[Docket No. FAA-2015-2208; Directorate Identifier 2015-NE-19-AD] 

RIN 2120-AA64 

Airworthiness Directives; Honeywell International Inc. (Type Certificate previously 

held by AlliedSignal Inc., Garrett Turbine Engine Company) Turbofan Engines 

AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). 

SUM:MARY: We propose to adopt a new airworthiness directive (AD) for Honeywell 

International Inc. TFE731-4, -4R, -SAR, -SBR, and -5R turbofan engines. This proposed 

AD was prompted by a report of certain interstage turbine transition (ITT) ducts failing to 

meet containment capability requirements. This proposed AD would require replacing 

certain ITT ducts. We are proposing this AD to prevent failure of the ITT duct, which 

could lead to an uncontained part release, damage to the engine, 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, using the procedures found in 14 CFR 11.43 

and 11.45, by any of the following methods: 

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the 

instructions for submitting comments. 

• Fax: 202-493-2251. • Mail: U.S. Department of Transportation, Docket Operations, M-30, West 

Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washirigton, DC 

20590. 
Internet: https://myaerospace.honeywell.com/wps/portal/!ut/. 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-2015-2208; or in person at the Docket 

Management Facility 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 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: Joseph Costa, Aerospace Engineer, 

Los Angeles Aircraft Certification Office, FAA, Transport Airplane Directorate, 3960 

Paramount Blvd., Lakewood, CA 90712-4137; phone: 562-627-5246; fax: 562'627-5210; 

email: joseph.costa@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

We invite you to send any written relevant data, views, or arguments about this 

NPRM. Send your comments to an address listed under the ADDRESSES section. 

Include "Docket No. F AA-2015-2208; Directorate Identifier 2015-NE-19-AD" at the 

beginning of your comments. We specifically invite comments on the overall regulatory, 

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http://www.regulations.gov, including any personal information you provide. We will 

also post a report smnmarizing each substantive verbal contact we receive about this 

NPRM. 

Discussion 

While the Honeywell Aerospace Olomouc facility in the Czech Republic was 

reworking certain ITT ducts, forgings that were not properly heat treated were installed 

on the affected engines. The heat treatment is necessary for the ITT ducts, part number 

(PIN) 3075292-4, to meet mechanical properties and the containment capability 

requirements of the ITT duct design. ITT ducts with unacceptable containment capability, 

if not corrected, could result in an uncontained part release, damage to the engine, and 

damage to the airplane. 

Related Service Information under 1 CFR Part 51 

We reviewed Honeywell Service Bulletin (SB) No. TFE731-72-3789, dated 

March 23, 2015. The SB describes procedures for removing affected ITT ducts. This 

service information is reasonably available because the interested parties have access to it 

through their normal course of business or by the means identified in the ADDRESSES 

section of this NPRM. 

FAA's Determination 

We are proposing this NPRM because we evaluated all the relevant information 

and determined the unsafe condition described previously is likely to exist or develop in 

other products of the same type design. 

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U.S. registry. We also estimate that it would take about 2 hours per engine to comply 

with this proposed AD. The average labor rate is $85 per hour. We estimate that 

replacement parts would cost $15,000 per engine. Based on these figures, we estimate the 

total cost of the proposed AD to U.S. operators to be $712,990. 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 connnerce. 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, 

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(2) Is not a "significant rule" under the DOT Regulatory Policies and Procedures 

( 44 FR II 034, February 26, 1979), 

(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 of the 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): 

Honeywell International Inc. (Type Certificate previously held by AlliedSignal Inc., 

Garrett Turbine Engine Company): Docket No. F AA-2015-2208; Directorate 

Identifier 20 15-NE-19-AD. 

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None. 

(c) Applicability 

This AD applies to all Honeywell International Inc. TFE731-4, -4R, -5AR, -5BR, 

and -5R turbofan engines with an interstage turbine transition (ITT) duct, part number 

(PIN) 3075292-4, installed, with a serial number (SIN) listed in Table 2 of Honeywell 

Service Bulletin (SB) No. TFE731-72-3789, dated March 23,2015. 

(d) Unsafe Condition 

This AD was prompted by a report of certain ITT ducts failing to meet 

containment capability requirements. We are issuing this AD to prevent failure of the ITT 

duct, which could lead to an uncontained part release, damage to the engine, and damage 

to the airplane. 

(e) Compliance 

Comply with this AD within the compliance times specified, unless already done. 

(1) At the next removal of the ITT duct from the engine not to exceed 2,600 hours 

time-in-service after the effective date of this AD, remove the affected ITT duct and 

replace with a part eligible for installation. 

(2) Reserved. 

(f) Definitions 

For the purpose of this AD a part eligible for installation is an ITT duct with an 

SIN that is not listed in Table 2 of Honeywell SB No. TFE731-72-3789, dated March 23, 

2015 or, iflisted in Table 2 of this SB, was reworked using Honeywell SB No. TFE731-

72-3789, dated March 23,2015. 

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"P35864" near the ITT duct PIN and SIN markings. 

(h) Alternative Methods of Compliance (AMOCs) 

The Manager, Los Angeles Aircraft Certification Office, FAA, may approve 

A1v10Cs for this AD. Use the procedures found in 14 CFR 39.19 to make your request. 

(i) Related Information 

(1) For more information about this AD, contact Joseph Costa, Aerospace 

Engineer, Los Angeles Aircraft Certification Office, FAA, Transport Airplane 

Directorate, 3960 Paramount Blvd., Lakewood, CA 90712-4137; phone: 562-627-5246; 

fax: 562-627-5210; email: joseph.costa@faa.gov. 

(2) For service information identified in this AD contact Honeywell International 

Inc., Ill S 34'" Street, Phoenix, AZ 85034-2802; phone: 800-601-3099; Internet: 

https ://myaerospace.honeywell. corn!wps/portal/! uti. 

(3) 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. 

Issued in Burlington, Massachusetts, on October 22,2015. 

Colleen M. D'Alessandro, 

Directorate Manager, Engine & Propeller Directorate, 

Aircraft Certification Service. 

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