E9-31275. Airworthiness Directives; Rolls-Royce plc 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:

During 2004, an incident was reported involving uncontained multiple intermediate-pressure (IP) turbine blade release on a Trent 700 engine. The blade release was the result of an overspeed of the IP turbine rotor that was initiated by an internal fire in the high-pressure/intermediate-pressure (HP/IP) bearing chamber. Post-incident analysis and investigation has established that blockage of the HP/IP turbine bearing oil vent tube due to carbon deposits was a significant factor in the failure sequence. The Trent 800 has a similar type design standard to that of the Trent 700 and has also been found in service to be susceptible to carbon deposits in the oil vent tube.

We are proposing this AD to prevent internal oil fires due to coking and carbon buildup in the HP/IP turbine bearing oil vent tube that could cause uncontained engine failure and damage to the airplane.

DATES:

We must receive comments on this proposed AD by February 4, 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: [phone].

Contact Rolls-Royce plc, P.O. Box 31, Derby, England; telephone: [phone]; fax: [phone], 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 [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:

James Lawrence, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: [e-mail]; telephone [phone]; fax [phone].

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-2009-1004; Directorate Identifier 2009-NE-36-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, notified us that an unsafe condition may exist on Rolls-Royce plc RB211 Trent 800 series turbofan engines. The MCAI states:

During 2004, an incident was reported involving uncontained multiple IP turbine blade release on a Trent 700 engine. The blade release was the result of an overspeed of the IP turbine rotor that was initiated by an internal fire in the HP/IP bearing chamber. Post-incident analysis and investigation has established that blockage of the HP/IP turbine bearing oil vent tube due to carbon deposits was a significant factor in the failure sequence. The Trent 800 has a similar type design standard to that of the Trent 700 and has also been found in service to be susceptible to carbon deposits in the oil vent tube.

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

Relevant Service Information

Rolls-Royce plc has issued Alert Service Bulletin (ASB) No. RB.211-72-AE362, Revision 1, dated April 3, 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 (U.K.) and is approved for operation in the United States. Pursuant to our bilateral agreement with the U.K., EASA has notified us of the unsafe condition described in the MCAI. 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. This proposed AD would require inspection of the HP/IP turbine vent tube and bearing chamber during each shop visit of the engine for coking and carbon buildup in the HP/IP turbine bearing oil vent tube.

Costs of Compliance

Based on the service information, we estimate that this proposed AD would affect about 138 RB211 Trent 800 series turbofan engines installed on airplanes 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 $80 per work-hour. Required parts would cost about $2,000 per engine. Based on these figures, we estimate the cost of the proposed AD on U.S. operators to be $287,040.

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:

Rolls-Royce plc: Docket No. FAA-2009-1004; Directorate Identifier 2009-NE-36-AD.

Comments Due Date

(a) We must receive comments by February 4, 2010.

Affected Airworthiness Directives (ADs)

(b) None.

Applicability

(c) This AD applies to Rolls-Royce plc RB211-Trent 875-17, Trent 877-17, Trent 884-17, Trent 884B-17, Trent 892-17, Trent 892B-17, and Trent 895-17 turbofan engines. These engines are installed on, but not limited to, Boeing 777 series airplanes.

Reason

(d) During 2004, an incident was reported involving uncontained multiple intermediate-pressure (IP) turbine blade release on a Trent 700 engine. The blade release was the result of an overspeed of the IP turbine rotor that was initiated by an internal fire in the high-pressure/intermediate-pressure (HP/IP) bearing chamber. Post-incident analysis and investigation has established that blockage of the HP/IP turbine bearing oil vent tube due to carbon deposits was a significant factor in the failure sequence. The Trent 800 has a similar type design standard to that of the Trent 700 and has also been found in service to be susceptible to carbon deposits in the oil vent tube.

This 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. We are issuing this AD to prevent internal oil fires due to coking and carbon buildup in the HP/IP turbine bearing oil vent tube that could cause uncontained engine failure and damage to the airplane.

Actions and Compliance

(e) Unless already done, do the following actions.

(1) At the next engine shop visit after the effective date of this AD and thereafter at each engine shop visit, using the Accomplishment Instructions of Rolls-Royce plc Alert Service Bulletin No. RB.211-72-AE362, Revision 1, dated April 3, 2009:

(i) Inspect the HP/IP turbine bearing internal and external oil vent tubes and bearing chamber for carbon buildup.

(ii) Clean and flush the tubes and bearing chamber as required.

(iii) Reject any oil vent tubes that do not meet inspection requirements after cleaning.

(2) This AD does not require reporting of inspection results, as does paragraphs 3.B.(4)(g) and 3.C.(9) of Rolls-Royce plc Alert Service Bulletin No. RB.211-72-AE362, Revision 1, dated April 3, 2009.

FAA AD Differences

(f) None.

Alternative Methods of Compliance (AMOCs)

(g) The Manager, Engine Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19.

Related Information

(h) Refer to MCAI European Aviation Safety Agency AD 2009-0071 (corrected April 14, 2009), and Rolls-Royce plc Alert Service Bulletin No. RB.211-72-AE362, Revision 1, dated April 3, 2009, for related information. Contact Rolls-Royce plc, P.O. Box 31, Derby, England; telephone: [phone]; fax: [phone], for a copy of this service information.

(i) Contact James Lawrence, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: [e-mail]; telephone [phone]; fax [phone], for more information about this AD.

Issued in Burlington, Massachusetts, on December 29, 2009.

Francis A. Favara,

Manager, Engine and Propeller Directorate, Aircraft Certification Service.