AD 2013-05-01

We are superseding an existing airworthiness directive (AD) for all Turbomeca S.A. Makila 1A2 turboshaft engines. That AD currently requires replacement of certain serial number (S/N) N2 sensor harnesses. This AD requires replacement of the same S/N harnesses, and requires replacement of additional S/N N2 sensor harnesses. This AD was prompted by corrosion detected in affected N2 sensor harnesses. We are issuing this AD to prevent inadvertent activation of the 65% N1 back up mode, resulting in N2 speed fluctuation, significant power loss, and emergency landing of the helicopter.

Final rule; request for comments.

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends part 39 of the Federal Aviation Regulations (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 airworthiness directive (AD) 2011-24-08, Amendment 39-16872 (76 FR 72091, November 22, 2011) and adding the following new AD:

2013-05-01 Turbomeca S.A.: Amendment 39-17373; Docket No. FAA-2011- 1037; Directorate Identifier 2011-NE-30-AD.

(a) Effective Date

This AD is effective March 21, 2013.

(b) Affected ADs

This AD supersedes AD 2011-24-08, Amendment 39-16872 (76 FR 72091, November 22, 2011).

(c) Applicability

This AD applies to all Turbomeca S.A. Makila 1A2 turboshaft engines with an N2 sensor harness, part number (P/N) 0 301 52 001 0, installed, with:
(1) A serial number (S/N) 242 through 339, inclusive, or
(2) A S/N 691 through 705, inclusive, 707 through 728, inclusive, or 813 through 844, inclusive.

(d) Unsafe Condition

This AD was prompted by corrosion detected in affected N2 sensor harnesses. We are issuing this AD to prevent inadvertent activation of the 65% N1 back up mode, resulting in N2 speed fluctuation, significant power loss, and emergency landing of the helicopter.

(e) Compliance

Comply with this AD within the compliance times specified, unless already done.
(1) For engines listed in paragraph (c)(1) of this AD with an affected N2 sensor harness installed on both engines of the helicopter, do the following:
(i) Replace one N2 sensor harness with an N2 sensor harness that is eligible for installation within 10 flight hours (FHs) after December 7, 2011, or before the next flight after the effective date of this AD, whichever occurs later, and
(ii)Replace the second N2 sensor harness with an N2 sensor harness that is eligible for installation within 50 FHs after December 7, 2011, or before the next flight after the effective date of this AD, whichever occurs later.
(2) For engines listed in paragraph (c)(1) of this AD with an affected N2 sensor harness installed on only one engine of the helicopter, replace the affected N2 sensor harness with an N2 sensor harness that is eligible for installation within 50 FHs after December 7, 2011, or before the next flight after the effective date of this AD, whichever occurs later.

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(3) For engines listed in paragraph (c)(2) of this AD with an affected N2 sensor harness installed on both engines of the helicopter, do the following:
(i) Replace one N2 sensor harness with an N2 sensor harness that is eligible for installation within 10 FHs after the effective date of this AD, and
(ii) Replace the second N2 sensor harness with an N2 sensor harness that is eligible for installation within 50 FHs after the effective date of this AD.
(4) For engines listed in paragraph (c)(2) of this AD with an affected N2 sensor harness installed on only one engine of the helicopter, replace the affected N2 sensor harness with an N2 sensor harness that is eligible for installation within 50 FHs after the effective date of this AD.
(5) If an affected N2 sensor harness is installed on both engines of the helicopter, one from paragraph (c)(1) of this AD and one from paragraph (c)(2) of this AD, then within 10 FHs after December 7, 2011, or before the next flight after the effective date of this AD, whichever occurs later, replace the N2 sensor harness from paragraph (c)(1) with an N2 sensor harness that is eligible for installation and within 50 FHs after the effective date of this AD, replace the harness from paragraph (c)(2) with an N2 sensor harness that is eligible for installation.

(f) Installation Prohibition

(1) After the effective date ofthis AD, do not install on any engine any N2 sensor harness, P/N 0 301 52 001 0, with a S/N listed in paragraphs (c)(1) and (c)(2) of this AD, unless the N2 sensor harness has ``SB 0815'' marked on its identification plate.
(2) After the effective date of this AD, do not install in a helicopter, any engine with an N2 sensor harness, P/N 0 301 52 001 0, installed, with a S/N listed in paragraphs (c)(1) and (c)(2) of this AD, unless the N2 sensor harness has ``SB 0815'' marked on its identification plate.

(g) Alternative Methods of Compliance (AMOCs)

The Manager, Engine Certification Office, FAA, may approve AMOCs for this AD. Use the procedures 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, 12 New England Executive Park, Burlington, MA 01803; phone: 781-2328-7772; fax: 781-238-7199; email: rose.len@faa.gov.
(2) Turbomeca S.A. Alert Mandatory Service Bulletin (MSB) No. A298 77 0821, Version A, dated October 9, 2012, and MSB No. 298 77 0817, Version B, dated August 23, 2011, pertain to the subject of 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; Web site: http://www.turbomeca-support.com. You may view this service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803. For information on the availability of this material at the FAA, call 781-238-7125.

(i) Material Incorporated by Reference

None.

Discussion

On November 9, 2011, we issued AD 2011-24-08, Amendment 39-16872 (76 FR 72091, November 22, 2011), for all Turbomeca S.A. Makila 1A2 turboshaft engines with certain part number (P/N) N2 sensor harnesses installed. That AD requires replacement of certain S/Ns of the affected N2 sensor harnesses, on the two engines of the helicopter. That AD resulted from mandatory continuing airworthiness information 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 inadvertent activation of the 65% N1 backup control mode, as a result of defective N2 sensor harness crimps, which could result in engine power loss and emergency landing of the helicopter.

Actions Since AD Was Issued

Since we issued AD 2011-24-08 (76 FR 72091, November 22, 2011), Turbomeca S.A. has determined through investigation that additional S/ Ns of the N2 sensor harness, P/N 0 301 52 001 0, are affected and require replacement.

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The investigation detected corrosion in the harness inside the cable sheath, at the splices with the sensor coils. This corrosion is attributed to a manufacturing error. We are issuing this AD to include additional S/Ns of the N2 sensor harness.

Relevant Service Information

We reviewed Turbomeca S.A. Alert Mandatory Service Bulletin (MSB) No. A298 77 0821, Version A, dated October 9, 2012, and MSB No. 298 77 0817, Version B, dated August 23, 2011. This service information describes procedures for checking and replacing affected N2 sensor harnesses.

FAA's Determination

We are issuing this AD because we evaluated all the relevant information and determined the unsafe condition exists and is likely to exist or develop on other products of the same type design.

AD Requirements

This AD requires replacement of certain S/Ns of N2 sensor harnesses, P/N 0 301 52 001 0.

FAA's Justification and Determination of the Effective Date

There are no U.S. operators for this product. Therefore, we find that notice and opportunity for prior public comment are unnecessary and that good cause exists for making this amendment effective in less than 30 days.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety, and we did not provide you with notice and an opportunity to provide your comments before it becomes effective. However, we invite you to send any written data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include ``Docket Number FAA-2011-1037; Directorate Identifier 2011-NE-30-AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this 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 AD.

Costs of Compliance

There are no engines installed on helicopters of U.S. registry that will be affected by this AD. Therefore, we estimate the cost of this AD on 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

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 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 affect intrastate aviation in Alaska to the extent that it justifies making a regulatory distinction, and
(4) Willnot 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.