DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA-2015-0095; Directorate Identifier 2015-NE-01-AD] RIN 2120-AA64 Airworthiness Directives; Rolls-Royce pic Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice ofproposed rulemaking (NPRM). [4910-13-P]

SUMMARY: We propose to adopt a new airworthiness directive (AD) for certain RollsRoyce pic (RR) RB211-524B-02, RB211-524B2-19, RB211-524B3-02, RB211-524B4- 02 , RB211-524B4-D-02 , RB211-524C2-19, RB211-524D4-19, RB211-524D4-39, and RB211-524D4X-19 turbofan engines. This proposed AD was prompted by several failures of affected high-pressure turbine (HPT) blades. This proposed AD would require removing affected HPT blades. We are proposing this AD to prevent failure of the HPT blade, which could lead to failure of one or more engines, loss of thrust control, and damage to the airplane. DATES: We must receive comments on this proposed AD by [INSERT DATE 60 DAYS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER]. ADDRESSES: You may send comments by any ofthe following methods:
• Federal eRulemaking Portal: Go to http: //www .regulations
.gov . Follow the instructions for submitting comments .• Mail: Docket Management Facility, U.S. Department of Transportation, 1200 New Jersey Avenue SE., West Building Ground Floor, Room W12-140 , Washington, DC 20590-000 1.

• 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 AD, contact Rolls-Royce plc, Corporate Communications, P.O. Box 31, Derby, England, DE248BJ; phone: 011-44-1332- 242424; fax: 011-44-1332-249936; email: http://www
.rollsroyce.com/contact/civil_team.jsp; Internet: https://www.aeromanager.com. You may view this 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 by searching for and locating Docket No. FAA-2015-0095; 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 mandatory continuing airworthiness information (MCAI), the regulatory evaluation, any comments received, and other information. The address for the Docket Office (phone: 800-647-5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt. FOR FURTHER INFORMATION CONTACT: Katheryn Malatek, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New 2England Executive Park, Burlington, MA 01803; phone: 781-238-7747 ; fax: 781-238- 7199; email: katheryn.malatek@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-2015-0095; Directorate Identifier 2015-NE-01-AD" at the beginning ofyour comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects ofthis 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. Discussion The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States ofthe European Community, has issued EASA AD 2014-0250, dated November 19 , 2014 (referred to hereinafter as " the MCAI"), to correct an unsafe condition for the specified products
. The MCAI states: There were a number of pre-MOD/SB 72-7730 High Pressure Turbine (HPT) blade failures, with some occurring within a relatively short time. Engineering analysis carried out by RR on those occurrences indicates that certain pre-MOD/SB 72-7730 blades, Part Number (PIN) UL32958 and 

### PIN UL21691 (hereafter 

### 3referred to as 'affected HPT blade') , with an accumulated life of 6500 flight hours (FH) since new or more, have an increased risk of in-service failure. This condition, ifnot corrected, could lead to HPT blade failure , release ofdebris and consequent (partial or complete) loss of engine power, possibly resulting in reduced control ofthe aeroplane
. You may obtain further information by examining the MCAI in the AD docket on the Internet at http: //www.regulations.gov by searching for and locating Docket No. FAA-2015-0095. 

### FAA's Determination and Requirements of This Proposed AD This product has been approved by the aviation authority ofthe United Kingdom, and is approved for operation in the United States. Pursuant to our bilateral agreement with the European Community, EASA has notified us ofthe 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 ofthe same type design. This proposed AD would require removal of affected HPT blades. Costs of 

### Compliance We estimate that this proposed AD affects 6 engines installed on airplanes ofU.S. registry
. We also estimate that it would take about 4 hours per engine to comply with this proposed AD. The average labor rate is $85 per hour
. Pro-rated cost of required parts is about $250 ,000 per engine
. Based on these figures , we estimate the cost ofthis proposed AD on U.S
. operators to be $1 ,502 ,040.

4Authority for This Rulemaking Title 49 ofthe United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority ofthe FAA Administrator.

" Subtitle VII: Aviation Programs ," describes in more detail the scope ofthe 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 ofthat 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 ofpower 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) ,

5(3) Will not affect intrastate aviation in Alaska to the extent that it justifies making a regulatory distinction, and (4) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria ofthe Regulatory Flexibility Act. 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. 

### § 39.13 [Amended) 2. The FAA amends § 39
. 13 by adding the following new airworthiness directive (AD): Rolls-Royce pic: Docket No. FAA-2015-0095; Directorate Identifier 2015-NE-01-AD
. (a) Comments Due Date We must receive comments by [INSERT DATE 60 DAYS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER]. (b) Affected ADs None
.

6(c) Applicability This AD applies to all Rolls-Royce plc (RR) RB211-524B-02 , RB211-524B2-19 , RB211-524B3-02 , RB211-524B4-02 , RB211-524B4-D-02 , RB211-524C2-19 , RB211- 524D4-19 , RB 2 11-5 24D4-39 , and RB211-524D4X-19 turbofan engines with highpressure turbine (HPT) blades , part numbers (PINs) UL32958 and UL21691 , installed. (d) Reason This AD was prompted by several failures of affected HPT blades. We are issuing this AD to prevent failure ofthe HPT blade , which could lead to failure of one or more engines , loss ofthrust control, and damage to the airplane. (e) Actions and Compliance Comply with this AD within the compliance times specified, unless already done. After the effective date ofthis AD , within 2 months or before exceeding 6, 500 flight hours since first installation ofHPT blades , 

### PINs UL32958 , and UL21691 , on an engine, whichever occurs later, remove all af fected HPT blades from service
. (f) Alternative Methods of Compliance (AMOCs) The Manager, Engine Certification Office, FAA, may approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 to make your request. You may email your request to : ANE-AD-AMOC @ faa
.gov. (g) Related Information (1) For more information about thi s AD, contact Katheryn Malatek, Aero space Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone : 7 81-238-7747 ; fax : 7 81

-238- 7 199; email: katheryn.malatek @ faa
.gov . 7(2) Refer to MCAI European Aviation Safety Agency AD 2014-0250, dated November 19 , 2014 , for more information. You may examine the MCAI in the AD docket on the Internet at http://www.regulations.gov by searching for and locating it in Docket No. FAA-2015-0095
.

Issued in Burlington, Massachusetts, on Apri l 22, 2015
.

Colleen M. D'Alessandro, Assistant Directorate Manager, Engine & Propeller Directorate, Aircraft Certification Service
.

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