[Federal Register: May 27, 2005 (Volume 70, Number 102)]
[Proposed Rules]
[Page 30653-30655]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr27my05-22]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2003-NE-38-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).
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SUMMARY: The FAA proposes to supersede an existing airworthiness
directive (AD) for Rolls-Royce plc (RR) models RB211 Trent 875-17,
Trent 877-17, Trent 884-17, Trent 884B-17, Trent 892-17, Trent 892B-17,
and Trent 895-17 turbofan engines with low pressure (LP) compressor fan
blades, part number (P/N) FW18548 installed. That AD currently requires
LP compressor fan blade replacement with new or previously reworked
blades, or rework of the existing LP compressor fan blades. This
proposed AD would require the same actions but at reduced compliance
times for certain airplane and engine rating combinations and certain
maximum gross weight limits. This proposed AD results from a number of
new production LP compressor blades found with surfaces formed outside
of design intent. We are proposing this AD to prevent possible multiple
uncontained LP compressor fan blade failure, due to cracking in the
blade root caused by increased stresses in the shear key slots.
DATES: We must receive any comments on this proposed AD by July 26,
2005.
ADDRESSES: Use one of the following addresses to comment on this
proposed AD:
By mail: Federal Aviation Administration (FAA), New
England Region, Office of the Regional Counsel, Attention: Rules Docket
No. 2003-NE-38-AD, 12 New England Executive Park, Burlington, MA 01803-
5299.
By fax: (781) 238-7055.
By e-mail: 9-ane-adcomment@faa.gov.
You can get the service information identified in this proposed AD
from
[[Page 30654]]
Rolls-Royce plc, PO Box 31, Derby, England, DE248BJ; telephone: 011-44-
1332-242424; fax: 011-44-1332-245418.
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 send 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-38-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.
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
On July 14, 2004, we issued AD 2004-15-02, Amendment 39-13736 (69
FR 44925, July 28, 2004). That AD requires LP compressor fan blade
replacement with new or previously reworked blades, or rework of the
existing LP compressor fan blades. The Civil Aviation Authority (CAA),
which is the airworthiness authority for the United Kingdom (U.K.),
notified the FAA that an unsafe condition may exist on Rolls-Royce plc
RB211 Trent 800 Series turbofan engines. The CAA advises that RR has
introduced revised rework lives for LP compressor fan blades, P/N
FW18548, in redefined airplane and engine rating combinations. These
rating combinations also take into account the airplane gross weight.
Relevant Service Information
We have reviewed and approved the technical contents of RR Service
Bulletin (SB) No. RB.211-72-E044, Revision 2, dated October 8, 2004,
that describes procedures for inspecting and reworking LP compressor
fan blades P/N FW18548, that utilize the shear key blade retention
device. The CAA classified this service bulletin as mandatory and
issued AD G-2004-0030, dated December 23, 2004, in order to ensure the
airworthiness of these RB211 Trent 800 series turbofan engines in the
U.K.
Bilateral Agreement Information
This engine model is manufactured in the U.K. 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. In keeping with this
bilateral airworthiness agreement, the CAA has kept the FAA informed of
the situation described above. We have 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.
FAA's Determination and Requirements of the Proposed AD
We have evaluated all pertinent information and identified an
unsafe condition that is likely to exist or develop on other products
of this same type design. Therefore, we are proposing this AD, which
would require at or before the accumulation of certain cycles-since-new
based on airplane and engine rating combinations and airplane gross
weight, replacement of LP compressor fan blades with new or previously
reworked LP compressor fan blades, or rework of the existing blades.
The proposed AD would require that you do these actions using the
service information described previously.
Costs of Compliance
About 392 RR RB211 Trent 800 series turbofan engines of the
affected design are in the worldwide fleet. We estimate that this
proposed AD would affect 106 engines installed on airplanes of U.S.
registry. We also estimate that about 100 work hours per engine are
needed to perform blade rework, and that the average labor rate is $65
per work hour. Based on these figures, we estimate the total cost of
the proposed AD to U.S. operators to be $689,000.
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 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 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-38-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:
[[Page 30655]]
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 Amendment 39-13736 (69 FR
44925, July 28, 2004) and by adding a new airworthiness directive, to
read as follows:
Rolls-Royce plc: Docket No. 2003-NE-38-AD.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive
comments on this airworthiness directive (AD) action by July 26,
2005.
Affected ADs
(b) This AD supersedes AD 2004-15-02, Amendment 39-13736.
Applicability
(c) This AD applies to Rolls-Royce plc (RR) models RB211 Trent
875-17, Trent 877-17, Trent 884-17, Trent 884B-17, Trent 892-17,
Trent 892B-17, and Trent 895-17 turbofan engines, with low pressure
(LP) compressor fan blades, part number FW18548 installed. These
engines are installed on, but not limited to, Boeing 777 series
airplanes.
Unsafe Condition
(d) This AD results from a number of new production LP
compressor blades found with surfaces formed outside of design
intent. We are issuing this AD to prevent possible multiple
uncontained LP compressor fan blade failure, due to cracking in the
blade root caused by increased stresses in the shear key slots.
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.
Actions Required for LP Compressor Fan Blades
(f) Replace LP compressor fan blades with new or previously
reworked LP compressor blades before accumulating the specified
cycles-since-new (CSN) in the following Table 1, or rework the
existing blades as specified in paragraph (g) of this AD.
Table 1.--LP Compressor Fan Blade Replacement or Rework Schedule
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Airplane maximum gross Replace or rework LP
Boeing 777 series weight (times 1,000 RB211 Trent engine compressor fan blades
pounds) model before accumulating
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-300............................... 660, 632.5............ -884, -892, -884B..... 2,400 CSN.
-200............................... 656................... -892, -895............ 2,400 CSN.
-200............................... 648................... -892, -892B........... 3,200 CSN.
-200............................... 632.5................. -892B................. 3,200 CSN.
-200............................... 632.5................. -892.................. 4,100 CSN.
-200............................... 555................... -884.................. 4,100 CSN.
-200............................... 545................... -877.................. 4,100 CSN.
-200............................... 535................... -875.................. 4,100 CSN.
-200............................... 506................... -875.................. 4,100 CSN.
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(g) Rework LP compressor fan blades at or before accumulating
the specified CSN in Table 1 of this AD. Follow paragraphs 3.B.(1)
through 3.B.(22) of Accomplishment Instructions of RR service
bulletin (SB) No. RB.211-72-E044, Revision 2, dated October 8, 2004,
to do the blade rework.
(h) For engines moved between configurations, calculate the
cycles remaining using either of the following:
(1) Subtract the total CSN from the most limiting
configuration's limit from Table 1 of this AD; or
(2) Calculate the cycles remaining using the following equation:
[GRAPHIC] [TIFF OMITTED] TP27MY05.000
Where:
Xr = Cycles remaining in current configuration.
Lc = Cyclic limit of current configuration from Table 1 of this AD.
Xn = Cycles accumulated in configuration n.
Ln = Cyclic limit in configuration n from Table 1 of this AD.
(i) Information on the source life of the cycle limits in Table
1 of this AD can be found in RR Alert SB No. RB.211-72-AE055,
Revision 3, dated May 28, 2004.
Alternative Methods of Compliance
(j) 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.
Related Information
(k) CAA airworthiness directive G-2004-030, dated December 23,
2004, and RR Alert SB No. RB.211-72-AE055, Revision 4, dated
December 9, 2004, pertain to the subject of this AD.
Issued in Burlington, Massachusetts, on May 23, 2005.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification
Service.
[FR Doc. 05-10635 Filed 5-26-05; 8:45 am]
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