DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2009-0889; Product Identifier 2009-NE-35-AD]
RIN 2120-AA64

Airworthiness Directives; Safran Helicopter Engines, S.A.,
Turboshaft Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to supersede airworthiness directive (AD) 2012-03-
11 that applies to all Safran Helicopter Engines, S.A., Arriel 2B and
2B1 turboshaft engines. AD 2012-03-11 requires checking the
transmissible torque between the low-pressure (LP) pump impeller and
the high-pressure (HP) pump shaft on the HP/LP pump and metering valve
assembly, hereafter referred to as the hydro-mechanical metering unit
(HMU). Since we issued AD 2012-03-11, the manufacturer determined that
incorporating Modification TU 178 is a more effective method to reduce
the risk of uncoupling between the LP fuel pump impeller and the HP
fuel pump shaft than the prior Modification TU 147. This proposed AD
would require inspection and possible replacement of the HMU. We are
proposing this AD to address the unsafe condition on these products.

DATES: We must receive comments on this proposed AD by November 20, 2017.

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 NPRM, contact Safran
Helicopter Engines, S.A., 40220 Tarnos, France; phone: (33) 05 59 74 40
00; fax: (33) 05 59 74 45 15. You may view this service information at
the FAA, Engine and Propeller Standards Branch, 1200 District Avenue,
Burlington, MA. For information on the availability of this material at
the FAA, call 781-238-7125. It is also available on the Internet at
http://www.regulations.gov by searching for and locating Docket No.
FAA-2009-0889.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.
gov by searching for and locating Docket No. FAA-2009-0889;
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 mandatory continuing airworthiness
information, regulatory evaluation, any comments received, and other
information. The 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: Robert Green, Aerospace Engineer, ECO
Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-
238-7754; fax: 781-238-7199; email: robert.green@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under the ADDRESSES section. Include "Docket No. FAA-2009-0889;
Product Identifier 2009-NE-35-AD" at the beginning of your comments.
We specifically invite comments on the overall regulatory, economic,
environmental, and energy aspects of this NPRM. We will consider all
comments received by the closing date and may amend this NPRM 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 NPRM.

Discussion

We issued AD 2012-03-11, Amendment 39-16953 (77 FR 8092, February
14, 2012), "AD 2012-03-11," for all Turbomeca S.A. Arriel 2B and 2B1
turboshaft engines. AD 2012-03-11 requires checking the transmissible
torque between the LP pump impeller and the HP pump shaft on the pre-
and post-Modification TU 147 HMUs. AD 2012-03-11 resulted from
instances of uncoupling between the LP fuel pump impeller and the HP
fuel pump shaft. We issued AD 2012-03-11 to prevent an uncommanded in-
flight shutdown, which can result in a forced autorotation landing or
accident.

Actions Since AD 2012-03-11 Was Issued

Since we issued AD 2012-03-11, the manufacturer determined that
modification of an engine to incorporate Modification TU 178 is a more
effective method to reduce the risk of uncoupling between the LP fuel
pump impeller and the HP fuel pump shaft than the prior Modification TU
147. Also since we issued AD 2012-03-11, the European Aviation Safety
Agency (EASA) has issued AD 2017-0102, dated June 13, 2017, which
requires inspection and possible replacement of the HMU.

Related Service Information Under 1 CFR Part 51

Turbomeca, S.A., has issued Alert Mandatory Service Bulletin (MSB)
A292 73 2830, Version B, dated July 10, 2009, and Alert MSB A292 73
2836, Version A, dated August 17, 2010. Turbomeca Alert MSB A292 73
2830, Version B, is used to do the inspection for pre-Modification TU
147 HMUs. Turbomeca Alert MSB A292 73 2836, Version A, is used to do
the inspection for HMUs that have incorporated Modification TU 147.
This service information is reasonably available because the interested
parties have access to it through their normal course of business or by
the means identified in the ADDRESSES section.

Other Related Service Information

Safran Helicopter Engines has issued MSB 292 73 2178, Version B,
dated March 23, 2017, introducing an HMU with a reinforced drive link
between the LP impeller and fuel pump drive shaft (Modification TU
178). Safran Helicopter Engines has also issued MSB A292 73 2830,
Version C; and A292 73 2836, Version B, both dated April 5, 2017, which
exempt HMUs incorporating Modification TU 178 from the inspections
previously recommended by Turbomeca.

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 inspection and, depending on the
results of the inspection, possible replacement of the HMU. This
proposed AD would further require replacement of pre-Modification TU
178 HMUs with an HMU incorporating Modification TU 178 within 2,200
engine flight hours or 72 months, whichever occurs later, after the
effective date of this AD.

Costs of Compliance

We estimate that this proposed AD affects 417 engines installed on
helicopters of U.S. registry.

We estimate the following costs to comply with this proposed AD:

Estimated Costs

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.

This AD is issued in accordance with authority delegated by the
Executive Director, Aircraft Certification Service, as authorized by
FAA Order 8000.51C. In accordance with that order, issuance of ADs is
normally a function of the Compliance and Airworthiness Division, but
during this transition period, the Executive Director has delegated the
authority to issue ADs applicable to engines, propellers, and
associated appliances to the Manager, Engine and Propeller Standards
Branch, Policy and Innovation Division.

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 to the extent
that it justifies making a regulatory distinction, 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)
2012-03-11, Amendment 39-16953 (77 FR 8092, February 14, 2012), and
adding the following new AD: