E6-18702. Airworthiness Directives; Rolls-Royce plc Trent 768-60, Trent 772-60, and Trent 772B-60 Turbofan 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 Rolls-Royce plc Trent 768-60, Trent 772-60, and Trent 772B-60 turbofan engines. This AD requires removing from service certain sets of fan blade annulus fillers at a new life limit. This AD results from six reports of fan annulus filler release into the engine. We are issuing this AD to prevent a dual-engine shutdown on twin-engine airplanes.

DATES:

Effective November 22, 2006.

We must receive any comments on this AD by January 8, 2007.

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.

FOR FURTHER INFORMATION CONTACT:

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

SUPPLEMENTARY INFORMATION:

The European Aviation Safety Agency (EASA), which is the airworthiness authority for the European community, recently notified us that an unsafe condition may exist on Rolls-Royce plc Trent 768-60, Trent 772-60, and Trent 772B-60 turbofan engines. EASA advises that six occurrences of the release of a fan annulus filler into the engine have occurred in 2005. Because of the number of events, there is a risk of a dual-engine shutdown on twin-engine airplanes.

Bilateral Airworthiness Agreement

These Rolls-Royce plc Trent 768-60, Trent 772-60, and Trent 772B-60 turbofan engines are manufactured in the United Kingdom. They are 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, EASA kept the FAA informed of the situation described above. We have examined the findings of EASA, 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

Although no airplanes that are registered in the United States use these engines, the possibility exists that the engines could be used on airplanes that are registered in the United States in the future. The unsafe condition described previously is likely to exist or develop on other Rolls-Royce plc Trent 768-60, Trent 772-60, and Trent 772B-60 turbofan engines of the same type design. We are issuing this AD to prevent a dual-engine shutdown on twin-engine airplanes. This AD requires the following:

• On or before December 31, 2006, if an airplane has fan annulus fillers, part number (P/N) FK21226, installed in both engines or has fan annulus fillers, P/N FK21226, in one engine and P/N FK22974, in the other engine, then the accumulated life of the fan annulus fillers on at least one engine must not exceed 7,500 cycles-in-service (CIS). Replace one of the engines, or one set of fan annulus fillers before further flight to comply with this requirement.
• After December 31, 2006, remove sets of fan annulus fillers, P/N FK21226, before exceeding the life limit of 6,500 CIS.

FAA's Determination of the Effective Date

Since there are currently no domestic operators of this engine model, notice and opportunity for public comment before issuing this AD are unnecessary. A situation exists that allows the immediate adoption of this regulation.

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-2006-25855; Directorate Identifier 2006-NE-29-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. This includes 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 Office 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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• 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:

2006-23-07 Rolls Royce plc: Amendment 39-14819. Docket No. FAA-2006-25855; Directorate Identifier 2006-NE-29-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective November 22, 2006.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Rolls-Royce plc Trent 768-60, Trent 772-60, and Trent 772B-60 turbofan engines. These engines are installed on, but not limited to, Airbus A330 airplanes.

Unsafe Condition

(d) This AD results from six reports of fan annulus filler release into the engine. We are issuing this AD to prevent a dual-engine shutdown on twin-engine airplanes.

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.

Actions to Take on or Before December 31, 2006

(f) On or before December 31, 2006, if an airplane has fan annulus fillers, part number (P/N) FK21226, installed in both engines or has fan annulus fillers, P/N FK21226, in one engine and P/N FK22974, in the other engine, then the accumulated life of the fan annulus fillers on at least one engine must not exceed 7,500 cycles-in-service (CIS). Replace one of the engines, or one set of fan annulus fillers before further flight to comply with this requirement.

Actions to Take After December 31, 2006

(g) After December 31, 2006, remove sets of fan annulus fillers, P/N FK21226, before exceeding the life limit of 6,500 CIS.

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) EASA airworthiness directive No. 2006-0116, dated May 8, 2006, also addresses the subject of this AD.

(j) Rolls-Royce plc Alert Service Bulletin No. RB.211-72-AF109, dated March 28, 2006, pertains to the subject of this AD.

Issued in Burlington, Massachusetts, on October 31, 2006.

Francis A. Favara,

Manager, Engine and Propeller Directorate, Aircraft Certification Service.