DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA-2012-1288; Directorate Identifier 2012-NE-37-AD] 

RIN 2120-AA64 

Airworthiness Directives; General Electric Company Turbofan Engines 

AGENCY: Federal Aviation Administration (FAA), DOT. 

ACTION: Notice of proposed rulemaking (NPRM). 

[4910-13-P] 

SUMMARY: We propose to adopt a new airworthiness directive (AD) for all General 

Electric Company (GE) CF34-8C and CF34-8E turbofan engines with certain part 

numbers (PIN) of operability bleed valves (OBV) installed. This proposed AD was 

prompted by three failure events of ring lock fuel fittings on the OBV. Two of those 

events led to an engine fire. This proposed AD would require the affected OBVs be 

removed from service and replaced with OBVs eligible for installation. We are proposing 

this AD to prevent failure of OBV ring lock fuel fittings, engine fuel leakage, 

uncontrolled fire, 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, 

One Neumann Way, MD Y-75, Cincinnati, OH; phone: 513-552-2913; email: 

geae.aoc@ge.com; and website: www.GE.com. You view 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://wwvv.regulations. gov; 

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: John Frost, Aerospace Engineer, 

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

01803; phone: 781-238-7756; fax: 781-238-7199; email: john.frost@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

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

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

Include "Docket No. FAA-2012-1288; Directorate Identifier 2012-NE-37-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 

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comments received by the closing date and may amend this proposed AD because of 

those comments. 

We will post all comments we receive, without change, to 

http://w\nv.regulati ons.gov, including any personal information you provide. We will 

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

proposed AD. 

Discussion 

We received reports of three failure events of OBV ring lock fuel fittings on GE 

CF34-8C turbofan engines. Two of those events led to an engine fire. Investigation 

revealed that the ring lock fittings failed due to fatigue caused by improper broaching of 

the OBV housing during manufacture, and, improper installation of the ring lock fittings 

during OBV assembly. GE CF34-8E turbofan engines also use the affected OBVs and 

would be affected by this proposed AD. This condition, if not corrected, could result in 

failure of OBV ring lock fuel fittings, engine fuel leakage, uncontrolled fire, and damage 

to the airplane. 

Relevant Service Information 

We reviewed GE Service Bulletin (SB) No. CF34-8C-AL S/B 75-0017, dated 

September 14 2012. We also reviewed GE SB No. CF34-8E-AL S/B 75-0012, dated 

September 14, 2012. These bulletins describe procedures for removing from service 

OBVs having an affected PIN. 

FAA's Determination 

We are proposing this AD 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 proposed AD would require for all GE CF34-8C and CF34-8E turbofan 

engines with an OBV PIN 4121T67P02, PIN 4121T67P03, PIN 4121T67P04, parts 

manufacturer approval (PMA) PIN 392155-2, PMA PIN 392155-3, or PMA PIN 392155-

4 installed, removal of the OBV from service. 

Costs of Compliance 

We estimate that this proposed AD would affect 300 engines installed on 

airplanes of U.S. registry. We also estimate that it would take about two hours per engine 

to perform the actions required by this proposed AD, and that the average labor rate is 

$85 per hour. Required parts would cost about $25,000 per engine. Based on these 

figures, we estimate the total cost ofthe proposed AD to U.S. operators to be $7,551 ,000. 

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 

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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), 

(3) Will not affect intrastate aviation in Alaska, 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-2012-1288; Directorate Identifier 2012-

NE-37-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 General Electric Company (GE) CF34-8C1 , CF34-8C5, CF34-

8C5A1 , CF34-8C5A2, CF34-8C5A3, CF34-8C5B1 , CF34-8E2, CF34-8E2A1 , CF34-

8E5, CF34-8E5A1 , CF34-8E5A2, CF34-8E6, and CF34-8E6A1 turbofan engines, with 

an operability bleed valve (OBV) part number (PIN) 4121T67P02, PIN 4121T67P03, PIN 

4121 T67P04, parts manufacturer approval (PMA) PIN 392155-2, PMA PIN 392155-3, or 

PMA PIN 392155-4, installed. 

(d) Unsafe Condition 

This AD was prompted by three failure events of ring lock fuel fittings on the 

OBV. Two of those events led to an engine fire . We are issuing this AD to prevent failure 

of OBV ring lock fuel fittings, engine fuel leakage, uncontrolled fire, and damage to the 

airplane. 

(e) Compliance 

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

(f) Remove OBVs 

(1) For OBVs with fewer than 6,000 operating hours since new on the effective 

date ofthis AD, remove the OBV from service before accumulating 12,000 operating 

hours since new, or within four years after the effective date of this AD, whichever 

occurs first. 

(2) For OBVs with 6,000 or more operating hours since new on the effective date 

of this AD, remove the OBV from service before accumulating an additional 6,000 

operating hours, or within two years after the effective date of this AD, whichever occurs 

first. 

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(g) 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. 

(h) Related Information 

(1) For more information about this AD, contact John Frost, Aerospace Engineer, 

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

01803 ; phone: 781-238-7756; fax: 781-238-7199; email: john.frost@faa.gov. 

(2) Refer to GE SB No. CF34-8C-AL S/B 75-0017, dated September 14 2012, 

and SB No. CF34-8E-AL S/B 75-0012, dated September 14, 2012, for related 

information. 

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

Neumann Way, MD Y-75, Cincinnati, OH; phone: 513-552-2913; email: 

geae.aoc@ge.com; and website: www.GE.com. You may view 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, 

call781-238-7125. 

Issued in Burlington, Massachusetts, on December 4, 20 12 .• 

Robert J. Ganley, 

Acting Manager, Engine & Propeller Directorate, 

Aircraft Certification Service. 

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