03-18078. Airworthiness Directives; Rolls-Royce plc RB211-524G2, -524G2-T, -524G3, -524G3-T, -524H, -524H-T, -524H2, and -524H2-T Series, and Models RB211 Trent 768-60, 772-60, and 772B-60 Turbofan Engines

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for Rolls-Royce plc (RR) RB211-524G2, -524G2-T, -524G3, -524G3-T, -524H, -524H-T, -524H2, and -524H2-T series, and models RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines with high pressure compressor (HPC) rotor stage 1 through stage 6 drums, part numbers (P/Ns) FK25502 and FW20195 installed. This AD is prompted by reports of cracks found in loading slots of HPC rotor stage 1 through stage 6 drums. We are issuing this AD to prevent crack initiation and propagation leading to uncontained failure of the HPC rotor stage 1 through stage 6 drum, and damage to the airplane.

DATES:

Effective August 1, 2003.

We must receive any comments on this AD by September 15, 2003.

ADDRESSES:

Use one of the following addresses to submit comments on this AD:

• By mail: The Federal Aviation Administration (FAA), New England Region, Office of the Regional Counsel, Attention: Rules Docket No. 2003-NE-20-AD, 12 New England Executive Park, Burlington, MA 01803-5299.
• By fax: [phone].
• By e-mail: [e-mail]

You may examine the AD docket, by appointment, at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA.

FOR FURTHER INFORMATION CONTACT:

Antonio Cancelliere, 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 Civil Aviation Authority (CAA), which is the airworthiness authority for the U.K., recently notified the FAA that an unsafe condition may exist on RR RB211-524G2, -524G2-T, -524G3, -524G3-T, -524H, -524H-T, -524H2, and -524H2-T series, and models RB211 Trent 768-60, -772-60, and 772B-60 turbofan engines with HPC stage 1 through stage 6 drums, P/Ns FK25502 and FW20195 installed. The CAA advises that reports have been received of a number of RR Trent 700 series HPC rotor stage 1 through stage 6 drums found with cracks in the blade loading slots. The RB211-524G2, -524G2-T, -524G3, -524G3-T, -524H, -524H-T, -524H2, and -524H2-T series turbofan engines use an identical HPC rotor stage 1 through stage 6 drum. To date, one drum has been found with cracks. The manufacturer's investigation has revealed that the mechanism inducing the cracking is a function of engine operating time and temperature, and is initiating cracks in the area of peak stress location. This AD requires removal from service of affected HPC rotor stage 1 through stage 6 drums at a newly established reduced cyclic life limit. We are requiring certain actions in this AD to prevent crack initiation and propagation leading to uncontained failure of the HPC rotor stage 1 through stage 6 drum, and damage to the airplane.

FAA's Determination and Requirements of This AD

Although none of these affected engine models are used on any airplanes that are registered in the United States, the possibility exists that the engine models could be used on airplanes that are registered in the United States in the future. Since an unsafe condition has been identified that is likely to exist or develop on other Rolls-Royce plc RB211-524G2, -524G2-T, -524G3, -524G3-T, -524H, -524H-T, -524H2, and -524H2-T series, and models RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines of this same type design, we are issuing this AD to prevent crack initiation and propagation leading to uncontained failure of the HPC rotor stage 1 through stage 6 drum, and damage to the airplane. This AD requires removal of HPC rotor stage 1 through stage 6 drums, P/Ns FK25502 and FW20195, at a newly established reduced cyclic life limit of 4,200 cycles-since-new.

Bilateral Airworthiness Agreement

This engine model is manufactured in the U.K., and is type certificated for operation in the United States under the provisions of § 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. In keeping with this bilateral airworthiness agreement, the CAA has kept the FAA informed of the situation described above. We have examined the findings of the CAA, 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 of the Effective Date

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

Changes to 14 CFR Part 39—Effect on the AD

On July 10, 2002, we issued a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs our AD system. This regulation now includes material that relates to special flight permits, alternative methods of compliance, and altered products. This material previously was included in each individual AD. Since this material is included in 14 CFR part 39, we will not include it in future AD actions.

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 submit any written relevant data, views, or arguments regarding this AD. Send your comments to an address listed under ADDRESSES. Include “AD Docket No. 2003-NE-20-AD” in the subject line of your comments. If you want us to acknowledge receipt of your mailed comments, send us a self-addressed, stamped postcard with the docket number written on it; we will date-stamp your postcard and mail it back to you. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify it. If a person contacts us through a nonwritten communication, and that contact relates to a substantive part of this AD, we will summarize the contact and place the summary in the docket. We will consider all comments received by the closing date and may amend the AD in light of those comments.

We are reviewing the writing style we currently use in regulatory documents. We are interested in your comments on whether the style of this document is clear, and your suggestions to improve the clarity of our communications with you. You may get more information about plain language at http://www.plainlanguage.gov.

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. 2003-NE-20-AD” in your request.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

Adoption of the Amendment

Accordingly, 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:

2003-14-23 Rolls-Royce plc: Amendment 39-13242. Docket No. 2003-NE-20-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective August 1, 2003.

Affected ADs

(b) None.

Applicability:

(c) This AD applies to Rolls-Royce plc RB211-524G2, -524G2-T, -524G3, -524G3-T, -524H, -524H-T, -524H2, and “524H2-T series, and models RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines with high pressure compressor (HPC) rotor stage 1 through stage 6 drums, part numbers (P/Ns) FK25502 and FW20195 installed. These engines are installed on, but not limited to, Airbus A330 series, Boeing 747-400 series, and 767-300 series airplanes.

Unsafe Condition

(d) This AD is prompted by reports of cracks found in loading slots of HPC rotor stage 1 through stage 6 drums. We are issuing this AD to prevent crack initiation and propagation leading to uncontained failure of the HPC rotor stage 1 through stage 6 drum, and damage to the airplane.

Compliance:

(e) If you have not already performed the actions required sby this AD, you must perform the actions within the compliance cycles specified in this AD.

Required Actions

(f) Remove HPC rotor stage 1 through stage 6 drums, P/Ns FK25502 and FW20195, from service at or before accumulating 4,200 cycles-since-new (CSN).

(g) After the effective date of this AD, do not install any HPC rotor stage 1 through stage 6 drum, P/N FK25502 or FW20195, that exceeds 4,200 CSN.

Alternative Methods of Compliance (AMOCs)

(h) You must request AMOCs as specified in 14 CFR part 39.19. All AMOCs must be approved by the Manager, Engine Certification Office, FAA.

Material Incorporated by Reference

(i) None.

Related Information

(j) CAA airworthiness directive 004-02-2003, dated April 2003, also addresses the subject of this AD.

Issued in Burlington, Massachusetts, on July 11, 2003.

Francis A. Favara,

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