[Federal Register Volume 70, Number 102 (Friday, May 27, 2005)]
[Proposed Rules]
[Pages 30653-30655]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-10635]


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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: [email protected].
    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.
----------------------------------------------------------------------------------------------------------------

    (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]
BILLING CODE 4910-13-P