Document ID: FAA-2019-0683-0010
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: General Electric Company Turbofan Engines
Posted Date: 2020-06-19T04:00Z

[Federal Register Volume 85, Number 119 (Friday, June 19, 2020)]
[Rules and Regulations]
[Pages 37000-37003]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-13126]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0683; Project Identifier AD-2020-00149-E; 
Amendment 39-21149; AD 2020-13-04]
RIN 2120-AA64

Airworthiness Directives; General Electric Company Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2017-09-06 
for all General Electric Company (GE) GEnx-1B and GEnx-2B model 
turbofan engines. AD 2017-09-06 required updating electronic engine 
control (EEC) full authority digital electronic control (FADEC) 
software on GEnx-1B and GEnx-2B turbofan engines and replacing a 
certain fan hub frame assembly part installed on GEnx-2B turbofan 
engines. This AD requires updating EEC software on GEnx-1B and GEnx-2B 
engines and replacing a certain fan hub frame assembly part installed 
on GEnx-2B engines. This AD was prompted by the development of a design 
change by GE to remove the unsafe condition. The FAA is issuing this AD 
to address the unsafe condition on these products.

DATES: This AD is effective July 24, 2020.

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: geae.aoc@ge.com. You 
may view this service information at the FAA, Airworthiness Products 
Section, Operational Safety Branch, 1200 District Avenue, Burlington, 
MA 01803. For information on the availability of this material at the 
FAA, call 781-238-7759. It is also available on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2019-
0683.

Examining the AD Docket

    You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2019-
0683; 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 final rule, the regulatory evaluation, any comments received, and 
other information. The address for Docket Operations is 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: Mehdi Lamnyi, Aerospace Engineer, ECO 
Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: (781) 
238-7743; fax: (781) 238-7199; email: Mehdi.Lamnyi@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to supersede AD 2017-09-06, Amendment 39-18868 (82 FR 
21111, May 5, 2017), (``AD 2017-09-06''). AD 2017-09-06 applied to all 
GE GEnx-1B and GEnx-2B model turbofan engines. The NPRM published in 
the Federal Register on November 19, 2019 (84 FR 63820). The NPRM was 
prompted by the development of a design change by GE to remove the 
unsafe condition. The NPRM proposed to require updating EEC FADEC 
software on GEnx-1B and GEnx-2B model turbofan engines and replacing a 
certain fan hub frame assembly part installed on GEnx-2B model turbofan 
engines. The FAA is issuing this AD to address the unsafe condition on 
these products.

Comments

    The FAA gave the public the opportunity to participate in 
developing this final rule. The following presents the comments 
received on the NPRM and the FAA's response to each comment.

Request To Clarify Compliance Time

    The Air Line Pilots Association, International (ALPA), commented 
that it is unclear why the compliance time to remove the affected fan 
hub stator assembly booster outlet guide vanes (BOGV) of ``before 
further flight,'' would occur after an independent engine shop visit. 
ALPA suggested either removal or clarification of the ``before further 
flight'' compliance time requirement.
    This AD supersedes AD 2017-09-06 (82 FR 21111, May 5, 2017), which 
specified removal of certain fan hub stator assembly BOGV at the next 
engine shop visit after its effective date (June 9, 2017). This AD 
retains the requirement

[[Page 37001]]

to remove the fan hub stator assembly BOGV at the next engine shop 
visit after June 9, 2017, the effective date of the superseded AD, but 
adds the option of compliance ``or before further flight, whichever 
occurs later.'' This added compliance time option provides operators 
that have yet to comply with AD 2017-09-06 the option to comply with 
this AD, averting a situation wherein operators may be in violation of 
this AD upon its publication.

Request To Extend Compliance Time

    American Airlines (American) requested that the compliance time be 
extended from 120 days to 180 days for removal of the affected EEC 
software. American noted that there is a concurrent requirement in 
Boeing Service Bulletin B787-73-0051, Issue 001, dated July 9, 2019, to 
update the software for the Loadable Diagnostic Information (LDI) on 
some configurations of B787 model airplanes. American indicated that 
the EEC software that supersedes version B195 will not properly 
function without the LDI update on those aircraft. Accomplishment of 
the LDI update requires an additional three work hours, bringing the 
total to four work hours, during which the Boeing Service Bulletin (SB) 
instructs that no other maintenance tasks be performed. American 
commented that extending the compliance time will allow operators to 
better accommodate for these requirements for the out of service time.
    The FAA disagrees. Based on information received by the FAA, the 
EEC software, version B200 or later, will provide the Ice Crystals 
Icing (ICI) mitigation logic regardless of whether the LDI software is 
installed. The LDI update is not required to address the unsafe 
condition. The FAA did not change this AD.

Request To Add Terminating Action

    American and Japan Airlines (JAL) commented that since this AD is 
replacing AD 2017-09-06, which includes a terminating action for 
paragraphs (g) and (i) of AD 2013-24-01 (78 FR 70851; November 27, 
2013) (``AD 2013-24-01''), the referenced terminating action should 
also be included in this AD. American noted that updating the EEC 
software removes the unsafe icing condition identified in the AD.
    The FAA agrees that updating the EEC FADEC software on the affected 
engines removes the unsafe condition. The FAA disagrees with adding a 
terminating action to this AD. Since the issuance of FAA AD 2017-09-06, 
the FAA has approved alternative methods of compliance (AMOCs) to 
paragraphs (g) and (h) of AD 2013-24-01 for Boeing model 747-8 
airplanes, powered by GEnx-1B model engines, and for Boeing model 747-8 
and 747-8F airplanes, powered by GEnx-2B model engines. These AMOCs 
replaced the need for the terminating action previously included in AD 
2017-19-06.

Request To Clarify Compliance Language

    American commented that previous ADs involving EEC FADEC software 
have required operators to ``remove [EEC FADEC] software, version B195 
or earlier from the engine and from service.'' Previously published ADs 
also stated, ``. . . do not operate any GE GEnx[hyphen]1B engine with 
[EEC FADEC] software version B180 [or B175, for earlier AD] or earlier 
installed. . . .'' Additionally, American indicated the SBs that 
replace the B195 software do not require removal of earlier software, 
just the installation of later software. American requested 
clarification that the proposed AD only forbids operation of software 
B195 or earlier, without specifying removal of old software. American 
noted that specifying removal of the software can cause confusion 
regarding whether deleting software from the File Server Module is also 
required.
    The FAA agrees. This AD does not need to require removal of the 
previous version of software that is being updated. The FAA has revised 
the compliance language in paragraph (g)(1) of this AD to require 
installation of software that is eligible for installation. The FAA 
also added a definition to this AD, defining software that is eligible 
for installation.

Request To Clarify Applicability

    JAL noted that paragraph (g)(1) of this AD requires the removal of 
EEC software, version B195 or earlier, from the engine and from 
service. JAL asked if ``the engine'' includes the spare engine or if it 
means the engine installed on the airplane. JAL noted that paragraph 
(e)(1) of AD 2017-09-06 says ``Thirty days after the effective date of 
this AD, do no operate any GEnx-1B engine with electronic engine 
control EEC full authority digital engine control (FADEC) software 
version B180 or earlier, installed.'' JAL commented that even if the 
EEC software of the spare engine is a version B180, or earlier, JAL 
could still install the EEC software, version B185, during engine 
installation and avoid operating the engine with EEC, software version 
B180 or earlier. JAL indicated that it believes the intent of this NPRM 
is to avoid operating the engine on aircraft with EEC software, version 
B195 or earlier. Therefore, JAL believes the installation of EEC 
software, version B195, on spare engines or spare EECs is acceptable. 
JAL requested that the FAA clarify the intent of this AD.
    The FAA notes that ADs cannot be enforced until the product is 
operated. Per 14 CFR 39.7 ``Anyone who operates a product that does not 
meet the requirements of an applicable airworthiness directive is in 
violation of this section.'' The intent of this AD is to prevent 
operation of any affected engine installed on an aircraft with EEC 
software, version B195 or earlier. The requirements of this AD do not 
apply to spare engines and spare EECs. Therefore, no change to this AD 
is needed.

Request To Include Latest Service Information

    GE Aviation requested that the FAA include a reference to the 
Revision 1 of GEnx-2B SB 72-00241 in the Related Service Information 
section of this AD. GE indicated the latest revision of this SB adds a 
repair process for the BOGV.
    The FAA agrees with adding the SB reference to the Related Service 
Information section of this AD to include GEnx-2B SB 72-00241 R01, 
dated July 4, 2019. The FAA is also adding a definition of a part 
eligible for installation to this AD, which clarifies that the operator 
may replace the affected BOGV P/N B1316-00720, with a repaired BOGV P/N 
B1316-06008. The required actions section of this AD mandates removal 
of the affected BOGV P/N B1316-00720 and replacing it with a part 
eligible for installation.

Request To Change Definition of Engine Shop Visit

    GE Aviation requested the FAA change the definition of an ``engine 
shop visit'' in paragraph (h) of this AD. GE Aviation stated that 
accomplishment of a top/bottom case removal procedure should be 
excluded from the definition to allow for an instance where maintenance 
is required in the high-pressure compressor module but further 
extensive flange separation is not required, thus resulting in ability 
to reduce engine maintenance time. Additionally, GE Aviation stated 
that this procedure is listed as a shop visit definition exception in 
GE Service Bulletin 72-0000.
    The FAA disagrees. The FAA has not received documentation to 
support any determination regarding the impact on safety by allowing 
this exception to the definition of a shop visit.

[[Page 37002]]

Support for the AD

    United Airlines and the Boeing Company commented that they support 
the proposed rule.

Conclusion

    The FAA reviewed the relevant data, considered the comments 
received, and determined that air safety and the public interest 
require adopting this final rule with the changes described previously 
and minor editorial changes. The FAA determined that these minor 
changes:
     Are consistent with the intent that was proposed in the 
NPRM for addressing the unsafe condition; and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM.
    The FAA also determined that these changes will not increase the 
economic burden on any operator or increase the scope of this final 
rule.

Related Service Information

    The FAA reviewed GE GEnx-1B Service Bulletin (SB) 73-0082 R00, 
dated July 9, 2019, and GE GEnx-2B SB 73-0077 R00, dated October 29, 
2018. The service information describes procedures for installation of 
new EEC software on GEnx-1B and GEnx-2B model turbofan engines. The FAA 
also reviewed GE GEnx-2B SB 72-0241 R01, dated July 4, 2019. The 
service information describes removal and installation procedures for 
the fan hub stator assembly BOGV.

Costs of Compliance

    The FAA estimates that this AD affects 110 engines installed on 
airplanes of U.S. registry. The FAA estimates that 15 engines will 
require replacement of the fan hub stator assembly BOGV.
    The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Install EEC software..................  1 work-hour x $85 per                 $0             $85          $9,350
                                         hour = $85.
Replace fan hub stator assembly BOGV..  60 work-hours x $85 per          387,800         392,900       5,893,500
                                         hours = $5,100.
----------------------------------------------------------------------------------------------------------------

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.
    The FAA is 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

    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:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Will not affect intrastate aviation in Alaska, and
    (3) 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:

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:
0
a. Removing Airworthiness Directive 2017-09-06, Amendment 39-18868 (82 
FR 21111, May 5, 2017); and
0
b. Adding the following new airworthiness directive (AD):

2020-13-04 General Electric Company: Amendment 39-21149; Docket No. 
FAA-2019-0683; Project Identifier AD-2020-00149-E.

(a) Effective Date

    This AD is effective July 24, 2020.

(b) Affected ADs

    This AD replaces AD 2017-09-06, Amendment 39-18868 (82 FR 21111, 
May 5, 2017).

(c) Applicability

    This AD applies to all General Electric Company (GE) GEnx-1B and 
GEnx-2B model turbofan engines.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7600, Engine 
Controls.

(e) Unsafe Condition

    This AD was prompted by reports of GEnx-1B and GEnx-2B model 
turbofan engines experiencing power loss in ice crystal icing 
conditions. The FAA is issuing this AD to prevent engine failure. 
The unsafe condition, if not addressed, could result in loss of 
thrust control and damage to the airplane.

(f) Compliance

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

(g) Required Actions

    (1) Within 120 days after the effective date of this AD, install 
electronic engine control (EEC) software that is eligible for 
installation.
    (2) At the next engine shop visit after June 9, 2017 (the 
effective date of AD 2017-09-06), or before further flight, 
whichever occurs later, remove from service all GE GEnx-2B67, -
2B67B, and -2B67/P fan hub stator assembly booster outlet guide 
vanes (BOGV), part number (P/N) B1316-00720, and replace with a part 
eligible for installation.

(h) Definition

    (1) For the purpose of this AD, an ``engine shop visit'' is the 
induction of an engine into the shop for maintenance involving the 
separation of pairs of major mating engine case flanges, except for 
the following which do not constitute an engine shop visit:
    (i) Separation of engine flanges solely for the purposes of 
transportation without subsequent maintenance does not constitute an 
engine shop visit.

[[Page 37003]]

    (ii) Separation of engine flanges solely for the purpose of 
replacing the fan or propulsor without subsequent maintenance does 
not constitute an engine shop visit.
    (2) For the purpose of this AD, EEC software that is eligible 
for installation is:
    (i) For GE GEnx-1B model turbofan engines, EEC software that is 
version B200 or later.
    (ii) For GEnx-2B model turbofan engines, EEC software that is 
version C090 or later.
    (3) For the purpose of this AD, a part eligible for installation 
is a fan hub stator assembly BOGV which:
    (i) Is not P/N B1316-00720; or,
    (ii) Was previously a P/N B1316-00720, but has been repaired and 
modified into P/N B1316-07637.

(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) of this AD. You may email your request 
to: ANE-AD-AMOC@faa.gov.
    (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

    For more information about this AD, contact Mehdi Lamnyi, 
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: (781) 238-7743; fax: (781) 238-7199; 
email: Mehdi.Lamnyi@faa.gov.

(k) Material Incorporated by Reference

    None.

    Issued on June 12, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-13126 Filed 6-18-20; 8:45 am]
BILLING CODE 4910-13-P