Airworthiness Directives; Rolls-Royce plc. RB211 Trent 768-60, Trent 772-60, and Trent 772B-60 Turbofan Engines

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

This amendment adopts a new airworthiness directive (AD) that is applicable to Rolls-Royce plc. (RR) RB211 Trent 768-60, Trent 772-60, and Trent 772B-60 turbofan engines. This action requires initial and repetitive ultrasonic inspections for cracks in fan blade dovetail roots, and if necessary, replacement with serviceable parts. This amendment is prompted by reports of fan blade failures due to dovetail root cracks. The actions specified in this AD are intended to prevent possible multiple fan blade failures, which could result in an uncontained engine failure and damage to the airplane.

DATES:

Effective August 2, 2000. The incorporation by reference of certain publications listed in the rule is approved by the Director of the Federal Register as of August 2, 2000.

Comments for inclusion in the Rules Docket must be received on or before September 1, 2000.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), New England Region, Office of the Regional Counsel, Attention: Rules Docket No. 2000-NE-05-AD, 12 New England Executive Park, Burlington, MA 01803-5299. Comments may also be sent via the Internet using the following address: “9-ad-engineprop@faa.gov.” Comments sent via the Internet must contain the docket number in the subject line.

The service information referenced in this AD may be obtained from Rolls-Royce plc, PO Box 31, Derby, England; telephone: 011-44-1332-249428; fax 011-44-1332-249223. This information may be examined at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:

James Lawrence, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone 781-238-7176; fax 781-238-7199.

SUPPLEMENTARY INFORMATION:

The Civil Aviation Authority (CAA), which is the airworthiness authority for the United Kingdom (U.K.), recently notified the FAA that an unsafe condition may exist on Rolls-Royce plc. (RR) RB211 Trent 768-60, Trent 772-60, and Trent 772B-60 turbofan engines with fan blade part numbers (P/N's) FK22580, FK23411, FK25441, and FK25968 installed. The CAA received a report of multiple fan blade root cracks in a factory engine. A recent inspection of a set of fan blades from a factory fleet leader test engine has identified small cracks in the blade roots on the convex root flank. To date, this is the only engine that has exhibited the blade root cracks. This condition, if not corrected, could result in possible multiple fan blade failures, which could result in an uncontained engine failure and damage to the airplane.

Manufacturer's Service Information

Rolls-Royce plc (RR) has issued service bulletin (SB) No. RB.211-72-C878, Revision 1, dated December 10, 1999, that specifies procedures for ultrasonic inspections for cracks in fan blade dovetail roots. The CAA classified this SB as mandatory and issued airworthiness directive (AD) 003-11-99 in order to assure the airworthiness of these engines in the U.K.

Differences Between This AD and the Manufacturer's Service Information

This AD applies only to those engines with fan blades having four specific part numbers. The manufacturer's service bulletin is not limited in that fashion. The FAA expects that future changes in the design of the affected fan blades will eliminate the need for the required inspections and that those newer fan blades will have different part numbers. The installation of the newer part number will therefore have the effect of removing the engine from the applicability of this AD.

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 section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the CAA has kept the FAA informed of the situation described above. The FAA has 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.

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. Because an unsafe condition has been identified that is likely to exist or develop on other RR RB211 Trent 768-60, Trent 772-60, and Trent 772B-60 series turbofan engines of the same type design, with fan blade P/N's FK22580, FK23411, FK25441, and FK25968 installed, this AD requires:

• Initial ultrasonic inspections within 200 cycles after the effective date of this AD, or within 200 cycles of achieving 2,800 cycles since new, whichever is later; and
• Repetitive ultrasonic inspection of the fan blade root within 340 cycles since the last inspection.

The actions are required to be completed in accordance with the service bulletin described previously.

Immediate Adoption

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.

Comments Invited

Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications should identify the Rules Docket number and be submitted in triplicate to the address specified under the caption ADDRESSES. All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2000-NE-05-AD.” The postcard will be date stamped and returned to the commenter.

Regulatory Impact

This proposed rule does not have federalism implications, as defined in Executive Order 13132, because it 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. Accordingly, the FAA has not consulted with state authorities prior to publication of this proposed rule.

The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a “significant regulatory action” under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, pursuant to 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.

2. Section 39.13 is amended by adding the following new airworthiness directive:

2000-13-05 Rolls-Royce plc: Amendment 39-11804. Docket 2000-NE-05-AD.

Applicability

This AD is applicable to Rolls-Royce plc. (RR) RB211 Trent 768-60, Trent 772-60, and Trent 772B-60 turbofan engines with fan blade part numbers (P/N's) FK22580, FK23411, FK25441, and FK25968 installed. These engines are installed on but not limited to Airbus A330-341 and A330-342 series airplanes.

Note 1:

This airworthiness directive (AD) applies to each engine identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance

Compliance with this AD is required as indicated below, unless already completed.

To prevent possible multiple fan blade failures, which could result in an uncontained engine failure and damage to the airplane, do the following:

Ultrasonic Inspections

(a) Ultrasonically inspect the dovetail roots of all fan blade P/N's FK22580, FK23411, FK25441, and FK25968 with more than 2800 cycles since new (CSN), for cracks as follows:

Initial Inspection

(1) Initially inspect the fan blade in accordance with paragraph 3.A.(1) or paragraph 3.B.(1) through paragraph 3.B.(8) of RR service bulletin (SB) No. RB.211-72-C878, revision 1, dated December 10, 1999, at the later of the following:

(i) Within 200 fan blade cycles in service (CIS) after the effective date of this AD; or

(ii) Within 200 fan blade CIS of achieving 2800 CSN.

Repetitive Inspections

(2) Thereafter, inspect at intervals not to exceed 340 CIS, since last inspection, in accordance with paragraph 3.A.(1) or paragraph 3.B.(1) through paragraph 3.B.(8) of RR SB No. RB.211-72-C878, revision 1, dated December 10, 1999.

Alternative Methods of Compliance

(b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Engine Certification Office (ECO). Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, ECO.

Note 2:

Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the ECO.

Special Flight Permits

(c) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

Incorporation by Reference Material

(d) The actions required by this AD shall be performed in accordance with the following service documents:

This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Rolls-Royce plc, PO Box 31, Derby, England; telephone: 011-44-1332-249428; fax: 011-44-1332-249223. Copies may be inspected at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Effective Date of This AD

(e) This amendment becomes effective on August 2, 2000.