2012-3860. Airworthiness Directives; Turbomeca S.A. Turboshaft Engines

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for Turbomeca S.A. Arriel 2C1, 2C2, and 2S2 turboshaft engines. This proposed AD was prompted by a report of a helicopter experiencing a digital engine control unit (DECU) malfunction during flight. We are proposing this AD to prevent loss of automatic control on one or both engines installed on the same helicopter, which could result in an uncommanded in-flight engine shutdown, forced autorotation landing, or accident.

DATES:

We must receive comments on this proposed AD by April 23, 2012.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
• Mail: Docket Management Facility, U.S. Department of Transportation, 1200 New Jersey Avenue SE., West Building Ground Floor, Room W12-140, Washington, DC 20590-0001.
• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
• Fax: [phone].

For service information identified in this proposed AD, contact Turbomeca, 40220 Tarnos, France; phone: [phone]; fax: [phone]. 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 Operations office 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 Operations office (phone: [phone]) is the same as the Mail address provided 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: [phone]; fax: [phone]; email: [e-mail].

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-2012-0057; Directorate Identifier 2012-NE-04-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 based on 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 with FAA personnel concerning this proposed AD. Using the search function of the Web site, anyone can find and read the comments in any of our dockets, including, if provided, the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78).

Discussion

The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community, has issued EASA Airworthiness Directive 2011-0249, dated December 22, 2011 (referred to after this as “the MCAI”), to correct an unsafe condition for the specified products. The MCAI states:

An incident has been reported of a helicopter which experienced a Digital Engine Control Unit (DECU) malfunction in flight from one of its Arriel 2C1 engines. The indicating system of the helicopter displayed a “FADEC FAIL” message, with a concurrent loss of automatic control of the engine. The mission was aborted and the helicopter returned to its base without any further incident.

The subsequent technical investigations carried out by Turbomeca revealed that a Digital Engine Control Unit (DECU) assembly non-conformity was at the origin of this event. Further investigations performed with the supplier of the DECU led to the conclusion that only a limited number of DECU are potentially affected by the non-conformity.

You may obtain further information by examining the MCAI in the AD docket.

Relevant Service Information

Turbomeca S.A. has issued Alert Mandatory Service Bulletin No. A292 73 2845, Version A, dated December 19, 2011. The actions described in this service information are intended to correct the unsafe condition identified in the MCAI.

FAA's Determination of This Proposed AD

This product has been approved by the aviation authority of France, and is approved for operation in the United States. Pursuant to our bilateral agreement with EASA, EASA has notified us of the unsafe condition described in the MCAI and service information referenced above. We are proposing this AD because we evaluated all information provided by EASA and determined the unsafe condition exists and is likely to exist or develop on other products of the same type design.

Costs of Compliance

Based on the service information, we estimate that this proposed AD would affect about two engines installed on helicopters of U.S. registry. We also estimate that it would take about one work-hour per engine to comply with this proposed AD. The average labor rate is $85 per work-hour. Required parts would cost about $12,551 per engine. Based on these figures, we estimate the cost of the proposed AD on U.S. operators to be $25,272. 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 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 this 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); 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 proposed AD and placed it in the AD docket.

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.

§ 39.13

[Amended]

2. The FAA amends § 39.13 by adding the following new AD:

Turbomeca S.A.: Docket No. FAA-2012-0057; Directorate Identifier 2012-NE-04-AD.

(a) Comments Due Date

We must receive comments by April 23, 2012.

(b) Affected Airworthiness Directives (ADs)

None.

(c) Applicability

This AD applies to Turbomeca S.A. Arriel 2C1, 2C2, and 2S2 turboshaft engines with any of the digital engine control units (DECUs) listed in Table 1 of this AD installed.

Table 1—Serial Numbers of Affected DECU

529	558	560	655
696	869	878	939
983	1039	1050	1052
1150	1195	1208	1236
1302	1304	1329	1330
1350	1384	1408	1412
1416	1429	1430	1440
1464	1468	1472	1499
1508	1528	1557	1558
1560	1567	1578	1615
1616	1656	1689	N/A

(d) Reason

This AD was prompted by a report of a helicopter experiencing a DECU malfunction during flight. We are issuing this AD to prevent loss of automatic control on one or both engines installed on the same helicopter, which could result in an uncommanded in-flight engine shutdown, forced autorotation landing, or accident.

(e) Actions and Compliance

Unless already done, do the following actions.

(1) For any helicopter fitted with two DECUs listed in Table 1 of this AD:

(i) Within 50 engine hours after the effective date of this AD, replace one of the two DECUs with a DECU that is not listed in Table 1 of this AD.

(ii) Within 1,000 engine hours or 12 months after the effective date of this AD, whichever occurs first, replace the other DECU with a DECU that is not listed in Table 1 of this AD.

(2) For any helicopter fitted with one DECU listed in Table 1 of this AD, within 1,000 engine hours or 12 months after the effective date of this AD, whichever occurs first, replace the DECU with a DECU that is not listed in Table 1 of this AD.

(f) Installation Prohibition

From the effective date of this AD, do not install a DECU listed in Table 1 of this AD onto any engine, and do not install any engine having a DECU listed in Table 1 of this AD, onto a helicopter.

(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: [phone]; fax: [phone]; email: [e-mail].

(2) Refer to European Aviation Safety Agency AD 2011-0249, dated December 22, 2011, and Turbomeca Alert Mandatory Service Bulletin No. A292 73 2845, Version A, dated December 19, 2011, for related information.

(3) For service information identified in this AD, contact Turbomeca, 40220 Tarnos, France; phone: [phone]; fax: [phone]. 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 February 10, 2012.

Peter A. White,

Manager, Engine & Propeller Directorate, Aircraft Certification Service.