
[Federal Register: April 7, 2010 (Volume 75, Number 66)]
[Proposed Rules]               
[Page 17630-17632]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07ap10-16]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0364; Directorate Identifier 2009-NE-27-AD]
RIN 2120-AA64

 
Airworthiness Directives; Rolls-Royce plc RB211 Trent 700 and 
Trent 800 Series Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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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 completing a review of Engine Manual repair/acceptance 
limits for titanium compressor shafts, Rolls-Royce has found the 
specified limits to be incorrect such that the shot peened surface 
layer at life critical features (the axial dovetail slots) may have 
been inadvertently removed in-service. Removal of the shot peened layer 
results in increased vulnerability of the part to tensile stresses, 
which could reduce the life of the shaft to below the published life 
limits.
    We are proposing this AD to prevent failure of the intermediate-
pressure (IP) and high-pressure (HP) shaft, which could result in an 
overspeed condition, possible uncontained disc failure and damage to 
the airplane.

DATES: We must receive comments on this proposed AD by May 24, 2010.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://
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.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
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 (telephone (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: James Lawrence, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; e-mail: 
james.lawrence@faa.gov; telephone (781) 238-7176; 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-2010-0364; 
Directorate Identifier 2009-NE-27-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 
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.).

[[Page 17631]]

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 2009-0021 (Corrected February 9, 2009), dated 
February 6, 2009 (referred to after this as ``the MCAI''), to correct 
an unsafe condition for the specified products. The MCAI states:

    In completing a review of Engine Manual repair/acceptance limits 
for titanium compressor shafts, Rolls-Royce has found the specified 
limits to be incorrect such that the shot peened surface layer at 
life critical features (the axial dovetail slots) may have been 
inadvertently removed in-service. Removal of the shot peened layer 
results in increased vulnerability of the part to tensile stresses, 
which could reduce the life of the shaft to below the published life 
limits. The acceptable limits for material loss on these surfaces 
have now been corrected in the Engine Manual.
    This AD identifies shafts for which such dressing operations 
have been known to have been carried out and requires that an 
inspection for compliance with the corrected Engine Manual limits be 
accomplished and that the shafts be dispositioned accordingly.

You may obtain further information by examining the MCAI in the AD 
docket.

Relevant Service Information

    Rolls-Royce plc has issued Alert Service Bulletin RB.211-72-AG086, 
dated December 4, 2008. 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 12 products of U.S. registry. We also estimate that 
it would take about 8 work-hours per product to comply with this 
proposed AD. The average labor rate is $85 per work-hour. Required 
parts would cost about $15,000 per product. Based on these figures, we 
estimate the cost of the proposed AD on U.S. operators to be $188,160. 
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, 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-2010-0364; Directorate Identifier 
2009-NE-27-AD.

Comments Due Date

    (a) We must receive comments by May 24, 2010.

Affected Airworthiness Directives (ADs)

    (b) None.

Applicability

    (c) This AD applies to Rolls-Royce plc model (RR) RB211 Trent 
768-60, 772-60, 772B-60, 875-17, 877-17, 884-17, 884B-17, 892-17, 
892B-17, and 895-17 turbofan engines that have a compressor shaft 
listed by part number and serial number in Table 1 of this AD. These 
engines are installed on, but not limited to, Airbus A330 series and 
Boeing 777 series airplanes.

Reason

    (d) This AD results from a review of engine manual repair/
acceptance limits for titanium compressor shafts by RR. We are 
issuing this AD to prevent failure of the intermediate-pressure (IP) 
and high-pressure (HP) shaft, which could result in an overspeed 
condition, possible uncontained disc failure and damage to the 
airplane.

Actions and Compliance

    (e) Unless already done, do the following actions.
    (1) Perform a one-time, piece-part, full-focused inspection of 
the IP and HP compressor shafts listed by part number and serial 
number in Table 1 of this AD before exceeding the compliance period 
specified in Table 1 of this AD.
    (2) Guidance on full-focused inspections and acceptance limits 
can be found in the current, applicable RR engine manual.

[[Page 17632]]



                                        Table 1--List of Affected Shafts
----------------------------------------------------------------------------------------------------------------
                                                                                                    Compliance
                                                                                                      period
                                                                                                  (flight cycles
          Engine series             Affected component        Part No.         Shaft serial No.     in service
                                                                                                  after December
                                                                                                     4, 2008.)
----------------------------------------------------------------------------------------------------------------
Trent 800........................  1-8 IP Compressor    FK24100............  MW0115238..........             750
                                    Shaft.
Trent 800........................  1-4 HP Compressor    FK32580............  MW0115512..........             750
                                    Shaft.
Trent 800........................  1-4 HP Compressor    FK32580............  MW0004708..........            2000
                                    Shaft.
Trent 800........................  1-4 HP Compressor    FK32580............  MW00063868.........            2500
                                    Shaft.
Trent 800........................  1-8 IP Compressor    FK24100............  DN65507............            2500
                                    Shaft.
Trent 800........................  1-8 IP Compressor    FK24100............  DN65158............            2500
                                    Shaft.
Trent 800........................  1-4 HP Compressor    FK32580............  MW0125467..........            3500
                                    Shaft.
Trent 800........................  1-4 HP Compressor    FW11590............  DN65189............            3500
                                    Shaft.
Trent 800........................  1-8 IP Compressor    FK24100............  MW0091518..........            3500
                                    Shaft.
Trent 800........................  1-8 IP Compressor    FK24100............  MW0126365..........            3500
                                    Shaft.
Trent 800........................  1-8 IP Compressor    FK24100............  DN66422............            4750
                                    Shaft.
Trent 800........................  1-8 IP Compressor    FK24100............  MW0203314..........            4750
                                    Shaft.
Trent 700........................  1-8 IP Compressor    FK22279............  DN63228............            3250
                                    Shaft.
Trent 700........................  1-8 IP Compressor    FK26048............  MW0026046..........            4500
                                    Shaft.
----------------------------------------------------------------------------------------------------------------

Other FAA AD Provisions

    (f) Alternative Methods of Compliance (AMOCs): 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

    (g) Refer to MCAI EASA Airworthiness Directive 2009-0021 
(Corrected 09 February, 2009), dated February 6, 2009, for related 
information.
    (h) Contact James Lawrence, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
james.lawrence@faa.gov; telephone (781) 238-7176; fax (781) 238-
7199, for more information about this AD.

    Issued in Burlington, Massachusetts, on March 31, 2010.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2010-7830 Filed 4-6-10; 8:45 am]
BILLING CODE 4910-13-P

