turbine blade, 
which could result in an uncommanded in-flight shutdown and a forced 
landing or accident.

(e) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.
    (1) For Arriel 2B and 2B1 turboshaft engines, accomplish the 
TU166 modification in accordance with the instructions specified 
within Turbomeca Alert Mandatory Service Bulletin (MSB) No. A292 72 
3166 Version B, dated September 20, 2010, when the GG Turbine is 
replaced or when the engine or Module M03 is going through overhaul 
or repair, or within 676 cycles-in-service (CIS) after the effective 
date of this AD, whichever occurs first.
    (2) For Arriel 2S2 turboshaft engines, accomplish the TU166 
modification in accordance with the instructions specified within 
Turbomeca Alert MSB No. A292 72 4166 Version A, dated March 23, 
2012, when the GG Turbine is replaced or when the engine or Module 
M03 is going through overhaul or repair, or within 500 CIS after the 
effective date of this AD, whichever occurs first.

(f) Credit for Previous Actions

    For Arriel 2B and 2B1 turboshaft engines, if before the 
effective date of this AD, you performed the TU166 modification 
using Turbomeca Alert MSB No. A292 72 3166 Version A, dated August 
17, 2010, you met the requirements of this AD.

[[Page 32439]]

(g) Alternative Methods of Compliance (AMOCs)

    The Manager, Engine Certification Office, may approve AMOCs for 
this AD. Use the procedures found in 14 CFR 39.19 to make your 
request.

(h) Related Information

    (1) For more information about this AD, 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: 
rose.len@faa.gov.
    (2) European Aviation Safety Agency AD 2012-0054, dated April 2, 
2012, also pertains to this AD.
    (3) For service information identified in this AD, contact 
Turbomeca, 40220 Tarnos, France; phone: 33 (0)5 59 74 40 00; telex: 
570 042; fax: 33 (0)5 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. 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.

    Issued in Burlington, Massachusetts, on May 25, 2012.
Pete A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-13324 Filed 5-31-12; 8:45 am]
BILLING CODE 4910-13-P


