05-18322. Airworthiness Directives; Turbomeca Arrius 2 F Turboshaft Engines

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Final rule; request for comments.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for Turbomeca Arrius 2 F turboshaft engines. This AD requires removing from service certain serial number (SN) fuel control units (FCUs) or replacing the constant delta pressure diaphragm in those FCUs. This AD results from a report of an accident in July 2005 involving a Eurocopter EC120B helicopter. We are issuing this AD to prevent an uncommanded engine in-flight shutdown on a single-engine helicopter, resulting in a forced autorotation landing or an accident.

DATES:

Effective October 3, 2005. The Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulations as of October 3, 2005.

We must receive any comments on this AD by November 15, 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 20590-0001.
• 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, 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 the FAA that an unsafe condition may exist on Turbomeca Arrius 2 F turboshaft engines. The DGAC advises that a Eurocopter EC120B helicopter powered by an Arrius 2 F turboshaft engine experienced an uncommanded in-flight engine shutdown. An increase in fuel flow led to an increase in gas generator and power turbine speeds. Turbine blades separated from the disk due to the overspeed. Turbomeca determined that the fuel flow increase was caused by an improperly assembled and subsequent failure of the constant delta pressure (delta P) diaphragm in the FCU. Only certain types of constant delta P diaphragms have been identified as being capable of being improperly assembled. Engine serial numbers that may have this type of constant delta P diaphragm are listed in Turbomeca Alert Mandatory Service Bulletin (MSB) No. A319 73 4825, dated August 3, 2005. The manufacturer is making spare FCUs available as fast as possible and has established a rotable pool of spares. After we reviewed the Turbomeca SB, we concluded that using the Turbomeca rotable pool of spares as soon as practicable effectively manages the risk of another failure of the uninspected engine population. To this end, we are requiring that FCUs identified in the Turbomeca SB be replaced as soon as practicable but not to exceed February 28, 2006. Because the practicable compliance time may be quite short for some operators and the rotable pool requires consistent participation, we are issuing this AD as final rule; request for comments.

Relevant Service Information

We have reviewed and approved the technical contents of Turbomeca Alert MSB No. A319 73 4825, dated August 3, 2005. That MSB lists the affected FCUs by SN and describes procedures for removing affected FCUs from service or replacing constant delta P diaphragms in those FCUs. The DGAC classified this service bulletin as mandatory and issued AD No. F-2005-143, dated August 17, 2005, and AD No. F-2005-143 R1, dated August 31, 2005, in order to ensure the airworthiness of these Arrius 2 F turboshaft engines in France.

Bilateral Airworthiness Agreement

This engine model 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 2 F turboshaft engines of the same type design. We are issuing this AD to prevent an uncommanded engine in-flight shutdown on a single-engine helicopter, resulting in a forced autorotation landing or an accident. This AD requires removing from service certain SN FCUs or replacing the constant delta P diaphragm in those FCUs. 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-2005-22430; Directorate Identifier 2005-NE-34-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 Docket Management Facility 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.

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:

2005-19-10 Turbomeca: Amendment 39-14275. Docket No. FAA-2005-22430; Directorate Identifier 2005-NE-34-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective October 3, 2005.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Turbomeca Arrius 2 F turboshaft engines with the fuel control units listed by serial number (SN) in Turbomeca Alert Mandatory Service Bulletin (MSB) No. A319 73 4825, dated August 3, 2005. These engines are installed on, but not limited to, Eurocopter EC120B helicopters.

Unsafe Condition

(d) This AD results from a report of an accident in July 2005 involving a Eurocopter EC120B helicopter. We are issuing this AD to prevent an uncommanded engine in-flight shutdown on a single-engine helicopter, resulting in a forced autorotation landing or an accident.

Compliance

(e) You are responsible for having the actions required by this AD performed as soon as practicable after the effective date of this AD but no later than February 28, 2006, unless the actions have already been done.

(f) Remove FCUs listed by serial number (SN) in Turbomeca Alert Mandatory Service Bulletin (MSB) No. A319 73 4825, dated August 3, 2005.

(g) Install an FCU not listed in Turbomeca Alert MSB No. A319 73 4825, dated August 3, 2005; or one with a new constant delta pressure diaphragm installed using paragraph 2.B. of Turbomeca Alert MSB No. A319 73 4825, dated August 3, 2005.

Alternative Methods of Compliance

(h) 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

(i) DGAC airworthiness directives No. F-2005-143, dated August 17, 2005, and No. F-2005-143 R1, dated August 31, 2005, also address the subject of this AD.

Material Incorporated by Reference

(j) You must use Turbomeca Alert Mandatory Service Bulletin (MSB) No. A319 73 4825, dated August 3, 2005, to perform the actions 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, 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 20590-0001, 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/​cfr/​ibr-locations.html.

Issued in Burlington, Massachusetts, on September 9, 2005.

Jay J. Pardee,

Manager, Engine and Propeller Directorate, Aircraft Certification Service.