Document ID: FAA-2018-0406-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: General Electric Company Turbofan Engines
Posted Date: 2018-06-25T04:00Z

[Federal Register Volume 83, Number 122 (Monday, June 25, 2018)]
[Proposed Rules]
[Pages 29474-29476]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-13444]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0406; Product Identifier 2013-NE-30-AD]
RIN 2120-AA64

Airworthiness Directives; General Electric Company Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to supersede Airworthiness Directive (AD) 2017-07-
04, which applies to General Electric Company (GE) GE90-110B1 and GE90-
115B turbofan engines with certain high-pressure compressor (HPC) rotor 
stage 2-5 spools installed. AD 2017-07-04 resulted from reports of 
cracks in HPC rotor stage 2-5 spool aft spacer arms. Since we issued AD 
2017-07-04, GE released a new service bulletin (SB) that increases the 
number of affected HPC rotor stage 2-5 spools. Additionally, we learned 
that we inadvertently omitted certain HPC rotor stage 2-5 spools from 
the applicability of AD 2017-07-04. This proposed AD would require 
removing certain HPC rotor stage 2-5 spools from service before 
reaching the new reduced life limit and replacing them with parts 
eligible for installation. We are proposing this AD to correct the 
unsafe condition on these products.

DATES: We must receive comments on this proposed AD by August 9, 2018.

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, 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 NPRM, contact General 
Electric Company, One Neumann Way, Room 285, Cincinnati, OH; phone: 
513-552-3272; email: [email protected]. You may view this service 
information at the FAA, Engine and Propeller Standards Branch, 1200 
District Avenue,

[[Page 29475]]

Burlington, MA 01803. For information on the availability of this 
material at the FAA, call 781-238-7759.

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-2018-
0406; or in person at Docket Operations between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays. The AD docket contains 
this NPRM, the regulatory evaluation, any comments received, and other 
information. The street address for Docket Operations (phone: 800-647-
5527) is listed above. Comments will be available in the AD docket 
shortly after receipt.

FOR FURTHER INFORMATION CONTACT: David Bethka, Aerospace Engineer, ECO 
Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-
238-7129; fax: 781-238-7199; email: [email protected].

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2018-0406; 
Product Identifier 2013-NE-30-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 
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 proposed AD.

Discussion

    We issued AD 2017-07-04, Amendment 39-18842 (82 FR 16728, April 6, 
2017), (``AD 2017-07-04''), for GE GE90-110B1 and GE90-115B turbofan 
engines with certain HPC rotor stage 2-5 spools installed. AD 2017-07-
04 requires removing these spools from service at times determined by a 
drawdown plan. AD 2017-07-04 resulted from reports of cracks in HPC 
rotor stage 2-5 spool aft spacer arms. We issued AD 2017-07-04 to 
prevent failure of a critical life-limited rotating engine part, which 
could result in an uncontained engine failure and damage to the 
airplane.

Actions Since AD 2017-07-04 Was Issued

    Since we issued AD 2017-07-04, GE released GE SB GE90-100 SB 72-
0714 R01, dated February 16, 2018, for the HPC rotor stage 2-5 spools, 
which increases the number of affected parts.
    Additionally, GE and Boeing provided comments on AD-2017-07-04 that 
some HPC rotor stage 2-5 spools listed in AD 2013-24-17 (superseded by 
AD 2017-07-04), were omitted from AD 2017-07-04.

Related Service Information Under 1 CFR Part 51

    We reviewed GE SB GE90-100 SB 72-0499 R01, dated February 5, 2014; 
GE SB GE90-100 SB 72-0659 R01, dated February 18, 2016; and GE SB GE90-
100 SB 72-0714 R01, dated February 16, 2018.
    GE SB GE90-100 SB 72-0499 R01 describes procedures for 
identification and removal from service of HPC rotor stage 2-5 spools 
that use the original seal tooth coating process. GE SB GE90-100 SB 72-
0659 R01 describes procedures for identification and removal from 
service of HPC rotor stage 2-5 spools that use a modified seal tooth 
coating process. GE SB GE90-100 SB 72-0714 R01 describes procedures for 
identification and removal from service of HPC rotor stage 2-5 spools 
that use the modified seal tooth coating process, without coating 
between the seal teeth.
    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.

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.

Proposed AD Requirements

    This proposed AD would retain all requirements of AD 2017-07-04. 
This proposed AD would require removing certain HPC rotor stage 2-5 
spools from service at times specified in the required actions section.

Costs of Compliance

    We estimate that this proposed AD affects 85 engines installed on 
airplanes of U.S. registry.
    We estimate the following costs to comply with this proposed AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Paragraph (g)(1) Spools Replacement...  0 work-hours x $85 per          $229,737        $229,737      $5,054,214
                                         hour = $0.
Paragraph (g)(2) Spools Replacement...  0 work-hours x $85 per            39,048          39,048       2,460,024
                                         hour = $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 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.
    This AD is issued in accordance with authority delegated by the 
Executive Director, Aircraft Certification Service, as authorized by 
FAA Order 8000.51C. In accordance with that order, issuance of ADs is 
normally a function of the Compliance and Airworthiness Division, but 
during this transition period, the Executive Director has delegated the 
authority to issue ADs applicable to engines, propellers, and 
associated appliances to the Manager, Engine and Propeller Standards 
Branch, Policy and Innovation Division.

Regulatory Findings

    We have determined that this proposed AD would not have federalism

[[Page 29476]]

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, or on the distribution 
of power and responsibilities among the various levels of government.
    For the reasons discussed above, I certify that the 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

0
1. The authority citation for part 39 continues to read as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701.

Sec.  39.13   [Amended]

0
2. The FAA amends Sec.  39.13 by removing Airworthiness Directive (AD) 
2017-07-04, Amendment 39-18842 (82 FR 16728, April 6, 2017), and adding 
the following new AD:

    General Electric Company: Docket No. FAA-2018-0406; Product 
Identifier 2013-NE-30-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by August 9, 
2018.

(b) Affected ADs

    This AD replaces AD 2017-07-04, Amendment 39-18842 (82 FR 16728, 
April 6, 2017) (``AD 2017-07-04'').

(c) Applicability

    This AD applies to General Electric Company (GE) GE90-110B1 and 
GE90-115B turbofan engines with HPC rotor stage 2-5 spools, with:
    (1) A serial number listed in either, paragraph 4, Appendix A of 
GE Service Bulletin (SB) No. GE90-100 SB 72-0499 R01, dated February 
5, 2014, in paragraph 4, Appendix A of GE SB GE90-100 SB 72-0659 
R01, dated February 18, 2016, or in paragraph 4, Appendix A, of GE 
SB GE90-100 SB 72-0714 R01, dated February 16, 2018.
    (2) A part number (P/N) 351-103-109-0, P/N 351-103-110-0, P/N 
351-103-147-0 or P/N 351-103-152-0, with any serial number.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7230, Turbine Engine 
Compressor Section.

(e) Unsafe Condition

    This AD was prompted by reports of cracks in HPC rotor stage 2-5 
spool aft spacer arms. We are issuing this AD to prevent failure of 
the HPC rotor stage 2-5 spools. The unsafe condition, if not 
addressed, could result in uncontained spool release, damage to the 
engine, and damage to the airplane.

(f) Compliance

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

(g) Required Actions

    (1) Remove from service HPC rotor stage 2-5 spools with serial 
numbers listed in paragraph 4, Appendix A, of GE SB GE90-100 SB 72-
0659 R01, dated February 18, 2016, as follows, or before further 
flight, whichever occurs later:
    (i) For spools with fewer than 4,500 flight CSN as of April 21, 
2017, remove before exceeding 5,000 CSN.
    (ii) For spools with 4,500 CSN or more but fewer than 5,200 CSN 
as of April 21, 2017, remove within 500 CIS but not to exceed 5,500 
CSN.
    (iii) For spools with 5,200 CSN or more but fewer than 5,600 CSN 
as of April 21, 2017, remove within 300 CIS but not to exceed 5,800 
CSN.
    (iv) For spools with 5,600 CSN or more but fewer than 5,800 CSN 
as of April 21, 2017, remove within 200 CIS but not to exceed 5,850 
CSN.
    (v) For spools with 5,800 CSN or more but fewer than 6,000 CSN 
as of April 21, 2017, remove within 50 CIS but not to exceed 6,000 
CSN.
    (vi) For spools with 6,000 CSN or more as of April 21, 2017, 
remove before the next flight.
    (2) Remove from service HPC rotor stage 2-5 spools listed in 
paragraph (c)(2) of this AD and HPC rotor stage 2-5 spools with 
serial numbers listed in paragraph 4, Appendix A, of GE SB GE90-100 
SB 72-0714 R01, dated February 16, 2018, before exceeding 8,200 CSN, 
or before further flight, whichever occurs later.

(h) Installation Prohibition

    (1) After the effective date of this AD, do not install or 
reinstall onto any engine, any HPC rotor stage 2-5 spool with a 
serial number listed in paragraph 4, Appendix A, of GE SB No. GE90-
100 SB 72-0499 R01, dated February 5, 2014, or paragraph 4, Appendix 
A, of GE SB GE90-100 SB72-0659 R01, dated February 18, 2016, that 
exceeds 5,000 CSN.
    (2) After the effective date of this AD, do not install or 
reinstall onto any engine, any HPC rotor stage 2-5 spool listed in 
paragraph (c)(2) of this AD, or HPC rotor stage 2-5 spool with a 
serial number listed in paragraph 4, Appendix A, of GE SB GE90-100 
SB 72-0714 R01, dated February 16, 2018, that exceeds 8,200 CSN.

(i) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, ECO Branch, FAA, has the authority to approve 
AMOCs for this AD, if requested using the procedures found in 14 CFR 
39.19. In accordance with 14 CFR 39.19, send your request to your 
principal inspector or local Flight Standards District Office, as 
appropriate. If sending information directly to the manager of the 
certification office, send it to the attention of the person 
identified in paragraph (j)(1) of this AD. You may email your 
request to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(j) Related Information

    (1) For more information about this AD, contact David Bethka, 
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: 781-238-7129; fax: 781-238-7199; email: 
[email protected].
    (2) For service information identified in this AD, contact 
General Electric Company, One Neumann Way, Room 285, Cincinnati, OH; 
phone: 513-552-3272; email: [email protected]. You may view this 
referenced service information at the FAA, Engine and Propeller 
Standards Branch, 1200 District Avenue, Burlington, MA 01803. For 
information on the availability of this material at the FAA, call 
781-238-7759.

    Issued in Burlington, Massachusetts, on June 19, 2018.
Robert J. Ganley,
Manager, Engine and Propeller Standards Branch, Aircraft Certification 
Service.
[FR Doc. 2018-13444 Filed 6-22-18; 8:45 am]
 BILLING CODE 4910-13-P