[Federal Register Volume 69, Number 43 (Thursday, March 4, 2004)]
[Proposed Rules]
[Pages 10179-10181]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-4799]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 69, No. 43 / Thursday, March 4, 2004 / 
Proposed Rules  

[[Page 10179]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NE-54-AD]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce plc RB211 Trent 800 Series 
Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for Rolls-Royce plc (RR) RB211-Trent 800 series turbofan engines. This 
proposal would require revising the Time Limits Manual for RR RB211-
Trent 800 series turbofan engines. These revisions would include 
required enhanced inspection of selected critical life-limited parts at 
each piece-part exposure. This proposal results from the need to 
require enhanced inspection of selected critical life-limited parts of 
RB211-Trent 800 series turbofan engines. We are proposing 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: We must receive any comments on this proposed AD by May 3, 2004.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD:
    [sbull] By mail: Federal Aviation Administration (FAA), New England 
Region, Office of the Regional Counsel, Attention: Rules Docket No. 
2003-NE-54-AD, 12 New England Executive Park, Burlington, MA 01803-
5299.
    [sbull] By fax: (781) 238-7055.
    [sbull] By e-mail: [email protected].
    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:

Comments Invited

    We invite you to submit any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``AD Docket No. 2003-NE-54-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 proposed 
AD. If a person contacts us verbally, and that contact relates to a 
substantive part of this proposed 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 proposed 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 that affect 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.

Discussion

    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 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 would become mandatory for those parts 
listed in the

[[Page 10180]]

compliance section as a result of this proposed AD. Furthermore, we 
intend that additional mandatory enhanced inspections resulting from 
this AD would 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 proposed AD would:
    [sbull] 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.
    [sbull] Allow the air carrier or maintenance facility to retain the 
maintenance records that include the inspections resulting from this 
proposed AD, if the records include the date and signature of the 
person who performed the maintenance action.
    [sbull] Require retaining the records with the maintenance records 
of the part, engine module, or engine until the task is repeated.
    [sbull] Establish a method of record preservation and retrieval 
typically used in existing continuous airworthiness maintenance 
programs.
    [sbull] 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 proposed AD, you would 
not need to perform the mandatory enhanced inspections until the next 
piece-part opportunity. For example, you would 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 
proposed 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 proposed AD. For piece parts not approved for 
return to service before the effective date of this AD, the proposed AD 
would require that you perform the mandatory enhanced inspections 
before approval of those parts for return to service. The proposed AD 
would allow installation of piece parts approved for return to service 
before the effective date of this AD. However, the proposed AD would 
require an enhanced inspection at the next piece-part opportunity.
    This proposal would require, within the next 40 days after the 
effective date of this proposed AD, revisions to the Time Limits 
Manual.

FAA's Determination and Requirements of the Proposed AD

    Since an unsafe condition has been identified that is likely to 
exist or develop on other Rolls-Royce plc RR RB211 Trent 800 series 
turbofan engines of the same type design that are used on Boeing 777 
airplanes registered in the United States, the proposed AD would 
require revisions to the Time Limits Manual for RR RB211-Trent 800 
series turbofan engines to include required enhanced inspection of 
selected critical parts at each piece-part exposure.

Changes to 14 CFR Part 39--Effect on the Proposed AD

    On July 10, 2002, we issued a new version of 14 CFR part 39 (67 FR 
47998, July 22, 2002), which governs the FAA's AD system. This 
regulation now includes material that relates to altered products, 
special flight permits, and alternative methods of compliance. 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.

Costs of Compliance

    There are about 350 engines of the affected design in the worldwide 
fleet. We estimate that 90 engines installed on airplanes of U.S. 
registry would be affected by this proposed AD. We also estimate that 
it would take about 75 work hours per engine to perform the proposed 
inspections, and that the average labor rate is $65 per work hour. 
Since this is an added inspection requirement, included as part of the 
normal maintenance cycle, no additional part costs are involved. Based 
on these figures, the total cost impact of the proposed AD on U.S. 
operators is estimated to be $438,750.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify that the proposed 
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. Would 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 proposal 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-54-AD'' in your request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 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. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive:

Rolls-Royce plc: Docket No. 2003-NE-54-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by May 3, 2004.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Rolls-Royce plc (RR) RB211-Trent 800 
series turbofan engines. These engines are installed on, but not 
limited to, Boeing 777 airplanes.

Unsafe Condition

    (d) This AD results from the need to require enhanced inspection 
of selected critical life-limited parts of RB211-Trent 800 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.

[[Page 10181]]

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.
    (1) 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:
    (i) When the component has been completely disassembled to 
piece-part level as given in the applicable disassembly procedures 
contained in the Engine Manual; and
    (ii) The part has more than 100 recorded flight cycles in 
operation since the last piece-part inspection; or
    (iii) The component removal was for damage or a cause directly 
related to its removal; or
    (iv) Where serviceable used components, for which the inspection 
history is not fully known, are to be used again.
    (2) The list of Group A Parts is specified below:

------------------------------------------------------------------------
                                                  Inspected per overhaul
      Part nomenclature           Part number          manual task
------------------------------------------------------------------------
Low Pressure Compressor Rotor  All.............         72-31-16-200-801
 Disc.
Low Pressure Compressor Rotor  All.............         72-31-20-200-801
 Shaft.
Intermediate Pressure          All.............         72-32-31-200-801
 Compressor Rotor Shaft.
Intermediate Pressure Rear     All.............         72-33-21-200-801
 Shaft.
High Pressure Compressor       All.............         72-41-31-200-801
 Stage 1 to 4 Rotor Discs
 Shaft.
High Pressure Compressor       All.............         72-41-31-200-802
 Stage 5 & 6 Discs and Cone.
High Pressure Turbine Rotor    All.............         72-41-51-200-801
 Disc.
Intermediate Pressure Turbine  All.............         72-51-31-200-801
 Rotor Disc.
Intermediate Pressure Turbine  All.............         72-51-33-200-801
 Rotor Shaft.
Low Pressure Turbine Stage 1   All.............         72-52-31-200-801
 Rotor Disc.
Low Pressure Turbine Stage 2   All.............         72-52-31-200-802
 Rotor Disc.
Low Pressure Turbine Stage 3   All.............         72-52-31-200-803
 Rotor Disc.
Low Pressure Turbine Stage 4   All.............         72-52-31-200-804
 Rotor Disc.
Low Pressure Turbine Stage 5   All.............         72-52-31-200-805
 Rotor Disc.
Low Pressure Turbine Rotor     All.............         72-52-33-200-801
 Shaft.
------------------------------------------------------------------------

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.
    (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 No. G-2003-0003, dated November 
25, 2003, also addresses the subject of this AD.

    Issued in Burlington, Massachusetts, on February 25, 2004.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 04-4799 Filed 3-3-04; 8:45 am]
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