Airworthiness Directives; Rolls-Royce plc (RR) RB211-Trent 800 Series Turbofan Engines

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Revision of the Critical Part lives has been necessary due to actual operational flight profiles not conforming to those assumed at entry into service and is associated with a revised Flight Profile Monitoring methodology (originally based on engine thrust rating but now based on operating shaft speeds) introduced by Rolls-Royce.

The new Flight Profile Monitoring methodology allows for seven new profiles replacing the previous three. Six of these profiles, A to F, are intended to cover the requirements of most operators. The Declared Life (in Standard Duty Cycles) is published for each part and life usage may be accounted by factoring the number of flights flown. The factor to be used is defined according to the Flight Profile which is applicable to the fleet.

The seventh profile, called “Heavy”, will be applicable to fleets operating outside profiles A to F. A separate Declared Life (in Flight Cycles) is published for each part and life usage is accounted without factoring.

We are proposing this AD to prevent failure of critical rotating parts from exceeding the new, lower life limits, which could result in uncontained failure of the engine and damage to the airplane.

DATES:

We must receive comments on this proposed AD by September 17, 2010.

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: (202) 493-2251.

Contact Rolls-Royce plc, P.O. Box 31, Derby, DE24 8BJ, United Kingdom: Telephone 44 (0) 1332 242424; fax 44 (0) 1332 249936, for the service information identified in this proposed AD.

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 (telephone (800) 647-5527) 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:

James Lawrence, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: james.lawrence@faa.gov; telephone (781) 238-7176; fax (781) 238-7199.

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-2010-0755; Directorate Identifier 2010-NE-12-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 2007-0003R1, dated January 15, 2009 (referred to after this as “the MCAI”), to correct an unsafe condition for the specified products. The MCAI states:

The MCAI describes the unsafe condition as:

Revision of the Critical Part lives has been necessary due to actual operational flight profiles not conforming to those assumed at entry into service and is associated with a revised Flight Profile Monitoring methodology (originally based on engine thrust rating but now based on operating shaft speeds) introduced by Rolls-Royce.

The new Flight Profile Monitoring methodology allows for seven new profiles replacing the previous three. Six of these profiles, A to F, are intended to cover the requirements of most operators. The Declared Life (in Standard Duty Cycles) is published for each part and life usage may be accounted by factoring the number of flights flown. The factor to be used is defined according to the Flight Profile which is applicable to the fleet.

The seventh profile, called “Heavy”, will be applicable to fleets operating outside profiles A to F. A separate Declared Life (in Flight Cycles) is published for each part and life usage is accounted without factoring.

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

Relevant Service Information

Rolls-Royce plc has issued RB211 Trent 800 Series Propulsion System Non-Modification Service Bulletin Alert RB.211-72-AE935, Revision 7, dated January 19, 2009. The actions described in this service information are intended to correct the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of This Proposed AD

This product has been approved by the aviation authority of the United Kingdom, and is approved for operation in the United States. Pursuant to our bilateral agreement with the United Kingdom, they have 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.

Differences Between This AD and the MCAI or Service Information

The MCAI requires incorporating the revised Trent 800 life limits no later than January 31, 2007. This proposed AD would require incorporating the revised Trent 800 life limits within 30 days after the effective date of this proposed AD.

Costs of Compliance

Based on the service information, we estimate that this proposed AD would affect about 16 products of U.S. registry. The average labor rate is $85 per work-hour; there is no labor cost because disks are replaced at scheduled maintenance intervals. Prorated cost of parts would cost about $45,000 per product. Based on these figures, we estimate the cost of the proposed AD on U.S. operators to be $720,000.

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
• 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.