[Federal Register Volume 72, Number 180 (Tuesday, September 18, 2007)]
[Rules and Regulations]
[Pages 53108-53110]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-18324]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-27955; Directorate Identifier 2007-NE-15-AD; 
Amendment 39-15201; AD 2007-19-10]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce plc RB211 Trent 500 Series 
Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule; request for comments.

-----------------------------------------------------------------------

SUMMARY: We are adopting a new airworthiness directive (AD) for the 
products listed above. This AD results from mandatory continuing 
airworthiness information (MCAI) provided by an aviation authority of 
the United Kingdom (UK) to identify and correct an unsafe condition on 
Rolls-Royce plc RB211 Trent 500 series turbofan engines. The MCAI 
states the following:

    This AD requires replacement of Intermediate Pressure Compressor 
(IP Compressor) Drums (Part Number FK30102) of nine part serial 
numbers. This action is necessary following the discovery of strain 
induced porosity in a Trent 500 IP Compressor Drum forging. 
Engineering assessment concluded that the problem is caused by the 
forging process and it is

[[Page 53109]]

believed that this is a batch related occurrence. Nine discs, 
identified as coming from the same batch, could be affected by this 
problem. Strain induced porosity in the dovetail posts of the stage 
1 of the IP Compressor drum could result, in the worst case, in an 
uncontained loss of 2 IP Compressor stage 1 blades. Thus, the strain 
induced porosity possibly affecting those nine discs presents a 
potential unsafe condition.

    We are issuing this AD to prevent uncontained loss of IP compressor 
stage 1 blades.

DATES: This AD becomes effective October 3, 2007. We must receive 
comments on this AD by October 3, 2007.

ADDRESSES: You may send comments by any of the following methods:
     DOT Docket Web Site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, 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.
     Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the instructions for submitting comments.

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 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 and Propeller 
Directorate, 12 New England Executive Park, Burlington, MA 01803; e-
mail: [email protected], telephone (781) 238-7175, fax (781) 
238-7199.

SUPPLEMENTARY INFORMATION: 

Discussion

    The European Aviation Safety Agency (EASA), which is the Technical 
Agent for the Member States of the European Union, has issued AD 2007-
0046, dated February 22, 2007, to correct an unsafe condition for the 
specified products. The EASA AD states:

    This Airworthiness Directive requires replacement of 
Intermediate Pressure Compressor (IP Compressor) Drums (Part Number 
FK30102) of nine part serial numbers. This action is necessary 
following the discovery of strain induced porosity in a Trent 500 IP 
Compressor Drum forging. Engineering assessment concluded that the 
problem is caused by the forging process and it is believed that 
this is a batch related occurrence. Nine discs, identified as coming 
from the same batch, could be affected by this problem. Strain 
induced porosity in the dovetail posts of the stage 1 of the IP 
Compressor drum could result, in the worst case, in an uncontained 
loss of 2 IP Compressor stage 1 blades. Thus, the strain induced 
porosity possibly affecting those nine discs presents a potential 
unsafe condition.

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

Relevant Service Information

    Rolls-Royce plc has issued Mandatory Service Bulletin No. 292 73 
2818, Original Issue, dated October 18, 2006, and Update No. 1, dated 
April 3, 2007. 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 AD

    This product has been approved by the aviation authority of the UK 
and is approved for operation in the United States. Pursuant to our 
bilateral agreement with the UK, they have notified us of the unsafe 
condition described in the EASA AD and service information referenced 
above. We are issuing this AD because we evaluated all the 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 AD requires removal of IP Compressor Drums, part number FK30102, 
serial numbers MW0134967, MW0131219, MW0156891, MW0158192, MW0164840, 
MW0168864, MW0168190, MW0171399, and KHI00012 from service at the next 
engine overhaul or before accumulating 2,190 cycles-since-new, 
whichever occurs first. This AD also requires replacement with a 
serviceable Drum.

FAA's Determination of the Effective Date

    An unsafe condition exists that requires the immediate adoption of 
this AD. The FAA has found that the risk to the flying public justifies 
waiving notice and comment prior to adoption of this rule because no 
airplanes that are registered in the United States use these engines. 
Therefore, we determined that notice and opportunity for public comment 
before issuing this AD are unnecessary and that good cause exists for 
making this amendment effective in fewer than 30 days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety, and we did not precede it by notice and opportunity for public 
comment. We invite you to send any written relevant data, views, or 
arguments about this AD. Send your comments to an address listed under 
the ADDRESSES section. Include ``Docket No. FAA-2007-27955; Directorate 
Identifier 2007-NE-15-AD'' at the beginning of your comments. We 
specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this AD. We will consider all 
comments received by the closing date and may amend this AD because of 
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 AD.

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 AD will not have federalism implications 
under Executive Order 13132. This AD will not have a substantial direct 
effect on the States, on the relationship between the national 
government and the States,

[[Page 53110]]

or on the distribution of power and responsibilities among the various 
levels of government.
    For the reasons discussed above, I certify this AD:
    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 AD and placed it in the AD docket.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new AD:

2007-19-10 Rolls-Royce plc: Amendment 39-15201; Docket No. FAA-2007-
27955; Directorate Identifier 2007-NE-15-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective October 
3, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Rolls-Royce plc RB211 Trent 553-61, 556-
61, 556B-61, 560-61, 553A2-61, 556A2-61, 556B2-61, and 560A2-61 
turbofan engines. These engines are installed on, but not limited 
to, Airbus A340-500 and 600 series airplanes.

Reason

    (d) European Aviation Safety Agency (EASA) AD No. 2007-0046, 
dated February 22, 2007, states:

This Airworthiness Directive requires replacement of Intermediate 
Pressure Compressor (IP Compressor) Drums (Part Number FK30102) of 
nine part serial numbers. This action is necessary following the 
discovery of strain induced porosity in a Trent 500 IP Compressor 
Drum forging. Engineering assessment concluded that the problem is 
caused by the forging process and it is believed that this is a 
batch related occurrence. Nine discs, identified as coming from the 
same batch, could be affected by this problem. Strain induced 
porosity in the dovetail posts of the stage 1 of the IP Compressor 
drum could result, in the worst case, in an uncontained loss of 2 IP 
Compressor stage 1 blades. Thus, the strain induced porosity 
possibly affecting those nine discs presents a potential unsafe 
condition.

Actions and Compliance

    (e) Unless already done, do the following actions.
    (1) Remove the IP Compressor Drums, part number FK30102, serial 
numbers MW0134967, MW0131219, MW0156891, MW0158192, MW0164840, 
MW0168864, MW0168190, MW0171399, and KHI00012, from service at the 
next engine overhaul or before accumulating 2,190 cycles-since-new, 
whichever occurs first.
    (2) Replace these IP Compressor Drums with a serviceable Drum.

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 AD 2007-0046, dated February 22, 2007, and 
Rolls-Royce plc Alert Service Bulletin No. RB.211-72-AF258, Revision 
1, dated March 29, 2007, for related information.
    (h) Contact Christopher Spinney, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
[email protected], telephone (781) 238-7175, fax (781) 
238-7199, for more information about this AD.

    Issued in Burlington, Massachusetts, on September 11, 2007.
Francis A. Favara,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. E7-18324 Filed 9-17-07; 8:45 am]
BILLING CODE 4910-13-P