[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