05-10295. Airworthiness Directives; Turbomeca S.A. Arrius 1A Turboshaft Engines

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for Turbomeca S.A. Arrius 1A turboshaft engines. This AD requires initial and repetitive testing of the Free Turbine Overspeed Protection System. This AD results from an investigation into the Digital Electronic Control Unit (DECU) that revealed a malfunction of the Free Turbine Overspeed Protection System. This malfunction can exist despite the DECU passing all functional tests specified in the Engine Maintenance Manual. We are issuing this AD to prevent uncontained engine failure if a free turbine overspeed occurs.

DATES:

Effective June 13, 2005. The Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulations as of June 13, 2005.

We must receive any comments on this AD by July 26, 2005.

ADDRESSES:

Use one of the following addresses to comment on this AD:

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
• Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
• Mail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 20590-001.
• Fax: [phone].
• Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Contact Turbomeca S.A., 40220 Tarnos, France; telephone [phone], fax [phone], for the service information identified in this AD.

FOR FURTHER INFORMATION CONTACT:

Christopher Spinney, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

The Direction Generale de L'Aviation Civile (DGAC), which is the airworthiness authority for France, notified us that an unsafe condition might exist on Turbomeca S.A. Arrius 1A turboshaft engines. The DGAC advises that an investigation into the DECU revealed a malfunction of the Free Turbine Overspeed Protection System. This malfunction can exist despite the DECU passing all functional tests specified in the Engine Maintenance Manual. A malfunction of this overspeed system could lead to uncontained engine failure if a free turbine overspeed occurs.

Relevant Service Information

We have reviewed and approved the technical contents of Turbomeca Alert Mandatory Service Bulletin No. A319 77 0804, dated March 24, 2005, that describes procedures for testing the DECU Free Turbine Overspeed Protection System. The DGAC classified this service bulletin as mandatory and issued AD F-2005-063, dated April 27, 2005, and AD UF-2005-063 R1, dated May 4, 2005, in order to ensure the airworthiness of these Arrius 1A engines in France.

Bilateral Airworthiness Agreement

This Turbomeca Arrius 1A engine is manufactured in France and is type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Under this bilateral airworthiness agreement, the DGAC kept the FAA informed of the situation described above. We have examined the findings of the DGAC, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

FAA's Determination and Requirements of This AD

The unsafe condition described previously is likely to exist or develop on other Turbomeca Arrius 1A turboshaft engines of the same type design. This AD requires initial testing of the Free Turbine Overspeed Protection System within 25 flight hours of the effective date of the AD, and repetitive testing at each functional test of the DECU Free Turbine Overspeed Protection System. We are issuing this AD to prevent uncontained engine failure in the event of a free turbine overspeed. You must use the service information described previously to perform the actions required by this AD.

FAA's Determination of the Effective Date

Since an unsafe condition exists that requires the immediate adoption of this AD, we have found that notice and opportunity for public comment before issuing this AD are impracticable, 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 was not preceded by notice and an opportunity for public comment; however, we invite you to send us any written relevant data, views, or arguments regarding this AD. Send your comments to an address listed under ADDRESSES. Include “AD Docket No. FAA-2005-21273; Directorate Identifier 2005-NE-15-AD” in the subject line of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify it.

We will post all comments we receive, without change, to http://dms.dot.gov,, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this AD. Using the search function of the DMS Web site, anyone can find and read the comments in any of our dockets, including 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) or you may visit http://dms.dot.gov.

Examining the AD Docket

You may examine the docket that contains the AD, any comments received, and any final disposition in person at the DMS Docket Offices between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone [phone]) is located on the plaza level of the Department of Transportation Nassif Building at the street address stated in ADDRESSES. Comments will be available in the AD docket shortly after the DMS receives them.

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 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 the 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 summary of the costs to comply with this AD and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include “AD Docket No. 2005-NE-15-AD” in your request.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

Adoption of the Amendment

Under the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (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 airworthiness directive:

2005-11-01 Turbomeca S.A.: Amendment 39-14103. Docket No. FAA-2005-21273; Directorate Identifier 2005-NE-15-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective June 13, 2005.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Turbomeca S.A. Arrius 1A turboshaft engines. These engines are installed on, but not limited to, Eurocopter AS355N Twinstar helicopters.

Unsafe Condition

(d) This AD results from an investigation into the Digital Electronic Control Unit (DECU) that revealed a malfunction of the Free Turbine Overspeed Protection System can exist despite the DECU passing all functional tests specified in the Engine Maintenance Manual. We are issuing this AD to prevent uncontained engine failure in the event of a free turbine overspeed.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done.

Initial Testing

(f) Within 25 flight hours after the effective date of this AD, test the DECU Free Turbine Overspeed Protection System, using paragraph 2.B. of the Instructions to be Incorporated of Turbomeca Alert Mandatory Service Bulletin No. A319 77 0804, dated March 24, 2005.

(g) If the DECU Free Turbine Overspeed Protection System fails the test specified in paragraph (f) of this AD, replace the DECU before further flight.

Repetitive Testing

(h) Repeat the testing specified in paragraph (f) of this AD at each functional test of the DECU Free Turbine Overspeed Protection System. Information on the functional tests of the DECU Free Turbine Overspeed Protection System can be found in the Engine Maintenance Manual, Section 77-30-01. Recommended intervals for the functional test of the Turbine Overspeed Protection System can be found in the Engine Maintenance Manual, Section 05-10-02.

Alternative Methods of Compliance

(i) The Manager, Engine Certification Office, has the authority to approve alternative methods of compliance for this AD if requested using the procedures found in 14 CFR 39.19.

Related Information

(j) DGAC airworthiness directive F-2005-063, dated April 27, 2005, and UF-2005, 063 R1, dated May 4, 2005, also address the subject of this AD.

Material Incorporated by Reference

(k) You must use Turbomeca Alert Mandatory Service Bulletin No. A319 77 0804, dated March 24, 2005, to perform the tests required by this AD. The Director of the Federal Register approved the incorporation by reference of this service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Turbomeca S.A., 40220 Tarnos, France; telephone [phone], fax [phone], for a copy of this service information. You may review copies at the Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 20590-001, on the Internet at http://dms.dot.gov;​; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html.

Issued in Burlington, Massachusetts, on May 17, 2005.

Robert E. Guyotte,

Acting Manager, Engine and Propeller Directorate, Aircraft Certification Service.