Document ID: FAA-2012-0482-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Rolls-Royce PLC Turbofan Engines
Posted Date: 2012-07-11T04:00Z

[Federal Register Volume 77, Number 133 (Wednesday, July 11, 2012)]
[Proposed Rules]
[Pages 40820-40822]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-16856]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0482; Directorate Identifier 2012-NE-14-AD]
RIN 2120-AA64

Airworthiness Directives; Rolls-Royce plc 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 all 
Rolls-Royce plc (RR) RB211-524G2-19; RB211-524G2-T-19; RB211-524G3-19; 
RB211-524G3-T-19; RB211-524H2-19; RB211-524H2-T-19; RB211-524H-36; 
RB211-524H-T-36; RB211-535E4-37; RB211-535E4-B-37; RB211-535E4-B-75; 
and RB211-535E4-C-37 turbofan engines. This proposed AD was prompted by 
an investigation by RR concluding that certain intermediate-pressure 
(IP) turbine discs produced before 1997 by a certain supplier may 
contain steel inclusions. This proposed AD would require removal of the 
affected IP turbine discs to inspect them for steel inclusions, and 
removal from service if the discs fail the inspection. This proposed AD 
would also require removal from service of some IP turbine discs at 
reduced life limits. We are proposing this AD to prevent uncontained IP 
turbine disc failure, engine failure, and damage to the airplane.

DATES: We must receive comments on this proposed AD by September 10, 
2012.

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.
    For service information identified in this proposed AD, contact 
Rolls-Royce plc, Corporate Communications, P.O. Box 31, Derby, England, 
DE248BJ; phone: 011-44-1332-242424; fax: 011-44-1332-245418 or email 
from http://www.rolls-royce.com/contact/civil_team.jsp, or download 
the publication from https://www.aeromanager.com. You may review copies 
of the referenced service information at the FAA, Engine & Propeller 
Directorate, 12 New England Executive Park, Burlington, MA. For 
information on the availability of this material at the FAA, call 781-
238-7125.

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 (phone: 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: Alan Strom, Aerospace Engineer, Engine 
Certification Office, FAA, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; phone: 781-238-7143; fax: 
781-238-7199; email: alan.strom@faa.gov.

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-2012-0482; 
Directorate Identifier 2012-NE-14-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.). 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 
AD 2012-0060, dated April 18, 2012 (referred to after this as ``the 
MCAI''), to correct an unsafe condition for the specified products. The 
MCAI states:

    The inspection of several intermediate pressure (IP) turbine 
discs at past engine overhauls identified the presence of steel 
inclusions in these parts. Further investigation concluded that all 
affected parts were manufactured from billets produced before 1997 
at a certain supplier who also melted steel in the same furnaces. 
Initial engineering evaluation concluded that the lives of the parts 
would not be affected by the presence of the said steel inclusions. 
This evaluation has been recently repeated, utilising improved 
structural analysis, and it is now concluded that the currently 
published lives of the components cannot be supported for some discs 
with a steel inclusion.

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

Relevant Service Information

    RR has issued RB211-524G, 524H, and 535E4 Propulsion Systems Alert 
Service Bulletin No. RB.211-72-AG493, Revision 1, dated November 11, 
2011. The actions described in this service information are intended to 
confirm the presence or absence of steel inclusions on the affected IP 
turbine discs, and to require removal of certain discs at new lower 
life limits.

FAA's Determination and Requirements of This Proposed AD

    This product has been approved by the United Kingdom and is 
approved for operation in the United States. Pursuant to our bilateral 
agreement with the European Community, EASA has 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

[[Page 40821]]

and is likely to exist or develop on other products of the same type 
design.
    This proposed AD would require removal of the affected IP turbine 
discs to inspect them for steel inclusions, and if found, this AD would 
require removal from service. This proposed AD would also impose a new 
lower life limit on affected IP turbine discs.

Costs of Compliance

    We estimate that this proposed AD would affect about 200 engines 
installed on airplanes of U.S. registry. We also estimate that it would 
take about 12.5 work-hours per engine to inspect an IP turbine disc. 
The average labor rate is $85 per work-hour. In addition, 77 discs must 
be removed earlier than the existing Airworthiness Limitation Section 
requires. A prorated replacement IP turbine disc would cost about 
$9,925 per engine. We also estimate the cost of replacing a disc if it 
fails the inspection would be $225,000. Based on these figures, we 
estimate the cost of the proposed AD on U.S. operators to be $976,725.

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, Incorporation by 
reference, 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 
airworthiness directive (AD):

Rolls-Royce plc: Docket No. FAA-2012-0482; Directorate Identifier 
2012-NE-14-AD.

(a) Comments Due Date

    We must receive comments by September 10, 2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all Rolls-Royce plc (RR) RB211-524G2-19; 
RB211-524G2-T-19; RB211-524G3-19; RB211-524G3-T-19; RB211-524H2-19; 
RB211-524H2-T-19; RB211-524H-36; RB211-524H-T-36; RB211-535E4-37; 
RB211-535E4-B-37; RB211-535E4-B-75; and RB211-535E4-C-37 turbofan 
engines.

(d) Reason

    This AD was prompted by an investigation by RR concluding that 
certain intermediate-pressure (IP) turbine discs produced before 
1997 by a certain supplier may contain steel inclusions. We are 
issuing this AD to prevent uncontained IP turbine disc failure, 
engine failure, and damage to the airplane.

(e) Actions and Compliance

    Unless already done, do the following actions.

(f) Disc Inspection

    After the effective date of this AD, use Appendix 1 and Appendix 
2 of RR RB211-524G, 524H, and 535E4 Propulsion Systems Alert Service 
Bulletin (ASB) No. RB.211-72-AG493, Revision 1, dated November 11, 
2011; to determine if the IP turbine disc is below or above the 
inspection threshold.
    (1) If below the inspection threshold then clean, demagnetize, 
and perform a Superconductive Quantitative Inductive Device (SQUID) 
inspection of the disc at the next shop visit or before the disc 
reaches the inspection threshold, whichever is later. Use Appendix 4 
of RR RB211-524G, 524H, and 535E4 Propulsion Systems ASB No. RB.211-
72-AG493, Revision 1, dated November 11, 2011, to perform the SQUID 
inspection.
    (2) If above the inspection threshold, clean, demagnetize and 
perform a SQUID inspection of the disc if in the shop or, at the 
next shop visit, whichever occurs first. Use Appendix 4 of RR RB211-
524G, 524H, and 535E4 Propulsion Systems ASB No. RB.211-72-AG493, 
Revision 1, dated November 11, 2011, to perform the SQUID 
inspection.
    (3) Do not return to service any disc that fails the inspection 
required by this AD.

(g) Disc Life Reduction

    (1) After the effective date of this AD, use Appendix 2 of RR 
RB211-524G, 524H, and 535E4 Propulsion Systems ASB No. RB.211-72-
AG493, Revision 1, dated November 11, 2011, to determine the new 
lower life of affected IP turbine disc(s).
    (2) Remove from service any disc at the next shop visit or 
before it exceeds its new lower life limit, whichever is later, as 
found in Appendix 2 of RR RB211-524G, 524H, and 535E4 Propulsion 
Systems ASB No. RB.211-72-AG493, Revision 1, dated November 11, 
2011.
    (3) Do not return to service any disc that exceeds its new lower 
life limit, as found in Appendix 2 of RR RB211-524G, 524H, and 535E4 
Propulsion Systems ASB No. RB.211-72-AG493, Revision 1, dated 
November 11, 2011.

(h) Definition of Shop Visit

    For purposes of this AD, a shop visit is defined as induction 
into the shop where the IP and low pressure (LP) turbine module is 
removed from the engine, and any casing is removed from the IP and 
LP turbine module.

(i) Alternative Methods of Compliance (AMOCs)

    The Manager, Engine Certification Office, may approve AMOCs for 
this AD. Use the procedures found in 14 CFR 39.19 to make your 
request.

(j) Related Information

    (1) For more information about this AD, contact Alan Strom, 
Aerospace Engineer, Engine Certification Office, FAA, Engine & 
Propeller Directorate, 12 New England Executive Park, Burlington, MA 
01803; phone: 781-238-7143; fax: 781-238-7199; email: 
alan.strom@faa.gov.
    (2) European Aviation Safety Agency AD 2012-0060, dated April 
18, 2012, and Rolls-Royce plc RB211-524G, 524H, and 535E4 Propulsion 
Systems ASB No. RB.211-72-AG493, Revision 1, dated November 11, 
2011, pertain to the subject of this AD.
    (3) For service information identified in this AD, contact 
Rolls-Royce plc, Corporate Communications, P.O. Box 31, Derby,

[[Page 40822]]

England, DE248BJ; phone: 011-44-1332-242424; fax: 011-44-1332-245418 
or email from http://www.rolls-royce.com/contact/civil_team.jsp, or 
download the publication from https://www.aeromanager.com. You may 
review copies of the referenced service information at the FAA, 
Engine & Propeller Directorate, 12 New England Executive Park, 
Burlington, MA. For information on the availability of this material 
at the FAA, call 781-238-7125.

    Issued in Burlington, Massachusetts, on June 25, 2012.
Peter A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-16856 Filed 7-10-12; 8:45 am]
BILLING CODE 4910-13-P