[4910-13-P] DEPARTMENT OFTRANSPORTATION 

### FederalAviation Administration 14CFRPart39 [DocketNo. FAA-2012-0546; Directorate Identifier2012-NE-15-AD; Amendment 39-17253; AD 2012-22-16] R1N 2120-AA64 

### Airworthiness Directives; Pratt & 

### Whitney Division Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are adopting a new airworthiness directive (AD) for all Pratt & Whitney Division PW4050, PW4052, PW4056, PW4060, PW4060A, PW4060C, PW4062, PW4062A, PW4!52, PW4156, PW4156A, PW4158, PW4160, PW4460, PW4462, and PW4650 turbofan engines, including models with any dash number suffix. This AD was prompted by 16 reports ofdamaged or failed 3rd stage low-pressure turbine 

### (LPT) duct segments. This AD requires removing from service certain part numbers (PINs) of3rd stage LPT duct 

### segments. We are issuing this AD to prevent 

### failure ofthe 

### 3rd stage 

### LPT duct segments, which could lead to LPT rotor damage, uncontained engine failure, and damage to the airplane. DATES: This AD is effective [INSERT DATE 35 DAYS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER]. 

### ADDRESSES: For service information identified in this AD, contact Pratt & 

### Whitney, 400 Main St.,East Hartford, CT 06108; phone: 860-565-8770; fax: 860-565-4503. You 

### may review copies ofthe referenced service information at the FAA, Engine & 

### Propeller Directorate, 12 New England Executive Park, Burlington, MA. For information on the availability ofthis material at the FAA, call781-238-7125.Examining the AD Docket 

### You may examine the AD docket on the Internet at http://wwvv.regulations.gov;

or in person at the Docket Management Facility between 9 a.m. and 5p.m., Monday through Friday, exceptFederal holidays. The AD docket contains this AD, the regulatory 

### evaluation, any comments received, and other information. The address for the Docket Office (phone: 800-647-5527) is Document ManagementFacility, U.S. Department of 

### Transportation, Docket Operations, M-30, West Building Ground Floor, Room Wl2-140, 1200 NewJersey Avenue SE., Washington, DC 20590. FORFURTHER INFORMATION CONTACT: James Gray, Aerospace Engineer, 

### Engine & 

### Propeller Directorate, FAA, 12 New England Executive Park, Burlington, MA 01803; phone: 781-238-7742; fax: 781-238-7199; e-mail:james.e.gray@faa.gov. SUPPLEMENTARY INFORMATION: Discussion We issued a notice ofproposed rulemaking (NPRM) to amend 14 CFRpart 39 to include anADthat would apply to the specifiedproducts. ThatNPRMpublished in the Federal Register on July 11,2012 (77 FR40822). ThatNPRM proposedto require 

### removal from service of3rd stage LPT duct segments 

### PINs 50N095; 50N095-001; 50N235; 50N235-00I; 50N494-01; 50N494-001; 50N495-0i; and 50N495-001, atthe 

### next piece-part exposure afterthe effective date ofthe proposed AD. Comments 

### We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the proposal and the FAA's response to each comment. Agreement with the Proposed AD 

### One commenter, Boeing, agreed with the intent ofthe proposed AD.

2Request to Reference Pratt & Whitney Service Bulletin PW4ENG 72-488 One commenter, FedEx Express, requested that we add a reference to Pratt & Whitney Service BulletinPW4ENG 72-488 for a list ofthe engine serial nwnbers affected. We assume this request was made to add clarity. We do not agree. The AD applicability is for PW4000 engines with certain

### PIN 

### 3'' stage LPTduct segments installed. Althoughthe Pratt

### & Whitney Service Bulletin 

### does list engine serial numbers, it 

### is not necessary to include this information in the AD. We did not changethe AD. Conclusion 

### We reviewed the relevant data, considered the comments received, and determined that air safety and the public interestrequire adopting the AD as proposed. Costs ofCompliance We estimate thatthis AD 

### will affect !51 engines installed on airplanes ofU.S. registry. We estimatethat no additional labor costs will be incurredtoperform the required work as the work is done when the 3rd stage LPTduct segments are atpiece-part exposure. The average laborrate is $85 perwork-hour. Requiredparts will cost about $44,441 perengine. Based onthese figures, we estimate the total costofthe AD to U.S. operators will be $6,710,591. Authority for this Rulemaking Title 49 ofthe United States Code specifies the FAA's authorityto issuerules on aviation safety. Subtitle I, section 106, describes the authority ofthe FAA Administrator. Subtitle VII: Aviation Programs, describes inmore detail the scope ofthe Agency's authority. We are issuingthis rulemakingunderthe authority described in Subtitle VII, Part A, Subpart III, Section44701: "General requirements." Underthat section, Congress chargesthe FAA withpromoting safe flight ofcivil aircraft in air commerce by 

### 3prescribing regulations for practices, methods, andprocedures the Administratorfinds necessary for safety in aircommerce. This regulation is within the scope ofthat authority because it addresses an unsafe conditionthat is likely to exist or develop on products identified in this rulemaking action. Regulatory Findings This AD will nothave federalism implications under Executive Order 13132. This AD 

### will nothave a substantial direct effect onthe States, on the relationship betweenthe national government and the States, or onthe distribution ofpower and responsibilities amongthe various levels ofgovernment. Forthe reasons discussed above, I certifythatthis AD: (1) Is not a "significantregulatory action" under Executive Order 12866, (2) Is not a '"significantrule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), (3) Will not affect intrastate aviation in Alaska, and (4) Will nothave a significant economic impact, positive ornegative, on a substantial number ofsmall entities under the criteria ofthe Regulatory FlexibilityAct. 

### List ofSubjects in 14 CFRPart39 Air transportation, Aircraft, Aviation safety, Incorporationby reference, Safety. Adoption ofthe Amendment Accordingly, under the authority delegated to me bythe Administrator, the FAA amends 14 CFRpart 39 as follows: PART 39

- AIRWORTIDNESS DIRECTIVES 1. The authority citationfor part 39 continues to read as follows: Aulbority: 49 U.S.C. 106(g), 40113,44701.

4

### § 39.13 [Amended] 2. TheFAA amends§ 39.13 byadding the following newairworthiness directive (AD): 2012-22-16 Pratt & Whitney Division: Amendment 39-17253; Docket No. FAA-2012-0546; Directorate Identifier 2012-NE-15-AD. (a) EffectiveDate This AD is effective [INSERT DATE 35 DAYS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER]. (b) Affected ADs None. (c) Applicability This AD applies to all Pratt 

### & Whitney Division PW4050, PW4052, PW4056, PW4060,PW4060A,PW4060C,PW4062,PW4062A,PW4152,PW4156,PW4156A, PW4!58, PW4160, PW4460, PW4462, and PW4650 turbofan engines, including models 

### with any dash number suffix, 

### with 3rd 

### stage low-pressure turbine (LPT) duct segments part numbers (PINs) 50N095; 50N095-00I; 50N235; 50N235-001; 50N494-0l; 50N494- 001; 50N495-0I; or 50N495-001, installed. (d) Unsafe Condition This AD was prompted by 16 reports ofdamaged or failed 3"' stage LPTduct 

### segments. We are issuing this AD to preventfailure ofthe 3rd 

### stage LPT duct segments, 

### which could lead to LPT rotor damage, uncontained engine failure, and damage to the airplane. (e) Compliance Comply withthis AD within the compliance times specified, unless already done.

5(I) 3'' Stage LPT Duct Segments Removal from Service 

### At the next piece-part exposure after the effective date ofthis AD, remove from service 3'' stage LPTduct segments, PINs 50N095; 50N095-00I; 50N235; 50N235-001; 50N494-0I; 50N494-001; 50N495-0l; and 50N495-00I. (g) Installation Prohibition After the effective date ofthis AD, do not install into any engine any 3rd stage LPTduct segment, PIN 50N095; 50N095-001; 50N235; 50N235-001; 50N494-01; 50N494-00I; 50N495-0I; or 50N495-00I, that is atpiece-part exposure. (h) Definition 

### For the purpose ofthis AD, piece-part exposure is when the 3rd 

### stage LPT duct segment is removed from the engine and completely disassembled. (i) Alternative Methods ofCompliance (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, contactJames Gray, 

### Aerospace Engineer, Engine & 

### Propeller Directorate, FAA, 12 New England Executive Park, Burlington, MA 01803; phone: 781-238-7742; fax: 781-238-7199; e-mail: james.e.gray@faa.gov. 

### (2) Pratt & 

### Whitney Engine-Duct Segment, Third Stage LPT Assembly Service BulletinNo. PW4ENG 72-488 is related to this AD. (3) 

### For service infonnation identified in this AD, contact Pratt & 

### Whitney, 400 Main St., East Hartford, CT 06108; phone: 860-565-8770; fax: 860-565-4503. You may 

### review copies ofthe service information at the FAA, Engine & 

### Propeller Directorate, 12 NewEngland Executive Park, Burlington, MA. For infonnation on the availability ofthis material at the FAA, call781-238-7125.

6

### (k) Material Incorporated by 

### Reference None.

Issued in Burlington, Massachusetts, on October29,2012.

# a&~m 'Ua.QQ_JJ()MdtSJ Colleen M. D'Allessandro, Assistant Manager, Engine & Propeller Directorate, Aircraft Certification Service.

7