Document ID: FAA-2010-0755-0007
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Rolls-Royce plc (RR) RB211-Trent 800 Series Turbofan Engines
Posted Date: 2011-11-07T05:00Z

[Federal Register Volume 76, Number 215 (Monday, November 7, 2011)]
[Proposed Rules]
[Pages 68663-68665]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-28678]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0755; Directorate Identifier 2010-NE-12-AD]
RIN 2120-AA64

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

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (NPRM); reopening of 
comment period.

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SUMMARY: We are revising an earlier proposed airworthiness directive 
(AD) for RR RB211-Trent 800 series turbofan engines. That NPRM proposed 
to revise the Trent 800 Time Limits Manual (TLM) of the Trent 800 
engine maintenance manuals (EMMs). That NPRM was prompted by RR 
reducing the life limits of certain critical engine parts. This action 
revises that NPRM by proposing to supersede an existing AD to prohibit 
installation of one certain critical part and to increase the life of 
another critical part whose lives were previously reduced by that 
existing AD. We are proposing this supplemental NPRM to prevent the 
failure of critical rotating parts, which could result in uncontained 
failure of the engine and damage to the airplane. Because of the 
extensive changes since the NPRM was issued, we are reopening the 
comment period to allow the public the chance to comment on these 
proposed changes.

DATES: We must receive comments on this proposed AD by January 6, 2012.

ADDRESSES: You may send comments using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: (202)-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact Rolls-Royce 
plc, Corporate Communications, P.O. Box 31, Derby, England, DE248BJ; 
phone: 011-44-1332-242424; fax: 011-44-1332-245418 or email from http://www.rolls-royce.com/contact/civil_team.jsp, or download the 
publication from https://www.aeromanager.com. You may review copies of 
the referenced service information at the FAA, Engine & Propeller 
Directorate, 12 New England Executive Park, Burlington, MA. For 
information on the availability of this material at the FAA, call 
(781)-238-7125.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (phone: (800) 647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Alan Strom, Aerospace Engineer, Engine

[[Page 68664]]

Certification Office, FAA, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; phone: (781) 238-7143; 
fax: (781) 238-7199; email: alan.strom@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2010-0755; 
Directorate Identifier 2010-NE-12-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD based on those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We issued an NPRM to amend 14 CFR part 39 to include an AD that 
would apply to RR RB211-Trent 800 series turbofan engines. That NPRM 
published in the Federal Register on August 3, 2010 (75 FR 45560). That 
NPRM would have revised the TLM of the RB211-Trent 800 EMMs. That NPRM 
was prompted by RR reducing the life limits of certain critical engine 
parts. Revision of the critical part lives has been necessary due to 
actual operational flight profiles not conforming to those assumed at 
entry into service and is associated with a revised Flight Profile 
Monitoring methodology introduced by RR. The methodology was originally 
based on engine thrust rating but is now based on operating shaft 
speeds.

Actions Since Previous NPRM Was Issued

    Since we issued the previous NPRM (75 FR 45560, August 3, 2010), RR 
requested that we supersede existing AD 2003-16-18, Amendment 39-13271 
(68 FR 49344, August 18, 2003). That AD currently requires a life limit 
for intermediate-pressure (IP) turbine rotor disc, part number (P/N) 
FK21117, that is lower than the life limit proposed by this 
supplemental NPRM. Rolls-Royce plc substantiated their proposed 
increased life of P/N FK21117 by rig test and analysis.
    AD 2003-16-18 (68 FR 49344, August 18, 2003) also reduced the life 
limit for IP turbine rotor discs, P/N FK33083, and all P/N FK33083 IP 
turbine rotor discs are no longer in service. RR has accordingly 
reduced the life for P/N FK33083 discs to zero, effectively removing 
them as a disc approved for installation in any engine. By revising the 
previous NPRM (75 FR 45560, August 3, 2010) to supersede AD 2003-16-18, 
as discussed previously, this proposed AD would make these changes to 
the life of RR IP turbine rotor disc, P/N FK21117, and RR IP turbine 
rotor disc, P/N FK33083, mandatory. We have also determined that it is 
unnecessary to incorporate by reference the TLM of the Trent 800 engine 
EMMs. We can address the unsafe condition identified in this 
supplemental NPRM by mandating the reduced lives of the affected parts.

Comments

    We gave the public the opportunity to comment on the previous NPRM 
(75 FR 45560, August 3, 2010). We have considered the comments 
received.

Request To Change Compliance Paragraph (e)(1)

    American Airlines and Delta Airlines asked us to change paragraph 
(e)(1) in the proposed AD from ``(1) Revise the airworthiness 
limitations section (ALS) * * * Time Limits manual (TLM) dated June 15, 
2009'' to ``(1) Revise the airworthiness limitations section (ALS) * * 
* Time Limits manual (TLM) dated no earlier than June 15, 2009.'' The 
commenters do not want to be forced to use a TLM dated earlier than the 
one currently in force.
    We partially agree. We agree that a more efficient method of 
revising the life exists, so we changed this proposed AD to specify the 
revised part lives in Table 1 in the Compliance section of this 
proposed AD. We do not agree to the requested wording as it leaves 
compliance with the AD open to future revisions that do not currently 
exist. We did not change the proposed AD further as a result of this 
comment.

Request To Withdraw the NPRM

    Delta Airlines asked us to withdraw the NPRM (75 FR 45560, August 
3, 2010). Delta Airlines believed the NPRM is redundant because the 
current TLM already requires using the proposed tasks and life limits.
    We do not agree. Although the new life limits are included in the 
current TLM, the new life limits are reinforced when mandated by an AD. 
We changed this proposed AD to specify the revised part lives in Table 
1 in the Compliance section of this proposed AD.

Request To Supersede the Existing AD 2003-16-18 (68 FR 49344, August 
18, 2003)

    Rolls-Royce plc asked us to change paragraph (b) of the proposed AD 
from ``None'' to ``AD 2003-16-18 is superseded by the current AD.''
    We agree. We changed paragraph (b) of this proposed AD to state 
that ``This AD supersedes AD 2003-16-18, Amendment 39-13271 (68 FR 
49344, August 18, 2003)''.

Relevant Service Information

    Rolls-Royce plc has issued Alert Service Bulletin No. RB.211-72-
AE935, Revision 7, dated January 19, 2009. The actions described in 
this service information are intended to correct the unsafe condition 
identified in this supplemental NPRM.

FAA's Determination

    We are proposing this supplemental NPRM because we evaluated all 
the relevant information and determined the unsafe condition described 
previously is likely to exist or develop in other products of the same 
type design. Certain changes described above expand the scope of the 
previous NPRM (75 FR 45560, August 3, 2010). As a result, we have 
determined that it is necessary to reopen the comment period to provide 
additional opportunity for the public to comment on this supplemental 
NPRM.

Proposed Requirements of the Supplemental NPRM

    This supplemental NPRM would reduce the life limits of certain 
critical engine parts and would supersede AD 2003-16-18, Amendment 39-
13271 (68 FR 49344, August 18, 2003).

Costs of Compliance

    Based on the service information, we estimate that this proposed AD 
would affect about 16 RB211-Trent 800 series turbofan engines of U.S. 
registry. The average labor rate is $85 per work-hour, but no labor 
cost is associated with this proposed AD because discs are replaced at 
scheduled maintenance intervals. Prorated cost of parts would cost 
about $45,000 per engine. Based on these figures, we estimate the cost 
of the proposed AD on U.S. operators to be $720,000.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. ``Subtitle VII: Aviation 
Programs,'' describes in more

[[Page 68665]]

detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
``Subtitle VII, Part A, Subpart III, Section 44701: General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We 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 this 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);
    (3) Will not affect intrastate aviation in Alaska or;
    (4) 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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA 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 removing airworthiness directive 
(AD) 2003-16-18, Amendment 39-13271 (68 FR 49344, August 18, 2003), and 
adding the following new AD:

Rolls-Royce plc: Docket No. FAA-2010-0755; Directorate Identifier 
2010-NE-12-AD.

(a) Comments Due Date

    We must receive comments by January 6, 2012.

(b) Affected ADs

    This AD supersedes AD 2003-16-18, Amendment 39-13271 (68 FR 
49344, August 18, 2003).

(c) Applicability

    This AD applies to Rolls-Royce plc (RR) RB211-Trent 895-17, 892-
17, 892B-17, 884-17, 884B-17, 877-17, and 875-17 turbofan engines.

(d) Unsafe Condition

    This AD was prompted by RR reporting changes to the lives of 
certain life limited rotating parts. We are issuing this AD to 
prevent the failure of critical rotating parts, which could result 
in uncontained failure of the engine and damage to the airplane.

(e) Actions and Compliance

    Compliance is required within 30 days after the effective date 
of this AD, unless already done.
    (1) After the effective date of this AD, remove from service the 
parts listed in Table 1 of this AD before exceeding the new life 
limit indicated:

                                           Table 1--Reduced Part Lives
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                                                                                                 Life in cycles
                   Part nomenclature                     Part number (P/N)   Life in standard   using the HEAVY
                                                                               duty cycles          profile
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(i) Intermediate-pressure (IP) Compressor Rotor Shaft..            FK24100              8,140              8,140
(ii) IP Compressor Rotor Shaft.........................            FK24496              8,860              8,180
(iii) High-pressure (HP) Compressor Stage 1 to 4 Rotor             FK24009              4,560              4,460
 Discs Shaft...........................................
(iv) HP Compressor Stage 1 to 4 Rotor Discs Shaft......            FK26167              6,340              6,000
(v) HP Compressor Stage 1 to 4 Rotor Discs Shaft.......            FK32580              8,550              6,850
(vi) HP Compressor Stage 1 to 4 Rotor Discs Shaft......            FW11590              8,550              6,850
(vii) HP Compressor Stage 1 to 4 Rotor Discs Shaft.....            FW61622              8,550              6,850
(viii) HP Compressor Stage 5 and 6 Discs and Cone......            FK25230              5,000              5,000
(ix) HP Compressor Stage 5 and 6 Discs and Cone........            FK27899              5,000              5,000
(x) IP Turbine Rotor Disc..............................            FK21117             11,610             10,400
(xi) IP Turbine Rotor Disc.............................            FK33083                  0                  0
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(f) Installation Prohibition

    After the effective date of this AD, do not install any IP 
turbine rotor discs, P/N FK33083, into any engine.

(g) Alternative Methods of Compliance (AMOCs)

    The Manager, Engine Certification Office, FAA, may approve AMOCs 
to this AD. Use the procedures found in 14 CFR 39.19 to make your 
request.

(h) Related Information

    (1) You may find additional information on calculating Standard 
Duty Cycles and or using HEAVY Profile Cycles, in RR TLM 05-00-01-
800-801, Recording and Control of the Lives of Parts.
    (2) For more information about this AD, contact Alan Strom, 
Aerospace Engineer, Engine Certification Office, FAA, Engine and 
Propeller Directorate, 12 New England Executive Park, Burlington, MA 
01803; phone: (781) 238-7143; fax: (781) 238-7199; 
email:alan.strom@faa.gov.
    (3) Refer to European Aviation Safety Agency Airworthiness 
Directive 2007-0003R1, dated January 15, 2009, and RR Alert Service 
Bulletin No. RB.211-72-AE935, Revision 7, dated January 19, 2009, 
for related information.

    Issued in Burlington, Massachusetts, on October 31, 2011.
Peter A. White,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-28678 Filed 11-4-11; 8:45 am]
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