[Federal Register Volume 65, Number 21 (Tuesday, February 1, 2000)]
[Rules and Regulations]
[Pages 4760-4761]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-2000]



[[Page 4760]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NE-60-AD; Amendment 39-11535; AD 2000-02-17]
RIN 2120-AA64


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

AGENCY:  Federal Aviation Administration, DOT.

ACTION:  Final rule; request for comments.

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SUMMARY:  This amendment adopts a new airworthiness directive (AD) that 
is applicable to Rolls-Royce plc RB211 Trent 768-60, 772-60, and 772B-
60 series turbofan engines. This action requires initial and repetitive 
visual inspections for flank wear on intermediate pressure turbine 
(IPT) shaft splines and intermediate pressure compressor (IPC) rear 
stub shaft splines. Components that show excessive flank wear must be 
replaced with serviceable parts. This amendment is prompted by reports 
of worn IPT shaft splines discovered at overhaul. The actions specified 
in this AD are intended to prevent IPT and IPC shaft spline flank wear, 
which could result in loss of drive between the IPT and IPC, leading to 
an IPT overspeed and possible disk burst, uncontained engine failure, 
and potential damage to the aircraft.

DATES:  Effective February 16, 2000.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of February 16, 2000.
    Comments for inclusion in the Rules Docket must be received on or 
before April 3, 2000.

ADDRESSES:  Submit comments to the Federal Aviation Administration 
(FAA), New England Region, Office of the Regional Counsel, Attention: 
Rules Docket No. 99-NE-60--AD, 12 New England Executive Park, 
Burlington, MA 01803-5299. Comments may also be sent via the Internet 
using the following address: ``[email protected]''. 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: International 
Access Code 011, Country Code 44, 1332-249428, fax: International 
Access Code 011, Country Code 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 (UK), recently 
notified the Federal Aviation Administration (FAA) that an unsafe 
condition may exist on Rolls-Royce plc (R-R) RB211 Trent 768-60, 772-
60, and 772B-60 series turbofan engines. The CAA advises that it has 
received reports of excessive flank wear discovered on intermediate 
pressure turbine (IPT) shaft splines at overhaul. The investigation 
revealed that a lubrication problem, among other factors, may be 
causing the wear. This condition, if not corrected, could result in IPT 
and intermediate pressure compressor (IPC) shaft spline flank wear, 
which could result in loss of drive between the IPT and IPC, leading to 
an IPT overspeed and possible disk burst, uncontained engine failure, 
and potential damage to the aircraft.

Service Information

    R-R has issued Mandatory Service Bulletin (SB) No. RB.211-72-C329, 
Revision 1, dated November 6, 1998, that specifies procedures and 
references for performing visual inspections for flank wear on IPT 
shaft splines and IPC rear stub shaft splines. The SB also provides 
references for determining if excessive flank wear requires replacing 
worn components with serviceable parts. The CAA classified this SB as 
mandatory and issued airworthiness directive (AD) 004-04-98, dated 
November 6, 1998, in order to assure the airworthiness of these R-R 
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 
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.

Required Actions

    Since an unsafe condition has been identified that is likely to 
exist or develop on other engines of the same type design registered in 
the United States, the AD requires initial visual inspections prior to 
accumulating 4,200 cycles-since-new (CSN) and repetitive inspections at 
intervals not to exceed 4,200 cycles-in-service (CIS) since last 
inspection. Components that show excessive flank wear must be replaced 
with serviceable parts. The actions would be required to be 
accomplished in accordance with the SB described previously.

Immediate Adoption

    There are currently no domestic operators of this engine model. 
Accordingly, a situation exists that allows the immediate adoption of 
this regulation. Notice and opportunity for prior public comment hereon 
are impracticable, and 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 
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

[[Page 4761]]

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 99-NE-60-AD.'' The postcard will be date stamped and 
returned to the commenter.

Regulatory Impact

    The regulations adopted herein 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. Therefore, it 
is determined that this final rule does not have federalism 
implications under Executive Order (EO) 13132.
    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 EO 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.


Sec. 39.13  [Amended]

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

2000-02-17  Rolls-Royce plc: Amendment 39-11535. Docket 99-NE-60-AD.

    Applicability: Rolls-Royce plc (R-R) RB211 Trent Rolls-Royce plc 
(R-R) RB211 Trent 768-60, 772-60, and 772B-60 series turbofan 
engines, installed on but not limited to Airbus Industrie 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 (c) 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: Required as indicated, unless accomplished 
previously.
    To prevent intermediate pressure turbine (IPT) and intermediate 
pressure compressor (IPC) shaft spline flank wear, which could 
result in loss of drive between the IPT and IPC, leading to an IPT 
overspeed and possible disk burst, uncontained engine failure, and 
potential damage to the aircraft, accomplish the following:

Inspections

    (a) Visually inspect for flank wear on IPT shaft splines and 
intermediate pressure compressor IPC rear stub shaft splines in 
accordance with Paragraph D, Action, of R-R Mandatory Service 
Bulletin (SB) No. RB.211-72-C329, Revision 1, dated November 6, 
1998, as follows:
    (1) Initially inspect prior to accumulating 4,200 cycles-since-
new.
    (2) Thereafter, inspect at intervals not to exceed 4,200 cycles-
in-service since last inspection.

Replacement, If Necessary

    (b) If spline wear depth exceeds the limits referred to in 
paragraph D (h)(vi) of R-R Mandatory SB No. RB.211-72-C329, Revision 
1, dated November 6, 1998, prior to further flight remove from 
service worn components and replace with serviceable parts.

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 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 AD, if any, may be 
obtained from the ECO.

Ferry Flights

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

Incorporation by Reference

    (e) The actions required by this AD shall be performed in 
accordance with Rolls-Royce plc Mandatory Service Bulletin No. 
RB.211-72-C329, Revision 1, dated November 6, 1998. 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: International Access Code 011, Country Code 44, 
1332-249428, fax: International Access Code 011, Country Code 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.
    (f) This amendment becomes effective on February 16, 2000.

    Issued in Burlington, Massachusetts, on January 21, 2000.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 00-2000 Filed 1-31-00; 8:45 am]
BILLING CODE 4910-13-U