AD 2002-10-15 SUPERSEDED

This amendment adopts a new airworthiness directive (AD), that is applicable to Rolls-Royce plc RB211 Trent 875, 877, 884, 892, 892B, and 895 series turbofan engines. This amendment requires reapplication of dry film lubricant to low pressure compressor (LPC) fan blade roots. This amendment is prompted by an aborted take-off resulting from LPC fan blade loss. Since this event, four additional cracked LPC fan blade roots have been reported. The actions specified by this AD are intended to prevent LPC fan blade loss, which could result in an uncontained engine failure and possible aircraft damage.

Final rule.

2002-10-15 Rolls-Royce plc: Amendment 39-12761. Docket No. 2001-NE-12-AD.

Applicability

This airworthiness directive (AD) is applicable to Rolls-Royce plc RB211 Trent 875, 877, 884, 892, 892B, and 895 series turbofan engines with low pressure compressor (LPC) fan blade part numbers: FK 30838, FK30840, FK30842, FW12960, FW12961, FW12962, FW13175, or FW18548. These engines are installed on, but not limited to Boeing 777 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 (c) of this AD. The request should include an assessment of the effect of the modification, alteration, orrepair 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 LPC fan blade loss, which could result in an uncontained engine failure and possible aircraft damage, do the following:

Table 1.7-Initial and Repetitive Application Thresholds

LPC fan blade part Nos.
Initial compliance criteria
Repetitive compliance criteria
FK30842, FK30840, and FK30838
Before achieving 600 cycles-since-new or -last application.
Repeat at intervals not exceeding 600 cycles-since-last compliance
FW12961, FW12960, FW12962, FW13175, and FW18548.
Before achieving 1,200 cycles-since-new or -last application.
Repeat at intervals not exceeding 1,200 cycles-since-last compliance.

(a) Apply an approved dry film lubricant to LPC fan blade roots as specified in Table 1 above. Aircraft Maintenance Manual task 72-31-11-300-801-R00 (Repair Scheme FRS A031 by air spray method only) or Engine Manual task 72-31-11-R001 (Repair Scheme FRS A028) contain procedures for renewing the dry film lubricant on the blade roots. For purposes of this AD, approved lubricants are Dow Corning 321R (Rolls-Royce (RR) Omat item 4/51), Rocol Dry Moly Spray (RR Omat item 4/52), Molydag 709 (RR Omat item 444), or PL.237/R1 (RR Omat item 4/43).

Fan Blades Exceeding Initial Application Thresholds

(b) On the effective date of the AD, blades with more cycles than the initial compliance criteria listed in Table 1 of this AD must be lubricated within 100 cycles-in-service after the effective date of this AD.

Alternative Methods of Compliance

(c) 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 request 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

(d) 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 aircraft to a location where the requirements of this AD can be done.

Note 3: The subject of this AD is addressed in Civil Aviation Authority Airworthiness Directive 001-03-2001, dated March 2, 2001.

Effective Date

(e) This amendment becomes effective on July 2, 2002.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that is applicable to Rolls-Royce plc RB211 Trent 875, 877, 884, 892, 892B, and 895 series turbofan engines was published in the Federal Register on December 6, 2001 (66 FR 63341). That action proposed to require reapplication of dry film lubricant to low pressure compressor (LPC) fan blade roots.

Comments

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

Wording Clarification

One commenter suggests that the word "installation" in Table 1 of the compliance section, be replaced with the words "new or last lubrication." The commenter is concerned that the word "installation" does not ensure AD compliance at installation.

The FAA agrees. The wording in Table 1 has been changed because the suggested wording ensures that lubrication of the blade root is the proper criteria to use.

Typographical Errors

One commenter requests "LPT" be changed to correctly read "LPC" in Table 1, and "Dow Corning 321R (Rolls-Royce (RR) Omat item 4/52)" be changed to correctly read Dow Corning 321R (Rolls-Royce (RR) Omat item 4/51)" in paragraph (a).

The FAA agrees and has made these corrections in the final rule.

Update Terminology

One commenter suggests that the word "inspect" is not applicable in paragraph (b), and should be replaced with the word "lubricate." The AD is applicable to blade root lubrication.

The FAA agrees and has changed paragraph (b) in the final rule to state that on the effective date of the AD, blades with more cycles than the initial compliance criteria listed in Table 1 of this AD must be lubricated within 100 cycles-in-service after the effective date of this AD.

After careful review of the available data, including the comments noted above, the FAA has determined that air safetyand the public interest require the adoption of the rule with the changes described previously. The FAA has determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

Economic Analysis

The FAA estimates that 100 engines installed on aircraft of U.S. registry would be affected by this AD. The FAA also estimates that it would take approximately 6 work hours per engine to accomplish the proposed actions, and that the average labor rate is $60 per work hour. Based on these figures, the total labor cost of the AD on U.S. operators is estimated to be $36,000 to accomplish each application of lubricant. The FAA estimates that operators will apply lubricant an average of 1.5 times per year, making the total annual cost of compliance with this AD $54,000.

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.

For the reasons discussed above, I certify that this action (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) if promulgated, 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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, 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.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding a new airworthiness directive to read as follows:

Information regarding this action may be examined, by appointment, at the Federal Aviation Administration (FAA), New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA.

Keith Mead, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone: (781) 238-7744, fax: (781) 238-7199.