[Federal Register: March 18, 2004 (Volume 69, Number 53)]
[Rules and Regulations]               
[Page 12783-12786]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr18mr04-2]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NE-56-AD; Amendment 39-13525; AD 2004-05-30]
RIN 2120-AA64

 
Airworthiness Directives; Rolls-Royce plc RB211 Trent 500 Series 
Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
Rolls-Royce plc (RR) RB211-Trent 500 series turbofan engines. This AD 
requires revising the Time Limits Manual for RR RB211 Trent 500 series 
turbofan engines. These revisions include required enhanced inspection 
of selected critical life-limited parts at each piece-part exposure. 
This AD results from the need to require enhanced inspection of 
selected critical life-limited parts of RR Trent 500 series turbofan 
engines. We are issuing this AD to prevent failure of critical life-
limited rotating engine parts, which could result in an uncontained 
engine failure and damage to the airplane.

DATES: Effective April 2, 2004.
    We must receive any comments on this AD by May 17, 2004.

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-56-AD, 12 New England Executive Park, 
Burlington, MA 01803-5299.
     By fax: (781) 238-7055.
     By e-mail: 9-ane-adcomment@faa.gov.
    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: Christopher Spinney, Aerospace 
Engineer, Engine Certification Office, FAA, Engine and Propeller 
Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; 
telephone (781) 238-7175, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: A recent FAA study analyzing 15 years of 
accident data for transport category airplanes identified several root 
causes for a failure mode that can result in

[[Page 12784]]

serious safety hazards to transport category airplanes. This study 
identified uncontained failure of critical life-limited rotating engine 
parts as the leading engine-related safety hazard to airplanes. 
Uncontained engine failures have resulted from undetected cracks in 
rotating parts that started and grew to failure. Cracks can start from 
causes such as unintended excessive stress from the original design, or 
they may start from stresses induced from material flaws, handling, or 
damage from machining operations. The failure of a rotating part can 
present a significant safety hazard to the airplane by release of high-
energy fragments that could injure passengers or crew by penetration of 
the cabin, damage flight control surfaces, sever flammable fluid lines, 
or otherwise compromise the airworthiness of the airplane.
    Based on these findings, the FAA, with the concurrence of the Civil 
Aviation Authority (CAA), which is the Airworthiness Authority for the 
United Kingdom (U.K.), has developed an intervention strategy to 
significantly reduce uncontained engine failures. This intervention 
strategy was developed after consultation with industry and will be 
used as a model for future initiatives. The intervention strategy is to 
conduct enhanced, nondestructive inspections of rotating parts, which 
could most likely result in a safety hazard to the airplane in the 
event of a part fracture. We are considering the need for additional 
rulemaking. We might issue future ADs to introduce additional 
intervention strategies to further reduce or eliminate uncontained 
engine failures.
    Properly focused enhanced inspections require identification of the 
parts whose failure presents the highest safety hazard to the airplane, 
identifying the most critical features to inspect on these parts, and 
utilizing inspection procedures and techniques that improve crack 
detection. The CAA, with close cooperation of RR, has completed a 
detailed analysis that identifies the most safety significant parts and 
features, and the most appropriate inspection methods.
    Critical life-limited high-energy rotating parts are currently 
subject to some form of recommended crack inspection when exposed 
during engine maintenance or disassembly. The inspections currently 
recommended by the manufacturer will become mandatory for those parts 
listed in the compliance section as a result of this AD. Furthermore, 
we intend that additional mandatory enhanced inspections resulting from 
this AD will serve as an adjunct to the existing inspections. We have 
determined that the enhanced inspections will significantly improve the 
probability of crack detection on disassembled parts during 
maintenance. All mandatory inspections must be conducted in accordance 
with detailed inspection procedures prescribed in the manufacturer's 
Engine Manual.
    Additionally, this AD will:
     Allow air carriers that operate under the 
provisions of 14 CFR part 121 with an FAA-approved continuous 
airworthiness maintenance program, and maintenance facilities to verify 
completion of the enhanced inspections.
     Allow the air carrier or maintenance facility to 
retain the maintenance records that include the inspections resulting 
from this AD, if the records include the date and signature of the 
person who performed the maintenance action.
     Require retaining the records with the 
maintenance records of the part, engine module, or engine until the 
task is repeated.
     Establish a method of record preservation and 
retrieval typically used in existing continuous airworthiness 
maintenance programs.
     Require adding instructions in an air carrier's 
maintenance manual on how to implement and integrate this record 
preservation and retrieval system into the air carrier's record keeping 
system.
    For engines or engine modules that are approved for return to 
service by an authorized FAA-certificated entity, and that are acquired 
by an operator after the effective date of the AD, you will not need to 
perform the mandatory enhanced inspections until the next piece-part 
opportunity. For example, you will not have to disassemble to piece-
part level, an engine or module returned to service by an FAA-
certificated facility simply because that engine or module was 
previously operated by an entity not required to comply with this AD. 
Furthermore, we intend that operators perform the enhanced inspections 
of these parts at the next piece-part opportunity after the initial 
acquisition, installation, and removal of the part after the effective 
date of this AD. For piece parts not approved for return to service 
before the effective date of this AD, the AD requires that you perform 
the mandatory enhanced inspections before approval of those parts for 
return to service. The AD allows installation of piece parts approved 
for return to service before the effective date of this AD. However, 
the AD requires an enhanced inspection at the next piece-part 
opportunity.
    This AD requires, within the next 40 days after the effective date 
of this AD, revisions to the Time Limits Manual.

FAA's Determination and Requirements of This AD

    Although no airplanes that are registered in the United States use 
these engines, the possibility exists that the engines could be used on 
airplanes that are registered in the United States in the future. The 
unsafe condition described previously is likely to exist or develop on 
other RR RB211 Trent 500 series turbofan engines of the same type 
design. We are issuing this AD to prevent critical life-limited 
rotating engine part failure, which could result in an uncontained 
engine failure and damage to the airplane.

FAA's Determination of the Effective Date

    Since there are currently no domestic operators of this engine 
model, notice and opportunity for public comment before issuing this AD 
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 
47998, 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-56-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 verbal communication, and that contact relates to a substantive part

[[Page 12785]]

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.faa.gov/language and http://www
.plainlanguage.gov.

Examining the AD Docket

    You may examine the AD Docket (including any comments and service 
information), by appointment, between 8 a.m. and 4:30 p.m., Monday 
through Friday, except Federal holidays. See ADDRESSES for the 
location.

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-56-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

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

2004-05-30 Rolls-Royce plc: Amendment 39-13525. Docket No. 2003-NE-
56-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective April 2, 
2004.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Rolls-Royce plc (RR) Trent 500 series 
turbofan engines. These engines are installed on, but not limited 
to, Airbus A340 series airplanes.

Unsafe Condition

    (d) This AD results from the need to require enhanced inspection 
of selected critical life-limited parts of RR Trent 500 series 
turbofan engines. We are issuing this AD to prevent critical life-
limited rotating engine part failure, which could result in an 
uncontained engine failure and damage to the airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified unless the 
actions have already been done.
    (f) Within the next 40 days after the effective date of this AD, 
revise the Time Limits Manual (TLM), and for air carrier operations 
revise the approved continuous airworthiness maintenance program, by 
adding the following:

``GROUP A PARTS MANDATORY INSPECTION

    B. Inspections referred to as `Focus Inspect' in the applicable 
Engine Manual inspection Task are mandatory inspections for the 
components given below, when the conditions that follow are 
satisfied:
    (1) When the component has been completely disassembled to piece 
part level as given in the applicable disassembly procedures 
contained in the Engine Manual; and
    (2) The part has more than 100 recorded flight cycles in 
operation since the last piece part inspection; or
    (3) The component removal was for damage or a cause directly 
related to its removal; or
    (4) Where serviceable used components, for which the inspection 
history is not fully known, are to be used again.
    C. The list of Group A Parts is specified below:

----------------------------------------------------------------------------------------------------------------
            Part nomenclature                       Part No.               Inspected per overhaul manual task
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Low Pressure Compressor Rotor Disk......  All........................  72-31-16-200-801
Low Pressure Compressor Rotor Shaft.....  All........................  72-31-20-200-801
Intermediate Pressure Compressor Rotor    All........................  72-32-31-200-801
 Shaft.
Intermediate Pressure Rear Shaft........  All........................  72-33-21-200-801
High Pressure Compressor Stage 1 to 4     All........................  72-41-31-200-803
 Rotor Disks Shaft.
High Pressure Compressor Stage 5 & 6      All........................  72-41-31-200-801
 Disks and Cone.
High Pressure Turbine Rotor Disk........  All........................  72-41-51-200-801
High Pressure Turbine Front Coverplate..  All........................  72-41-51-200-806
Intermediate Pressure Turbine Rotor Disk  All........................  72-51-31-200-801
Intermediate Pressure Turbine Rotor       All........................  72-51-33-200-801
 Shaft.
Low Pressure Turbine Stage 1 Rotor Disk.  All........................  72-52-31-200-801
Low Pressure Turbine Stage 2 Rotor Disk.  All........................  72-52-31-200-802
Low Pressure Turbine Stage 3 Rotor Disk.  All........................  72-52-31-200-803
Low Pressure Turbine Stage 4 Rotor Disk.  All........................  72-52-31-200-804
Low Pressure Turbine Stage 5 Rotor Disk.  All........................  72-52-31-200-805
Low Pressure Turbine Rotor Shaft........  All........................  72-52-33-200-801''
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Alternative Methods of Compliance

    (g) You must perform these mandatory inspections using the TLM 
and the applicable Engine Manual unless you receive approval to use 
an alternative method of compliance under paragraph (h) of this AD. 
Section 43.16 of the Federal Aviation Regulations (14 CFR 43.16) may 
not be used to approve alternative methods of compliance or 
adjustments to the times in which these inspections must be 
performed.

[[Page 12786]]

    (h) The Manager, Engine Certification Office, has the authority 
to approve alternative methods of compliance for this AD if 
requested using the procedures found in 14 CFR 39.19.

Maintaining Records of the Mandatory Inspections

    (i) You have met the requirements of this AD by using a TLM 
changed as specified in paragraph (f) of this AD, and, for air 
carriers operating under part 121 of the Federal Aviation 
Regulations (14 CFR part 121), by modifying your continuous 
airworthiness maintenance plan to reflect those changes. You must 
maintain records of the mandatory inspections that result from those 
changes to the TLM according to the regulations governing your 
operation. You do not need to record each piece-part inspection as 
compliance to this AD. For air carriers operating under part 121, 
you may use either the system established to comply with section 
121.369 or use an alternative system that your principal maintenance 
inspector has accepted if that alternative system:
    (1) Includes a method for preserving and retrieving the records 
of the inspections resulting from this AD; and
    (2) Meets the requirements of section 121.369(c); and
    (3) Maintains the records either indefinitely or until the work 
is repeated.
    (j) These record keeping requirements apply only to the records 
used to document the mandatory inspections required as a result of 
revising the Time Limits Manual as specified in paragraph (f) of 
this AD, and do not alter or amend the record keeping requirements 
for any other AD or regulatory requirement.

Related Information

    (k) CAA airworthiness directive G-2003-0005, dated September 18, 
2003, also addresses the subject of this AD.

    Issued in Burlington, Massachusetts, on March 5, 2004.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 04-5620 Filed 3-17-04; 8:45 am]

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