AD 2002-11-08

This amendment adopts a new airworthiness directive (AD) that is applicable to Rolls-Royce plc (RR) RB211 Trent 875, 877, 884, 892, 892B, and 895 series turbofan engines with certain part number (P/N) low pressure compressor (LPC) fan blades installed. This action requires initial and repetitive ultrasonic inspection of the fan blade dovetail roots. This amendment is prompted by the loss of an LPC fan blade during takeoff. The actions specified in this AD are intended to prevent multiple LPC fan blade failures due to cracks, which could result in uncontained engine failure and possible damage to the airplane.

Final rule; request for comments.

2002-11-08 Rolls-Royce plc: Amendment 39-12769. Docket No. 2001-NE-17-AD.

Applicability

This airworthiness directive (AD) is applicable to Rolls-Royce plc. (RR) RB211 Trent 875, 877, 884, 892, 892B, and 895 series turbofan engines with low pressure compressor (LPC) fan blades, part numbers (P/N's) FK30838, FK30840, FK30842, FW12960, FW12961, FW12962, and FW13175, installed. These engines are installed on, but not limited to, Boeing Company 777 series airplanes.

Note 1: This 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 (h) of this AD. The request should include an assessment of the effect ofthe 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, unless already done.

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

(a) Ultrasonic-inspect and disposition the dovetail roots of LPC fan blades, P/N's FK30838, FK30840, FK30842, FW12960, FW12961, FW12962, and FW13175, that are removed from the engine, in accordance with 3.A.(1) through 3.A.(5) or, for blades that are not removed from the engine, in accordance with 3.B.(1) through 3.B.(5) of the Accomplishment Instructions of RR service bulletin (SB) RB.211-72-D344, Revision 4, dated March 15, 2002.

(b) For blades P/N's FK30838, FK30840, and FK30842, that have not been relubricated using either RR SB RB.211-72-D344 or RB.211-72-D347, during any interval exceeding 600 cycles-since-new (CSN) or cycles-since-rework (CSR), inspect in accordance with paragraph (a) of this AD and within the compliance times specified in the following Table 1:

TABLE 1

Engine series
Boeing 777 series (IGW)
Airplane maximum gross weight (times 1000 pounds)
Initial inspection (CSN)
Repetitive inspection (cycles-since-last- inspection (CSLI)
(1) -892
-300
(i) 660 and 632.5
(ii) 580
600
2,000
80
600
(2) -884, -892, -892B, and -895

-200 with IGW
(i) 632.5 and 648

(ii) 656
(iii) 555
1,200

600
2,000
100

80
600
(3) -875
-200
535
2,000
600
(4) -877
-200
545
2,000
600

(c) For blades P/N's FK30838, FK30840, and FK30842, that have been relubricated at intervals not exceeding 600 CSN or CSR using either RR SB RB.211-72-D344 or SB RB.211-72-D347, inspect in accordance with paragraph (a) of this AD and within the compliance times specified in the following Table 2:

TABLE 2

Engine series
Boeing 777 series (IGW)
Airplane maximum gross weight (times 1000 pounds)
Initial inspection (CSN)
Repetitive inspection (cycles-since-last-
inspection (CSLI)
(1) -892
-300
(i) 660 and 632.5
(ii) 580
600
2,400
80
600
(2) -884, -892, -892B, and -895
-200 with IGW
(i) 632.5 and 648

(ii) 656
(iii) 555
2,400

600
2,400
100

80
600
(3) -875
-200
535
2,400
600
(4) -877
-200
545
2,400
600

(d) For blades P/N's FW12960, FW12961, FW12962, and FW13175, either new or reworked to that configuration at greater than 600 CSN or since previous rework, or that have not been relubricated during any interval exceeding 600 CSN or CSR using either RR SB RB.211-72-D344 or RB.211-72-D347 requirements, inspect in accordance with paragraph (a) of this AD and within the compliance times specified in the following Table 3:

TABLE 3

Engine series
Boeing 777 series (IGW)
Airplane maximum gross weight (times 1000 pounds)Initial inspection (CSN)
Repetitive inspection
(CSLI)
(1) -892
-300
(i) 660 and 632.5
(ii) 580
600
2000
100
600
(2) -884, -892, -892B, and -895
-200 with IGW
(i) 632.5 and 648

(ii) 656
(iii) 555
1200

600
2000
125

100
600
(3) -875
-200
535
2000
600
(4) -877
-200
545
2000
600

(e) For blades P/N's FW12960, FW12961, FW12962, and FW13175, either new or reworked to that configuration at fewer than 600 CSN or since previous rework, and that have been relubricated using either RR SB RB.211-72-D344 or SB RB.211-72-D347 at intervals not exceeding 600 CSN or repetitive lubrication, inspect in accordance with paragraph (a) of this AD and within the compliance times specified in the following Table 4:

TABLE 4

Engine series
Boeing 777 series (IGW)
Airplane maximum gross weight (times 1000 pounds)
Initial inspection (CSN)
Repetitive inspection
(CSLI)
(1) -892
-300
(i) 660 and 632.5
(ii) 580
600
2400
100
1200

(2) -884, -892,-892B, and -895

(3) -875
-200 with IGW

-200
(i) 632.5 and 648

(ii) 656
(iii) 555
535
2400

600
2400
2400
125

100
1200
1200
(4) -877
-200
545
2400
1200

(f) When engines containing blades P/N's FK30838, FK30840, FK30842, FW12960, FW12961, FW12962, and FW13175 are moved from one gross weight category to another, the inspection schedule that is applicable to the higher gross weight category must be used.

Optional Terminating Action

(g) Replacement of LPC fan blades P/N's FK30838, FK30840, FK30842, FW12960, FW12961, FW12962, and FW13175 with a complete set of LPC fan blades that have a P/N that is not listed in this AD constitutes terminating action for the repetitive inspection requirements of paragraphs (a) through (e) of this AD.

Alternative Methods of Compliance

(h) 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 must 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

(i) Special flight permits may be issued in accordance with Secs. 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 done.

Documents That Have Been Incorporated By Reference

(j) The inspection must be done in accordance with Rolls-Royce plc. (RR) service bulletin RB.211-72-D344, Revision 4, dated March 15, 2002. 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 P.O. Box 31, Derby DE24 6BJ, UK; Telephone 44 (0) 1332 242424; fax 44 (0) 1332 249936. Copies may be inspected, by appointment, 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.

Note 3: The subject of this AD is addressed in CAA airworthiness directive 001-02-2001, dated February 2, 2000.

Effective Date

(k) This amendment becomes effective on June 21, 2002.

The Civil Aviation Authority (CAA), which is the airworthiness authority for the United Kingdom (UK), recently notified the FAA that an unsafe condition may exist on RR RB211 Trent 875, 877, 884, 892, 892B, and 895 series turbofan engines with certain P/N LPC fan blades installed. The CAA advises there has been an incident involving the loss of an LPC fan blade during takeoff. The release of the blade occurred as the result of the initiation and propagation of a crack in the LPC fan blade root, convex side, located on either side of the shear key slot. A subsequent "around the fleet inspection" revealed a similar condition in four additional LPC fan blades. The effects of dry film lubrication and improved blade root lubrication (Metco 58) were determined to be critical in preventing the initiation of cracking in the root of the LPC fan blade. In addition, blade root configurations, airplane type, and engine ratings were found to affect initial and repetitiveinspection requirements.

Manufacturer's Service Information

RR has issued service bulletin (SB) RB.211-72-D344, Revision 4, dated March 15, 2002, that provides procedures to ultrasonic-inspect the blade root on LPC fan blades. The CAA classified this service bulletin as mandatory and issued AD 001-02-2001, dated February 2, 2000, in order to assure the airworthiness of these RR engines in the UK.

Bilateral Airworthiness Agreement

This engine model is manufactured in the UK and is type certificated for operation in the United States under the provisions of Sec. 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 foroperation in the United States.

FAA's Determination of an Unsafe Condition and Required Actions

Since an unsafe condition has been identified that is likely to exist or develop on other RR RB211 Trent 875, 877, 884, 892, 892B, and 895 series turbofan engines of the same type design, this AD is being issued to prevent multiple LPC fan blade failures due to cracks, which could result in uncontained engine failure and possible damage to the airplane. This AD requires ultrasonic inspection of the dovetail roots of LPC fan blades P/N's FK30838, FK30840, FK30842, FW12960, FW12961, FW12962, and FW13175. The actions must be done in accordance with the service bulletin described previously.

Immediate Adoption of This AD

Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days.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 thatmight 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 action must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 2001-NE-17-AD." The postcard will be date stamped and returned to the commenter.

Regulatory Analysis

This final 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 final 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 delegatedto 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.

Sec. 39.13 [Amended]

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