[Docket No. FAA-2015-4023; Directorate Identifier 2015-NE-29-AD; Amendment 

39-18445; AD 2016-06-14] 

RIN 2120-AA64 

Airworthiness Directives; General Electric Company Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. 

ACTION: Final rule. 

SUMMARY: We are adopting a new airworthiness directive (AD) for all General 

Electric Company (GE) CF6-80El turbofan engines with rotating compressor discharge 

pressure (CDP) seal, part munber (PIN) 1669M73P02, installed. This AD was prompted 

by repot1s from the manufacturer of cracks in the teeth of two rotating CDP seals found 

during engine shop visits. This AD requires stripping of the coating, inspecting, and 

recoating the teeth of the affected rotating CDP seals. We are issuing this AD to prevent 

cracking of the CDP seal teeth, uncontained part release, damage to the engine, and 

damage to the airplane. 

DATES: This AD is effective [INSERT DATE 35 DAYS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER]. 

The Director of the Federal Register approved the incorporation by reference of a 

certain publication listed in this AD as of[INSERT DATE 35 DAYS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER]. 

ADDRESSES: For service information identified in this final rule, contact General 

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

phone: 513-552-3272; email: aviation.fleetsupport@ge.com. You may view this service 

infonnation at the FAA, Engine & Propeller Directorate, 1200 District A venue, 
You may examine the AD docket on the Internet at http://www-.regulations.gov by 

searching for and locating Docket No. F AA-2015-4023; 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 AD, the regulatory evaluation, any comments 

received, and other information. The address for the Docket Office (phone: 

800-647-5527) is Document Management Facility, U.S. Department of Transportation, 

Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 

Jersey Avenue SE., Washington, DC 20590. 

FOR FURTHER INFORMATION CONTACT: Herman Mak, Aerospace Engineer, 

Engine Certification Office, FAA, Engine & Propeller Directorate, 1200 District Avenue, 

Burlington, MA 01803; phone: 781-238-7147; fax: 781-238-7199; email: 

herman.mak@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Discussion 

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 3 9 by 

adding an AD that would apply to all GE CF6-80El turbofan engines with rotating CDP 

seal, PIN 1669M73P02, installed. The NPRM published in the Federal Register on 

November 17, 2015 (80 FR 71747). The NPRM was prompted by reports of cracks in the 

teeth of two rotating CDP seals found during engine shop visits. The NPRM proposed to 

require stripping of the coating, inspecting, and recoating the teeth of the affected rotating 

CDP seals. We are issuing this AD to prevent cracking of the CDP seal teeth, 

uncontained part release, damage to the engine, and damage to the airplane. 

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Request to Clarify Definition 

Qantas, Air France, KLM Royal Dutch Airlines (KLM), and GE Aviation 

requested that the shop visit definition be clarified to allow for randomly occurring 

exemptions. Including exemptions would not increase the time between full shop visits. 

We agree. We changed the shop visit definition to include specific conditions that 

do not qualify as shop visits. 

Request to Clarify the Shop Visit Definition 

KLM and Air France requested we clarify the phrase "separation of pairs of major 

mating engine flanges". 

We agree. We changed the definition for engine shop visit. 

Request to Change Compliance Time 

Qantas requested a more restrictive compliance time for engines that experience 

blade-out events and a less restrictive compliance time of next part exposure for all other 

affected engines. Only engines that experience blade-out conditions require urgent 

compliance times. 

We disagree. The compliance times in the NPRM were derived from analysis that 

includes the risks asSociated with engines with and without blade-out events. We did not 

change this AD. 

Request to Clarify Compliance 

Qantas requested that we clarify the specific type of stationary CDP seal repair 

and that we clarify what is considered a replaced stationary CDP seal. 

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We partially agree. We agree with the concern for accidental installation of 

borazon-nickel coated rotating CDP seals because the NPRM does not preclude this 

scenario. We disagree with expanding this AD to include spare parts because ADs 

address unsafe conditions of engines, not spare parts. We changed this AD by adding an 

installation prohibition paragraph to address this concern. 

Request to Change Credit for Previous Action 

KLM requested the Credit for Previous Action paragraph allow for other 

approved original equipment manufacturer approved procedures for stripping and 

recoating rotating CDP seal teeth. KLM recoated two CDP seals using a procedure 

approved by GE. 

We disagree. It is unknown whether previous recoating procedures are equivalent 

to the procedures" specified in the Credit for Previous Action paragraph of this AD. Any 

party may submit a request for an Alternative Method of Compliance using the 

procedures listed in this AD. We did not change this AD. 

Additional Changes 

We clarified paragraphs ( e)(2)(i) and ( e)(2)(ii) of this AD. 

We updated the cost estimate. We changed the Costs of Compliance paragraph of 

this AD by increasing the number of affected engines by four and updating the costs 

accordingly. 

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We also determined that these changes will not increase the economic burden on 

any operator or increase the scope of this AD. 

Related Service Information under 1 CFR part 51 

We reviewed GE Service Bulletin (SB) CF6-80El S/B 72-0529, Revision 01, 

dated August 21, 2015. The SB describes procedures for stripping, inspecting, and 

replacing the seal tooth coating on the affected rotating CDP seals. 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. 

Other Related Service Information 

We reviewed GE CF6-80El (GEK99376) Engine Manual, Revision 42, dated 

March 15,2014. The engine manual describes acceptable repair procedures for the seal 

teeth. 

Costs of Compliance 

We estimate that this AD will affect I 0 engines installed on airplanes ofU .S. 

registry. We also estimate that it will take about 7.15 hours per engine to comply with 

this AD. The average labor rate is $85 per hour. Parts would cost about $7,835 per 

engine. Based on these figures, we estimate the total cost of this AD to U.S. operators to 

be $84,428. 

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. 

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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 

This AD will not have federalism implications under Executive Order 13132. This 

AD will not have a substantial direct 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 that this AD: 

(I) Is not a "significant regulatory action" under Executive Order 12866, 

(2) Is not a "significant rule" under 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. 

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1. The authority citation for part 3 9 continues to read as follows: 

Authority: 49 U.S.C. IQ6(g), 40113,44701. 

§ 39.13 [Amended] 

2. The FAA amends§ 39.13 by adding the following new airworthiness directive 

(AD): 

2016-xx-xx General Electric Company: Amendment 39-18xxx; Docket 

No. FAA-2015-4023; Directorate Identifier 2015-NE-29-AD. 

(a) Effective Date 

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 General Electric Company (GE) CF6-80El turbofan 

engines with rotating compressor discharge pressure (CDP) seals, part number (PIN) 

1669M73P02, installed. 

(d) Unsafe Condition 

This AD was prompted by reports from the manufacturer of cracks in the teeth of 

two rotating CDP seals found during engine shop visits. We are issuing this AD to 

prevent cracking of the CDP seal teeth, which can lead to uncontained part release, 

damage to the engine, and damage to the airplane. 

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1669M73P02. Use paragraph 3.C.(2) ofGE Service Bulletin (SB) CF6-80El SIB 72-

0529, Revision 01, dated August 21, 2015 to do the strip coating, inspecting, and 

recoating, as follows: 

(i) For engines that have had stationary CDP seal, PIN 1347M28G02, replaced or 

stationary CDP seal honeycomb repaired; strip coating, inspect, and recoat the teeth of 

the rotating CDP seal at the next engine shop visit. 

(ii) For engines that have not had stationary CDP seal, PIN 1347M28G02, 

replaced or stationary CDP seal honeycomb repaired; strip coating, inspect, and recoat 

the teeth of the rotating CDP seal at the next part exposure of the rotating CDP seal. 

(f) Installation Prohibition 

After the effective date of this AD, do not install any rotating CDP seal, PIN 

1669M73P02, that has not had its seal teeth iecoated using procedures specified in ESM 

72-31-10, REPAIR 002 ofGE CF6-80El (GEK99376) Engine Manual, Revision 42, 

dated March 15, 2014, into any engine. 

(g) Definitions 

(1) For the purpose of this AD, exposure of the rotating CDP seal is defined as 

removal of the compressor rear frame from the high-pressure compressor (HPC) module. 

(2) For the purpose ofthis AD, an engine shop visit is defined as the induction of 

an engine into the shop for maintenance involving the separation of any major mating 

engine flanges, except that the separation of engine flanges solely for the following 

purposes is not considered a shop visit: 

(i) Transportation without subsequent engine maintenance. 

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72-0504 "Quick-Tum Workscope Procedure to Replace CF6-80El Stage 1 HPT Blades". 

(3) For the purpose of this AD, a stationary CDP seal is replaced if at any 

previous shop visit, the seal has been removed and a different seal is installed. 

(h) Credit for Previous Action 

You may take credit for the actions that are required by paragraph (e) of this AD 

if the actions were performed before the effectiVe date of this AD using the procedures in 

ESM 72-31-10, REPAIR 002 of the GE CF6-80El (GEK99376) Engine Manual, 

Revision 42, dated March 15,2014, or earlier versions. 

(i) 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 Herman Mak, Aerospace 

Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 1200 

District Avenue, Burlington, MA 01803; phone: 781-238-7147; fax: 781-238-7199; 

email: herman.mak@faa.gov. 

(k) Material Incorporated by Reference 

(1) The Director of the Federal Register approved the incorporation by reference 

(IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR 

part 51. 

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(ii) Reserved. (3) ForGE service information identified in this AD, contact General Electric 

Company, GE Aviation, Room 285, 1 Neumann Way, Cincinnati, 01-1 45215; phone: 

513-552-3272; email: aviation.fleetsupport@ge.corn. 

(4) You may view this service information at FAA, Engine & Propeller 

Directorate, 1200 District Avenue, Burlington, MA. For information on the availability of 

this material at the FAA, call 781-238-7125. 

(5) You may view this service information at the National Archives and Records 

Administration (NARA). For information on the availability of this material at NARA, 

call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibrlocations.htrnl. 

Issued in Burlington, Massachusetts, on March 16,2016. 

Ann C. Mollica, 

Acting Manager, Engine & Propeller Directorate, 

Aircraft Certification Service. 

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