[Docket No. F AA-2015-3585; Directorate Identifier 2015-NE-22-AD; Amendment 

39-18384; AD 2015-28-01] 

RlN 2120-AA64 

Airworthiness Directives; Engine Alliance Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. 

SUMMARY: We are adopting a new airworthiness directive (AD) for certain Engine 

Alliance (EA) GP7270 turbofan engines. This AD was prompted by the manufacturer 

informing us that the inspection criteria and repair procedures in the maintenance manual 

for aft bolt holes of the high-pressure compressor (I-IPC) cone shaft on the affected 

engines is incorrect. This AD requires inspection of the I-IPC cone shaft and repair of 

affected parts, if needed. We are issuing this AD to prevent failure of the HPC cone shaft, 

which could lead to 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]. 

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 AD, contact Engine Alliance, 

400 Main St., East Hartford, CT 06108, MIS 169-10, phone: 800-565-0140; email: 

help24@pw.utc.com; Internet: sp.engineallianceportal.com. You may view this service 

information at the FAA, Engine & Propeller Directorate, 1200 District Avenue, 
searching for and locating Docket No. FAA-2015-3585; 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 ofTranspmtation, 

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

Jersey Avenue SE., Washington, DC 20590. 

FOR FURTHER INFORMATION CONTACT: Kyle Gustafson, Aerospace Engineer, 

Engine & Propeller Directorate, FAA, 1200 District Avenue, Burlington, MA 01803; 

phone: 781-238-7183; fax: 781-238-7199; email: kyle.gustafson@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Discussion 

·we issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by 

adding an AD that would apply to certain EA GP7270 turbofan engines. The NPRM 

published in the Federal Register on October I, 2015 (80 FR 59081). The NPRM was 

prompted by the manufacturer infonning us that the inspection criteria and repair 

procedures in the maintenance manual for aft bolt holes of the HPC cone shaft, also 

referred to as the "J-IPC forward stubshaft," for the affected engines is incorrect. The 

NPR1v1 proposed to require inspection of the HPC cone shaft and repair of affected parts, 

if needed. We are issuing this AD to prevent failure of the HPC cone shaft, which could 

lead to uncontained engine failure and damage to the airplane. 

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Request to Add Engine Models 

EA requested that we expand the applicability to include the GP7272 and GP7277 

engine models. 

We disagree. There are no GP7272 or GP7277 engines in service nor have any 

been delivered. New engines would be delivered with corrected service information and 

would not be impacted by this AD. We did not change this AD. 

Request to Change the Unsafe Condition Statement 

EA requested that the unsafe condition statement be changed from '"We are 

issuing this AD to prevent failure of the HPC cone shaft, which could lead to uncontained 

engine failure and damage to the airplane." to "We are issuing this AD to prevent a 

hazardous engine condition." The reason for this request is that no HPC cone shaft 

failures have occurred in the field. 

We disagree. The unsafe condition statement describes the condition we are tTying 

to prevent and is the justification for this AD. It does not describe what has occurred in 

the past. We did not change this AD. 

Request to Change Various Paragraphs 

EA requested that we revise the part nomenclature in the Applicability, 

Compliance, and Installation Prohibition paragraphs and in the unsafe condition 

statement to include both "cone shaft" and "forward stubshaft." The part is referenced as 

a "cone shaft" in this AD and engine and component manuals; however, it is referred to 

as a "forward stubshaft" in the service bulletins (SBs). 

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AD. 

Request to Revise the Compliance 

EA requested that the Compliance paragraph be revised to include the word "pits" 

when describing the inspection criteria. 

We agree. We revised paragraph (e)(!) and(!)(!) of this AD from " ... nicks, 

dents, and scratches ... " to " ... nicks, dents, pits, and scratches .... " 

Request to Change the Compliance 

EA requested that we replace "Do not reinstall the HPC cone shaft if the aft bolt 

hole has a nick, dent, or scratch that is greater than 0.002 inch in depth" in paragraph 

(e)(l) of this AD with "Comply v..rith the Accomplishment Instructions in EA SB No. 

EAGP7-72-330 if the aft bolt hole has a nick, dent, pit, or scratch that is greater than the 

serviceable limit." 

We disagree. The current engine manual has an approved repair procedure for 

damage that is more severe than the installation requirements of this AD. It is not 

necessary to restate what is already allowed by the engine manual. We did not change 

this AD. 

Request to Change Service Information 

EA requested that the phrase "or later" be used when referring to SBs. 

We disagree. We are only authorized to mandate use ofSBs that we have 

reviewed and which are published. Since future revisions of SBs are not yet published, 

we are not authorized to mandate their use. We did not change this AD. 

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applicable part, and (2) has a nick, dent, or scratch in an HPC cone shaft aft bolt hole that 

is greater than the serviceable limit." 

We disagree. The intent of the Installation Prohibition paragraph is to mandate the 

new serviceable limit of 0.002 inch for damage to the inner diameter of the bolt holes for 

the entire GP7270 fleet. Any parts with damage beyond this limit may be repaired using 

the approved procedures listed in the engine manual, provided that you include shot 

peening as required by paragraph (!)(2) of this AD. We did not change this AD. 

Conclusion 

We reviewed the relevant data, considered the comments received, and 

determined that air safety and the public interest require adopting this AD with the 

changes described previously. 

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

any operator or increase the scope of this AD. 

Costs of Compliance 

We estimate that this AD affects zero engines installed on airplanes of U.S. 

registry. The average labor rate is $85 per hour. Based on these figures, we estimate the 

cost of this AD on U.S. operators to be $0. 

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 tl1e scope of the Agency's 

authority. 

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or finds 

necessary for safety in air commerce. This regulation is vvithin the scope of that authority 

because it addresses an unsafe condition that is likely to exist or develop on products 

identified in this mlemaking 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 goverrunent. 

For the reasons discussed above, I certify that this AD: 

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

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

( 44 FR II 034, February 26, I979), 

(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. 

Adoption of the Amendment 

Accordingly, under the authority delegated to me by the Administrator, the FAA 

amends 14 CFR part 39 as follows: 

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

(AD): 

2015-28-01 Engine Alliance: Amendment 39-18384; Docket No. FAA-2015-3585; 

Directorate Identifier 2015-NE-22-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 Engine Alliance (EA) GP7270 turbofan engines with a highpressure compressor (HPC) cone shaft, part number 382-100-907-0, installed. 

(d) Unsafe Condition 

This AD was prompted by the manufacturer informing us that the inspection and 

repair criteria in the maintenance manual for aft bolt holes of the I-IPC cone shaft on the 

affected engines is inconect. We are issuing this AD to prevent failure of the HPC cone 

shaft, which could lead to Wlcontained engine failure and damage to the airplane. 

(e) Compliance 

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

(1) For HPC cone shafts with serial numbers listed in EA Service Bulletin (SB) 

No. EAGP7-72-330, dated July 21, 2015, inspect the inner diameter of the HPC cone 

shaft aft bolt holes for nicks, dents, pits, and scratches before accumulating 9,000 cycles 

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9,000 CSN. Use paragraph 1 of the Accomplishment Instructions in EA SB No. EAGP?-

72-329 to do the shot peening. 

(f) Installation Prohibition 

After the effective date of this AD, do not install an HPC cone shaft on any 

engine with the following: 

(1) any nicks, dents, pits, or scratches in an HPC cone shaft aft bolt hole that is 

greater than 0.002 inch in depth; or 

(2) any repair of an HPC cone shaft aft bolt hole that did not include shot peening. 

(g) Alternative Methods of Compliance (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. You may email your request 

to: ANE-AD-AMOC@faa.gov. 

(h) Related Information 

For more information about this AD, contact Kyle Gustafson, Aerospace 

Engineer, Engine & Propeller Directorate, FAA, 1200 District A venue, Burlington, MA 

01803; phone: 781-238-7183; fax: 781-238-7199; email: kyle.gustafson@faa.gov. 

(i) 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. 

(2) You must use this service information as applicable to do the actions required 

by this AD, unless the AD specifies otherwise. 

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400 Main St., East Hartford, CT 06108, M/S 169-1 0; phone: 800-565-0140; email: 

help24@pw.utc.corn; Internet: sp.engineallianceportal.com. 

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

Directorate, 1200 District A venue, 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.html. 

Issued in Burlington, Massachusetts, on January 13, 2016. 

Gaetano Sciortino, 

Acting Directorate Manager, Engine & Propeller Directorate, Aircraft Certification Service. 

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