DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. F AA-2015-0165; Directorate Identifier 2015-NE-02-AD] 

RIN 2120-AA64 

Airworthiness Directives; General Electric Company 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 all General 

Electric Company (GE) GEnx turbofan engine models. This proposed AD was prompted 

by reports ofGEnx-1B and GEnx-2B engines experiencing power loss in ice crystal icing 

(ICI) conditions. This proposed AD would preclude the use of full authority digital 

engine control (F ADEC) software, version B 175 or earlier, in GEnx-1 B engines, and the 

use ofFADEC software, version C065 or earlier, in GEnx-2B engines. We are proposing 

this AD to prevent engine failure, 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, using the procedures found in 14 CFR 11.43 

and 11.45, by any ofthe 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., Washington, DC 

20590. 
• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., 

Monday through Friday, except Federal holidays. 

For service information identified in this proposed AD, contact General Electric 

Company, GE Aviation, Room 285, 1 Neumann Way, Cincinnati, OH 45215; phone: 

513-552-3272; email: geae.aoc@ge.com. You may view this service information at the 

FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 

01803. For information on the availability ofthis 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-2015-0165; 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: Tomasz Rakowski, Aerospace 

Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New 

England Executive Park, Burlington, MA 01803 ; phone: 781-238-7735 ; fax: 781-238-

7199; email: tomasz.rakowski@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. FAA-2015-0165 ; Directorate Identifier 2015-NE-02-AD" at the 

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

economic, environmental, and energy aspects of this NPRM. We will consider all 

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comments received by the closing date and may amend this NPRM because of 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 we receive about this 

NPRM. 

Discussion 

We propose to adopt a new AD for all GE GEnx turbofan engine models. This 

proposed AD was prompted by reports ofGEnx-lB and GEnx-2B engines experiencing 

power loss in ICI conditions. Five engines experienced non-serviceable mechanical 

damage. One engine did not recover power due to mechanical damage. This condition, if 

not corrected, could result in engine failure , loss of thrust control, and damage to the 

airplane. This proposed AD would preclude the use of FADEC software, version B 175 or 

earlier in GEnx-1B engines, and the use ofFADEC software, version C065 or earlier, in 

GEnx-2B engines. We are proposing this AD to prevent engine failure , loss of thrust 

control, and damage to the airplane. 

Related Service Information under 1 CFR Part 51 

We reviewed GE GEnx-1B Service Bulletin (SB) No. 73-0036, dated January 6, 

2015 , and GE GEnx-2B SB No. 73-0035, dated September 16, 2014. The SBs describe 

procedures for installing FADEC software on GE GEnx-1B and GEnx-2B engine models. 

This service information is reasonably available; see ADDRESSES for ways to access 

this service information. 

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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Proposed AD Requirements 

This NPRM would preclude the use ofF ADEC software, version B 175 or earlier, 

in GEnx-1B engines, and the use ofFADEC software, version C065 or earlier, in GEnx2B engines. 

Costs of Compliance 

We estimate that this proposed AD will affect 80 engines installed on airplanes of 

U.S. registry. We also estimate that it will take about 1 hour per engine to comply with 

this proposed AD. The average labor rate is $85 per hour. No parts are required. Based on 

these figures, we estimate the total cost of the proposed AD to U.S. operators to be 

$6,800. 

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 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 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 13 132. 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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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), 

(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): 

General Electric Company: Docket No. FAA-2015-0165; Directorate Identifier 2015-

NE-02-AD. 

(a) Comments Due Date 

We must receive comments by [INSERT DATE 60 DAYS AFTER DATE OF 

PUBLICATION IN THE Federal Register]. 

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(b) Affected ADs 

None. 

(c) Applicability 

This AD applies to all General Electric Company (GE) GEnx-1B model turbofan 

engines with full authority digital engine control (F ADEC) software version B 175 or 

earlier, installed, and GEnx-2B model turbofan engines with F ADEC software version 

C065 or earlier, installed. 

(d) Unsafe Condition 

This AD was prompted by reports ofGEnx-lB and GEnx-2B engines 

experiencing power loss in ice crystal icing (ICI) conditions. We are issuing this AD to 

prevent engine failure, loss of thrust control, and damage to the airplane. 

(e) Compliance 

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

(1) Thirty days after the effective date of this AD, do not operate any GE GEnx1 B engine with FADEC software version B 175 or earlier, installed in the electronic 

engine control (EEC). 

(2) Thirty days after the effective date of this AD, do not operate any GE GEnx2B engine with F ADEC software version C065 or earlier, installed in the EEC. 

(f) Alternative Methods of Compliance (AMOCs) 

The Manager, Engine Certification Office, FAA, may approve AMOCs to 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 this AD, contact Tomasz Rakowski, Aerospace 

Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New 

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England Executive Park, Burlington, MA 01803 ; phone: 781-238-7735 ; fax: 781-238-

7199; email: tomasz.rakowski@faa.gov. 

(2) GE GEnx-1B Service Bulletin (SB) No. 73-0036, dated January 6, 2015, and 

GE GEnx-2B SB No. 73-0035, dated September 16, 2014, which are not incorporated by 

reference in this proposed AD, can be obtained from GE using the contact information in 

paragraph (g)(3) ofthis proposed AD. 

(3) For service information identified in this proposed AD, contact General 

Electric Company, GE Aviation, Room 285, 1 Neumann Way, Cincinnati, OH 45215 ; 

phone: 513-552-3272; email: geae.aoc@ge.com. 

( 4) You may view this 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, call 781-238-7125. 

Issued in Burlington, Massachusetts, on March 6, 2015. 

Ann C. Mollica, 

Acting Directorate Manager, Engine & Propeller Directorate, 

Aircraft Certification Service. 

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