Airworthiness Directives; Rolls-Royce plc RB211-Trent 800 Series Turbofan Engines, 2605-2607 [2011-775]
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2605
Proposed Rules
Federal Register
Vol. 76, No. 10
Friday, January 14, 2011
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.
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2010–0821; Directorate
Identifier 2010–NE–30–AD]
RIN 2120–AA64
Airworthiness Directives; Rolls-Royce
plc RB211–Trent 800 Series Turbofan
Engines
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking
(NPRM).
AGENCY:
We propose to adopt a new
airworthiness directive (AD) for the
products listed above. This proposed
AD results from mandatory continuing
airworthiness information (MCAI)
issued by an aviation authority of
another country to identify and correct
an unsafe condition on an aviation
product. The MCAI describes the unsafe
condition as:
mstockstill on DSKH9S0YB1PROD with PROPOSALS
SUMMARY:
In January 2009 a Trent 895 powered
Boeing 777–200 aircraft experienced release
of a low pressure (LP) compressor blade
which failed due to fatigue cracking in the
root section of the blade. The released blade
(undercut root standard) had received a part
life processing to apply a compression layer
to the blade root (Service Bulletin SB 72–
D672—Introduction of Laser Shock Peening
(LSP)) and also a part life upgrade to the
retention feature lubrication system.
Investigation has revealed that the
effectiveness of this upgraded blade root
lubrication coating system may be reduced
dependant on the extent of previous running
with the earlier standard, leading to
increased blade root stress levels. In the
specific case of the released blade, a review
of its in-service modification history has
shown that it operated for a relatively high
number of flight cycles prior to the
compression layer processing and the new
retention feature lubrication system. A
review of the Engine Health Monitoring data
has also identified it operated at high N1
speeds compared to the Trent 800 fleet
average N1 speeds. The combination of these
factors has resulted in increased fatigue life
VerDate Mar<15>2010
16:43 Jan 13, 2011
Jkt 223001
usage which is considered to have led to
crack initiation and propagation prior to
reaching the blades declared life limit. A
review of all in-service undercut/LSP
standard Trent 800 LP compressor blades has
identified specific blades that carry a similar
increased susceptibility to cracking.
This AD is issued to mitigate the risk of
possible multiple fan blades failure affecting
those blades identified as described above
which could lead to high energy non
contained debris from the engine.
We are proposing this AD to prevent LP
compressor blades from failing due to
blade root cracks, which could lead to
uncontained engine failure and damage
to the airplane.
DATES: We must receive comments on
this proposed AD by February 28, 2011.
ADDRESSES: You may send comments by
any of the following methods:
• Federal eRulemaking Portal: Go to
https://www.regulations.gov and follow
the instructions for sending your
comments electronically.
• Mail: Docket Management Facility,
U.S. Department of Transportation, 1200
New Jersey Avenue, SE., West Building
Ground Floor, Room W12–140,
Washington, DC 20590–0001.
• Hand Delivery: Deliver to Mail
address above between 9 a.m. and 5
p.m., Monday through Friday, except
Federal holidays.
• Fax: (202) 493–2251.
Contact Rolls-Royce plc, P.O. Box 31,
DERBY, DE24 8BJ, UK; telephone 44 (0)
1332 242424; fax 44 (0) 1332 249936, for
the service information identified in this
proposed AD.
Examining the AD Docket
You may examine the AD docket on
the Internet at https://
www.regulations.gov; or in person at the
Docket Operations office 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 Operations
office (phone (800) 647–5527) is the
same as the Mail address provided in
the ADDRESSES section. Comments will
be available in the AD docket shortly
after receipt.
FOR FURTHER INFORMATION CONTACT:
Alan Strom, Aerospace Engineer, Engine
Certification Office, FAA, Engine &
Propeller Directorate, 12 New England
Executive Park, Burlington, MA 01803;
PO 00000
Frm 00001
Fmt 4702
Sfmt 4702
e-mail: alan.strom@faa.gov; telephone
(781) 238–7143; fax (781) 238–7199.
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–2010–0821; Directorate Identifier
2010–NE–30–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 https://
www.regulations.gov, including any
personal information you provide. We
will also post a report summarizing each
substantive verbal contact with FAA
personnel concerning this proposed AD.
Using the search function of the Web
site, anyone can find and read the
comments in any of our dockets,
including, if provided, the name of the
individual who sent the comment (or
signed the comment on behalf of an
association, business, labor union, etc.).
You may review the DOT’s complete
Privacy Act Statement in the Federal
Register published on April 11, 2000
(65 FR 19477–78).
Discussion
The European Aviation Safety Agency
(EASA), which is the Technical Agent
for the Member States of the European
Community, has issued EASA
Airworthiness Directive 2010–0097,
dated May 26, 2010 (referred to after
this as ‘‘the MCAI’’), to correct an unsafe
condition for the specified products.
The MCAI states:
In January 2009 a Trent 895 powered
Boeing 777–200 aircraft experienced release
of a low pressure (LP) compressor blade
which failed due to fatigue cracking in the
root section of the blade. The released blade
(undercut root standard) had received a part
life processing to apply a compression layer
to the blade root (Service Bulletin SB 72–
D672—Introduction of Laser Shock Peening
(LSP)) and also a part life upgrade to the
retention feature lubrication system.
Investigation has revealed that the
effectiveness of this upgraded blade root
lubrication coating system may be reduced
dependant on the extent of previous running
with the earlier standard, leading to
E:\FR\FM\14JAP1.SGM
14JAP1
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Federal Register / Vol. 76, No. 10 / Friday, January 14, 2011 / Proposed Rules
increased blade root stress levels. In the
specific case of the released blade, a review
of its in-service modification history has
shown that it operated for a relatively high
number of flight cycles prior to the
compression layer processing and the new
retention feature lubrication system. A
review of the Engine Health Monitoring data
has also identified it operated at high N1
speeds compared to the Trent 800 fleet
average N1 speeds. The combination of these
factors has resulted in increased fatigue life
usage which is considered to have led to
crack initiation and propagation prior to
reaching the blades declared life limit. A
review of all in-service undercut/LSP
standard Trent 800 LP compressor blades has
identified specific blades that carry a similar
increased susceptibility to cracking.
This AD is issued to mitigate the risk of
possible multiple fan blades failure affecting
those blades identified as described above
which could lead to high energy non
contained debris from the engine.
You may obtain further information
by examining the MCAI in the AD
docket.
Relevant Service Information
Rolls-Royce plc has issued Alert
Service Bulletin No. RB.211–72–AG244,
Revision 1, dated January 26, 2010. The
actions described in this service
information are intended to correct the
unsafe condition identified in the
MCAI.
FAA’s Determination and Requirements
of This Proposed AD
This product has been approved by
the aviation authority of the United
Kingdom, and is approved for operation
in the United States. Pursuant to our
bilateral agreement with the United
Kingdom, they have notified us of the
unsafe condition described in the MCAI
and service information referenced
above. We are proposing this AD
because we evaluated all information
provided by EASA, and determined the
unsafe condition exists and is likely to
exist or develop on other products of the
same type design.
mstockstill on DSKH9S0YB1PROD with PROPOSALS
Costs of Compliance
Based on the service information, we
estimate that this proposed AD would
affect about 20 engines installed on
airplanes of U.S. registry. We also
estimate that it would take about 18
work-hours per engine to perform the
inspections in one year’s time. The
average labor rate is $85 per work-hour.
We estimate that one LP compressor
blade per year would need replacement,
at a cost of about $82,000. Based on
these figures, we estimate the annual
cost of the proposed AD on U.S.
operators to be $112,600. Our cost
estimate is exclusive of possible
warranty coverage.
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
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); 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 regulatory evaluation
of the estimated costs to comply with
this proposed AD and placed it in the
AD docket.
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.
§ 39.13
[Amended]
2. The FAA amends § 39.13 by adding
the following new AD:
Rolls-Royce plc: Docket No. FAA–2010–
0821; Directorate Identifier 2010–NE–
30–AD.
Comments Due Date
(a) We must receive comments by February
28, 2011.
Affected Airworthiness Directives (ADs)
(b) None.
Applicability
(c) This AD applies to Rolls-Royce plc (RR)
RB211–Trent 875–17, RB211–Trent 877–17,
RB211–Trent 884–17, RB211–Trent 884B–17,
RB211–Trent 892–17, RB211–Trent 892B–17,
and RB211–Trent 895–17 turbofan engines.
Reason
(d) This AD results from mandatory
continuing airworthiness information (MCAI)
issued by an aviation authority of another
country to identify and correct an unsafe
condition on an aviation product. We are
issuing this AD to prevent low-pressure (LP)
compressor blades from failing due to blade
root cracks, which could lead to uncontained
engine failure and damage to the airplane.
Actions and Compliance
(e) Unless already done, do the following
actions.
(1) Using the corresponding compliance
threshold in Table 1 of this AD, perform an
initial ultrasonic inspection (UI) of the
affected LP compressor blades identified by
serial number (S/N) in Appendices 3A
through 3F of RR Alert Service Bulletin
(ASB) No. RB.211–72–AG244, Revision 1,
dated January 26, 2010.
TABLE 1—INITIAL INSPECTION THRESHOLDS
Appendix number of RR ASB No. RB.211–
72–AG244, Revision 1, that identifies affected LP compressor blades by
S/N
3A ...................................................................
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16:43 Jan 13, 2011
Jkt 223001
Initial inspection threshold
120 flight cycles after the effective date of this AD.
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Federal Register / Vol. 76, No. 10 / Friday, January 14, 2011 / Proposed Rules
2607
TABLE 1—INITIAL INSPECTION THRESHOLDS—Continued
Appendix number of RR ASB No. RB.211–
72–AG244, Revision 1, that identifies affected LP compressor blades by
S/N
3B ...................................................................
3C ...................................................................
3D ...................................................................
3E ...................................................................
3F ...................................................................
(2) Thereafter, perform repetitive UIs of the
affected LP compressor blades within every
100 flight cycles.
(3) Use paragraph 3 of Accomplishment
Instructions of RR ASB No. RB.211–72–
AG244, Revision 1, dated January 26, 2010,
and Appendix 1 of that ASB to perform the
UIs.
(4) Remove blades from service before
further flight that fail the inspection criteria
in Appendix 1 of RR ASB No. RB.211–72–
AG244, Revision 1, dated January 26, 2010.
(5) After the effective date of this AD, do
not install any affected LP compressor blade
unless it has passed the initial and repetitive
UIs required by this AD.
FAA AD Differences
Initial inspection threshold
Blades shown in RR ASB No. RB.211–72–AG244, Revision 1 as fitted to engine serial number
(ESN) 51039—802 flight cycles after the effective date of this AD.
ESNs 51146, 51177, 51145, and 51149—380 flight cycles after the effective date of this AD.
Blades shown in RR ASB No. RB.211–72–AG244, Revision 1 as fitted to ESNs 51001, 51137
and blade S/N RGG16694—1,680 flight cycles after the effective date of this AD.
ESN 51145, 51149, 51150 and 51204—796 flight cycles after the effective date of this AD.
ESN 51160—1,160 flight cycles after the effective date of this AD.
Blades shown in RR ASB No. ASB RB.211–72–AG244, Revision 1 as fitted to ESN 51193 and
blade S/N RGG20216—1,212 flight cycles after the effective date of this AD.
ESN 51200—1,237 flight cycles after the effective date of this AD.
ESN 51280—1,551 flight cycles after the effective date of this AD.
Blades shown in RR ASB No. RB.211–72–AG244, Revision 1 as fitted to ESN 51004, ‘‘na’’ and
blade S/Ns RGG12590, RGG14081, and RGG15419—3,433 flight cycles after the effective
date of this AD.
ESN 51156—1,627 flight cycles after the effective date of this AD.
Blades shown in RR ASB No. RB.211–72–AG244, Revision 1 as fitted to ESN 51175, 51194,
51201, 51205, and 51228—2,042 flight cycles after the effective date of this AD.
ESN 51264—4,309 flight cycles after the effective date of this AD.
ESN 51443—2,636 flight cycles after the effective date of this AD.
Blade S/N RGG15698—2,638 flight cycles after the effective date of this AD.
Issued in Burlington, Massachusetts, on
January 10, 2011.
Peter A. White,
Acting Manager, Engine and Propeller
Directorate, Aircraft Certification Service.
[FR Doc. 2011–775 Filed 1–13–11; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2010–1301; Directorate
Identifier 2010–SW–008–AD]
(f) This AD differs from MCAI European
Aviation safety Agency (EASA) AD 2010–
0097, dated May 26, 2010. The EASA AD
uses calendar dates for initial inspection
thresholds. This AD uses flight cycles.
RIN 2120–AA64
Alternative Methods of Compliance
AGENCY:
Airworthiness Directives; MD
Helicopters, Inc. (MDHI) Model MD900
Helicopters
Federal Aviation
Administration, DOT.
ACTION: Notice of proposed rulemaking
(NPRM).
(g) The Manager, Engine Certification
Office, FAA, has the authority to approve
AMOCs for this AD, if requested using the
procedures found in 14 CFR 39.19.
mstockstill on DSKH9S0YB1PROD with PROPOSALS
(h) Refer to EASA AD 2010–0097, dated
May 26, 2010, and RR Alert SB No. RB.211–
72–AG244, Revision 1, dated January 26,
2010, for related information. Contact RollsRoyce plc, P.O. Box 31, DERBY, DE24 8BJ,
UK; telephone 44 (0) 1332 242424; fax 44 (0)
1332 249936, for a copy of this service
information.
(i) Contact Alan Strom, Aerospace
Engineer, Engine Certification Office, FAA,
Engine & Propeller Directorate, 12 New
England Executive Park, Burlington, MA
01803; e-mail: alan.strom@faa.gov; telephone
(781) 238–7143; fax (781) 238–7199.
VerDate Mar<15>2010
16:43 Jan 13, 2011
Jkt 223001
This document proposes
superseding an existing airworthiness
directive (AD) for MDHI Model MD900
helicopters. That AD currently requires
turning on both Vertical Stabilizer
Control System (VSCS) switches and
turning off the autopilot (AP/SAS)
switch; pulling certain AP/SAS circuit
breakers; installing a placard near the
AP/SAS master switch; installing an
airspeed limitation placard on the
instrument panel; and making changes
to the Rotorcraft Flight Manual (RFM).
This action would retain those
requirements and would provide an
SUMMARY:
Related Information
PO 00000
Frm 00003
Fmt 4702
Sfmt 4702
option of replacing each affected tube
adapter with a newly-designed tube
adapter, which would provide
terminating action for the unsafe
condition. This proposal is prompted by
the manufacturer introducing an
improved, newly-designed tube adapter.
The actions specified by this AD are
intended to prevent loss of yaw control
and subsequent loss of control of the
helicopter.
DATES: Comments must be received on
or before March 15, 2011.
ADDRESSES: Use one of the following
addresses to submit comments on this
proposed AD:
• Federal eRulemaking Portal: Go to
https://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.
You may get the service information
identified in this proposed AD from MD
Helicopters, Inc., Attn: Customer
Support Division, 4555 E. McDowell
Rd., Mail Stop M615, Mesa, AZ 85215–
9734, telephone 1–800–388–3378, fax
480–346–6813, or at https://
www.mdhelicopters.com.
You may examine the comments to
this proposed AD in the AD docket on
E:\FR\FM\14JAP1.SGM
14JAP1
Agencies
[Federal Register Volume 76, Number 10 (Friday, January 14, 2011)]
[Proposed Rules]
[Pages 2605-2607]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-775]
========================================================================
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. 76, No. 10 / Friday, January 14, 2011 /
Proposed Rules
[[Page 2605]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2010-0821; Directorate Identifier 2010-NE-30-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: We propose to adopt a new airworthiness directive (AD) for the
products listed above. This proposed AD results from mandatory
continuing airworthiness information (MCAI) issued by an aviation
authority of another country to identify and correct an unsafe
condition on an aviation product. The MCAI describes the unsafe
condition as:
In January 2009 a Trent 895 powered Boeing 777-200 aircraft
experienced release of a low pressure (LP) compressor blade which
failed due to fatigue cracking in the root section of the blade. The
released blade (undercut root standard) had received a part life
processing to apply a compression layer to the blade root (Service
Bulletin SB 72-D672--Introduction of Laser Shock Peening (LSP)) and
also a part life upgrade to the retention feature lubrication
system. Investigation has revealed that the effectiveness of this
upgraded blade root lubrication coating system may be reduced
dependant on the extent of previous running with the earlier
standard, leading to increased blade root stress levels. In the
specific case of the released blade, a review of its in-service
modification history has shown that it operated for a relatively
high number of flight cycles prior to the compression layer
processing and the new retention feature lubrication system. A
review of the Engine Health Monitoring data has also identified it
operated at high N1 speeds compared to the Trent 800 fleet average
N1 speeds. The combination of these factors has resulted in
increased fatigue life usage which is considered to have led to
crack initiation and propagation prior to reaching the blades
declared life limit. A review of all in-service undercut/LSP
standard Trent 800 LP compressor blades has identified specific
blades that carry a similar increased susceptibility to cracking.
This AD is issued to mitigate the risk of possible multiple fan
blades failure affecting those blades identified as described above
which could lead to high energy non contained debris from the
engine.
We are proposing this AD to prevent LP compressor blades from failing
due to blade root cracks, which could lead to uncontained engine
failure and damage to the airplane.
DATES: We must receive comments on this proposed AD by February 28,
2011.
ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Portal: Go to https://www.regulations.gov and follow the instructions for sending your
comments electronically.
Mail: Docket Management Facility, U.S. Department of
Transportation, 1200 New Jersey Avenue, SE., West Building Ground
Floor, Room W12-140, Washington, DC 20590-0001.
Hand Delivery: Deliver to Mail address above between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
Fax: (202) 493-2251.
Contact Rolls-Royce plc, P.O. Box 31, DERBY, DE24 8BJ, UK;
telephone 44 (0) 1332 242424; fax 44 (0) 1332 249936, for the service
information identified in this proposed AD.
Examining the AD Docket
You may examine the AD docket on the Internet at https://www.regulations.gov; or in person at the Docket Operations office
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 Operations office (phone (800) 647-5527) is the
same as the Mail address provided in the ADDRESSES section. Comments
will be available in the AD docket shortly after receipt.
FOR FURTHER INFORMATION CONTACT: Alan Strom, Aerospace Engineer, Engine
Certification Office, FAA, Engine & Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803; e-mail:
alan.strom@faa.gov; telephone (781) 238-7143; fax (781) 238-7199.
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-2010-0821;
Directorate Identifier 2010-NE-30-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 https://www.regulations.gov, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact
with FAA personnel concerning this proposed AD. Using the search
function of the Web site, anyone can find and read the comments in any
of our dockets, including, if provided, the name of the individual who
sent the comment (or signed the comment on behalf of an association,
business, labor union, etc.). You may review the DOT's complete Privacy
Act Statement in the Federal Register published on April 11, 2000 (65
FR 19477-78).
Discussion
The European Aviation Safety Agency (EASA), which is the Technical
Agent for the Member States of the European Community, has issued EASA
Airworthiness Directive 2010-0097, dated May 26, 2010 (referred to
after this as ``the MCAI''), to correct an unsafe condition for the
specified products. The MCAI states:
In January 2009 a Trent 895 powered Boeing 777-200 aircraft
experienced release of a low pressure (LP) compressor blade which
failed due to fatigue cracking in the root section of the blade. The
released blade (undercut root standard) had received a part life
processing to apply a compression layer to the blade root (Service
Bulletin SB 72-D672--Introduction of Laser Shock Peening (LSP)) and
also a part life upgrade to the retention feature lubrication
system. Investigation has revealed that the effectiveness of this
upgraded blade root lubrication coating system may be reduced
dependant on the extent of previous running with the earlier
standard, leading to
[[Page 2606]]
increased blade root stress levels. In the specific case of the
released blade, a review of its in-service modification history has
shown that it operated for a relatively high number of flight cycles
prior to the compression layer processing and the new retention
feature lubrication system. A review of the Engine Health Monitoring
data has also identified it operated at high N1 speeds compared to
the Trent 800 fleet average N1 speeds. The combination of these
factors has resulted in increased fatigue life usage which is
considered to have led to crack initiation and propagation prior to
reaching the blades declared life limit. A review of all in-service
undercut/LSP standard Trent 800 LP compressor blades has identified
specific blades that carry a similar increased susceptibility to
cracking.
This AD is issued to mitigate the risk of possible multiple fan
blades failure affecting those blades identified as described above
which could lead to high energy non contained debris from the
engine.
You may obtain further information by examining the MCAI in the AD
docket.
Relevant Service Information
Rolls-Royce plc has issued Alert Service Bulletin No. RB.211-72-
AG244, Revision 1, dated January 26, 2010. The actions described in
this service information are intended to correct the unsafe condition
identified in the MCAI.
FAA's Determination and Requirements of This Proposed AD
This product has been approved by the aviation authority of the
United Kingdom, and is approved for operation in the United States.
Pursuant to our bilateral agreement with the United Kingdom, they have
notified us of the unsafe condition described in the MCAI and service
information referenced above. We are proposing this AD because we
evaluated all information provided by EASA, and determined the unsafe
condition exists and is likely to exist or develop on other products of
the same type design.
Costs of Compliance
Based on the service information, we estimate that this proposed AD
would affect about 20 engines installed on airplanes of U.S. registry.
We also estimate that it would take about 18 work-hours per engine to
perform the inspections in one year's time. The average labor rate is
$85 per work-hour. We estimate that one LP compressor blade per year
would need replacement, at a cost of about $82,000. Based on these
figures, we estimate the annual cost of the proposed AD on U.S.
operators to be $112,600. Our cost estimate is exclusive of possible
warranty coverage.
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 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); 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 regulatory evaluation of the estimated costs to
comply with this proposed AD and placed it in the AD docket.
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 adding the following new AD:
Rolls-Royce plc: Docket No. FAA-2010-0821; Directorate Identifier
2010-NE-30-AD.
Comments Due Date
(a) We must receive comments by February 28, 2011.
Affected Airworthiness Directives (ADs)
(b) None.
Applicability
(c) This AD applies to Rolls-Royce plc (RR) RB211-Trent 875-17,
RB211-Trent 877-17, RB211-Trent 884-17, RB211-Trent 884B-17, RB211-
Trent 892-17, RB211-Trent 892B-17, and RB211-Trent 895-17 turbofan
engines.
Reason
(d) This AD results from mandatory continuing airworthiness
information (MCAI) issued by an aviation authority of another
country to identify and correct an unsafe condition on an aviation
product. We are issuing this AD to prevent low-pressure (LP)
compressor blades from failing due to blade root cracks, which could
lead to uncontained engine failure and damage to the airplane.
Actions and Compliance
(e) Unless already done, do the following actions.
(1) Using the corresponding compliance threshold in Table 1 of
this AD, perform an initial ultrasonic inspection (UI) of the
affected LP compressor blades identified by serial number (S/N) in
Appendices 3A through 3F of RR Alert Service Bulletin (ASB) No.
RB.211-72-AG244, Revision 1, dated January 26, 2010.
Table 1--Initial Inspection Thresholds
----------------------------------------------------------------------------------------------------------------
Appendix number of RR ASB No. RB.211-72-AG244, Revision 1, that
identifies affected LP compressor blades by S/N Initial inspection threshold
----------------------------------------------------------------------------------------------------------------
3A.................................................................. 120 flight cycles after the effective date
of this AD.
[[Page 2607]]
3B.................................................................. Blades shown in RR ASB No. RB.211-72-
AG244, Revision 1 as fitted to engine
serial number (ESN) 51039--802 flight
cycles after the effective date of this
AD.
ESNs 51146, 51177, 51145, and 51149--380
flight cycles after the effective date of
this AD.
3C.................................................................. Blades shown in RR ASB No. RB.211-72-
AG244, Revision 1 as fitted to ESNs
51001, 51137 and blade S/N RGG16694--
1,680 flight cycles after the effective
date of this AD.
ESN 51145, 51149, 51150 and 51204--796
flight cycles after the effective date of
this AD.
ESN 51160--1,160 flight cycles after the
effective date of this AD.
3D.................................................................. Blades shown in RR ASB No. ASB RB.211-72-
AG244, Revision 1 as fitted to ESN 51193
and blade S/N RGG20216--1,212 flight
cycles after the effective date of this
AD.
ESN 51200--1,237 flight cycles after the
effective date of this AD.
ESN 51280--1,551 flight cycles after the
effective date of this AD.
3E.................................................................. Blades shown in RR ASB No. RB.211-72-
AG244, Revision 1 as fitted to ESN 51004,
``na'' and blade S/Ns RGG12590, RGG14081,
and RGG15419--3,433 flight cycles after
the effective date of this AD.
ESN 51156--1,627 flight cycles after the
effective date of this AD.
3F.................................................................. Blades shown in RR ASB No. RB.211-72-
AG244, Revision 1 as fitted to ESN 51175,
51194, 51201, 51205, and 51228--2,042
flight cycles after the effective date of
this AD.
ESN 51264--4,309 flight cycles after the
effective date of this AD.
ESN 51443--2,636 flight cycles after the
effective date of this AD.
Blade S/N RGG15698--2,638 flight cycles
after the effective date of this AD.
----------------------------------------------------------------------------------------------------------------
(2) Thereafter, perform repetitive UIs of the affected LP
compressor blades within every 100 flight cycles.
(3) Use paragraph 3 of Accomplishment Instructions of RR ASB No.
RB.211-72-AG244, Revision 1, dated January 26, 2010, and Appendix 1
of that ASB to perform the UIs.
(4) Remove blades from service before further flight that fail
the inspection criteria in Appendix 1 of RR ASB No. RB.211-72-AG244,
Revision 1, dated January 26, 2010.
(5) After the effective date of this AD, do not install any
affected LP compressor blade unless it has passed the initial and
repetitive UIs required by this AD.
FAA AD Differences
(f) This AD differs from MCAI European Aviation safety Agency
(EASA) AD 2010-0097, dated May 26, 2010. The EASA AD uses calendar
dates for initial inspection thresholds. This AD uses flight cycles.
Alternative Methods of Compliance
(g) The Manager, Engine Certification Office, FAA, has the
authority to approve AMOCs for this AD, if requested using the
procedures found in 14 CFR 39.19.
Related Information
(h) Refer to EASA AD 2010-0097, dated May 26, 2010, and RR Alert
SB No. RB.211-72-AG244, Revision 1, dated January 26, 2010, for
related information. Contact Rolls-Royce plc, P.O. Box 31, DERBY,
DE24 8BJ, UK; telephone 44 (0) 1332 242424; fax 44 (0) 1332 249936,
for a copy of this service information.
(i) Contact Alan Strom, Aerospace Engineer, Engine Certification
Office, FAA, Engine & Propeller Directorate, 12 New England
Executive Park, Burlington, MA 01803; e-mail: alan.strom@faa.gov;
telephone (781) 238-7143; fax (781) 238-7199.
Issued in Burlington, Massachusetts, on January 10, 2011.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 2011-775 Filed 1-13-11; 8:45 am]
BILLING CODE 4910-13-P