

[Federal Register: October 15, 2007 (Volume 72, Number 198)]
[Proposed Rules]               
[Page 58267-58268]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr15oc07-11]                         


[[Page 58267]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28059; Directorate Identifier 2007-NE-13-AD]
RIN 2120-AA64

 
Airworthiness Directives; Rolls-Royce plc (RR) RB211 Trent 500, 
700, and 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) provided by the aviation 
authority of the United Kingdom to identify and correct an unsafe 
condition on an aviation product. The MCAI states the following:

    This action is necessary following the discovery of IP 
Compressor Rotor rear balance land cracking on an in-service Trent 
800 engine. Stress analysis of the damaged rotor has shown a 
possible threat to the rotor integrity, the cracking therefore 
presents a potential unsafe condition.

    We are proposing this AD to detect cracking on the intermediate 
pressure (IP) Compressor rotor rear balance land. IP compressor rotor 
rear balance land cracking can lead to uncontained failure of the rotor 
and damage to the airplane.

DATES: We must receive comments on this proposed AD by November 14, 
2007.

ADDRESSES: You may send comments by any of the following methods:
     Government-wide rulemaking Web site: Go to http://www.regulations.gov
 and follow the instructions for sending your 

comments electronically.
     Mail: U.S. Department of Transportation, Docket 
Operations, West Building Ground Floor, Room W12-140, 1200 New Jersey 
Avenue, SE., Washington, DC 20590.
     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://dms.dot.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: Christopher Spinney, Aerospace 
Engineer, Engine Certification Office, FAA, Engine & Propeller 
Directorate, 12 New England Executive Park, Burlington, MA 01803; e-
mail: christopher.spinney@faa.gov; telephone (781) 238-7175; 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-2007-
28059; Directorate Identifier 2007-NE-13-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://dms.dot.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

    The European Aviation Safety Agency (EASA), which is the Technical 
Agent for the Member States of the European Community, has issued EASA 
Airworthiness Directive 2007-0052, dated February 23, 2007 to correct 
an unsafe condition for the specified products. The EASA AD states:

    This Airworthiness Directive requires inspections for cracks in 
the rear balance land of the IP Compressor Rotor. The inspections 
comprise an on-wing one-off inspection by borescope for RR Trent 800 
engines which must be completed within a short timescale, and in-
shop inspections to be completed at each opportunity for RR Trent 
500, 700 and 800 engines (the in-shop inspection may be carried out 
in lieu of the on-wing inspection for the Trent 800 engines if it is 
accomplished within the timescale applicable to the on-wing 
inspection). This action is necessary following the discovery of IP 
Compressor Rotor rear balance land cracking on an in-service Trent 
800 engine. Stress analysis of the damaged rotor has shown a 
possible threat to the rotor integrity, the cracking therefore 
presents a potential unsafe condition. The cause of the cracking is 
currently not fully understood but evidence suggests it relates to 
an unusual balance weight condition.

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

Relevant Service Information

    RR has issued Alert Service Bulletin (ASB) RB.211-72-AF313, dated 
February 22, 2007 and ASB RB.211-72-AF260, Revision 1, dated January 
17, 2007. The actions described in this service information are 
intended to correct the unsafe condition identified in the EASA AD.

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 EASA AD 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. This proposed AD would require inspecting the IP 
Compressor rotor rear balance land for cracks.

Costs of Compliance

    We estimate that this proposed AD would affect about 110 engines 
installed on airplanes of U.S. registry. We also estimate that it would 
take about 3.5 work-hours per engine to perform the proposed actions 
and that the average labor rate is $80 per work-hour. Based on these 
figures, we estimate the total cost of the proposed AD to U.S. 
operators to be $30,800. 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

[[Page 58268]]

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-2007-28059; Directorate Identifier 
2007-NE-13-AD.

Comments Due Date

    (a) We must receive comments by November 14, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Rolls-Royce plc RB211 Trent 553-61, 
553A2-61, 556-61, 556A2-61, 556B-61, 560-61, 560A2-61, 768-60, 772-
60, 772B-60, 772C-60, 875-17, 877-17, 884-17, 884B-17, 892-17, 892B-
17, and 895-17 turbofan engines. These engines are installed on, but 
not limited to, Airbus A330, A340-500, A340-600, and Boeing 777 
series airplanes.

Reason

    (d) This action is necessary following the discovery of IP 
Compressor Rotor rear balance land cracking on an in-service Trent 
800 engine. Stress analysis of the damaged rotor has shown a 
possible threat to the rotor integrity, the cracking therefore 
presents a potential unsafe condition. The proposed AD would require 
actions that are intended to address the unsafe condition described 
in the MCAI.
    We are proposing this AD to detect cracking on the intermediate 
pressure (IP) Compressor rotor rear balance land. IP compressor 
rotor rear balance land cracking can lead to uncontained failure of 
the rotor and damage to the airplane.

Actions and Compliance

    (e) Unless already done, do the following actions:

Inspection--On-Wing

    (1) Applicable to RR Trent 800 engines not previously inspected 
per Rolls-Royce RB211 Propulsion System Alert Non Modification 
Service Bulletin RB.211-72-AF260, Revision 1, dated January 17, 2007 
or original issue, dated October17, 2006: Within 400 flight cycles 
of the Effective Date of this AD inspect the IP Compressor rotor 
rear balance land for cracks in accordance with Rolls-Royce RB211 
Propulsion System Alert Non Modification Service Bulletin RB.211-72-
AF313, dated February 22, 2007 section 3 Accomplishment 
Instructions. Engines on which cracking is found should be rejected 
from service.

Inspection--In-Shop

    (2) Applicable to RR Trent 500, 700 and 800 engines at each shop 
visit in which the engine is sufficiently disassembled to access the 
IP Compressor Module rear face: Inspect the IP Compressor rotor rear 
balance land for cracks in accordance with Rolls-Royce RB211 
Propulsion System Alert Non Modification Service Bulletin RB.211-72-
AF260, Revision 1, dated January 17, 2007, or original issue section 
3 Accomplishment Instructions.

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 EASA Airworthiness Directive 2007-0052, dated 
February 23, 2007, and Rolls-Royce plc Alert Service Bulletin (ASB) 
RB.211-72-AF313, dated February 22, 2007, and ASB RB.211-72-AF260, 
Revision 1, dated January 17, 2007, for related information.
    (h) Contact Christopher Spinney, Aerospace Engineer, Engine 
Certification Office, FAA, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
christopher.spinney@faa.gov; telephone (781) 238-7175; fax (781) 

238-7199, for more information about this AD.

    Issued in Burlington, Massachusetts, on October 9, 2007.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. E7-20242 Filed 10-12-07; 8:45 am]

BILLING CODE 4910-13-P
