Airworthiness Directives; General Electric Company Turbofan Engines

[Federal Register Volume 85, Number 196 (Thursday, October 8, 2020)]
[Rules and Regulations]
[Pages 63443-63445]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-22267]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0902; Project Identifier AD-2020-01174-E; 
Amendment 39-21273; AD 2020-20-17]
RIN 2120-AA64


Airworthiness Directives; General Electric Company Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all 
General Electric Company GE90-110B1 and GE90-115B model turbofan 
engines. This AD was prompted by an in-service occurrence of loss of 
engine thrust control resulting in uncommanded high thrust. This AD 
prohibits dispatch of an airplane if certain status messages are 
displayed on the engine indicating and crew alerting system (EICAS) and 
if certain conditions are present per the manufacturer's service 
information. As a terminating action, this AD requires revision of the 
existing FAA-approved minimum equipment list (MEL) by incorporating 
into the MEL the dispatch restrictions listed in this AD. The FAA is 
issuing this AD to address the unsafe condition on these products.

DATES: This AD is effective October 23, 2020.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of October 23, 
2020.
    The FAA must receive comments on this AD by November 23, 2020.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
    <bullet> Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments.
    <bullet> Fax: 202-493-2251.
    <bullet> 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.
    <bullet> Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this final rule, contact 
General Electric Company, 1 Neumann Way, Cincinnati, OH 45215; phone: 
513-552-3272; email: [email protected]; website: www.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-2020-0902.

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-2020-
0902; 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, any comments received, and other information. The 
street address for the Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Stephen Elwin, Aerospace Engineer, ECO 
Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-
238-7236; fax: 781-238-7199; email: [email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA received a report from the manufacturer of an in-service 
loss of engine thrust control that occurred on October 27, 2019, 
resulting in uncommanded high thrust. Analysis by the manufacturer 
found accumulated thermal cycles of the MN4 integrated circuit in the 
full authority digital engine control (FADEC) through normal operation 
causes the solder ball joints to wear out and eventually fail over 
time. The failure was preceded by an inbound FADEC EICAS ``ENG EEC C1'' 
status message one flight before the in-service occurrence. This 
condition, if not addressed, could result in loss of engine thrust 
control and reduced control of the airplane. The FAA is issuing this AD 
to address the unsafe condition on these products.

FAA's Determination

    The FAA is issuing this AD because the agency 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.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed GE GE90-100 Service Bulletin (SB) 73-0117, R01, 
dated August 5, 2020. The SB describes procedures for checking for an 
inbound FADEC EICAS ``ENG EEC C1'' status message and corresponding 
conditions. 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.

AD Requirements

    This AD prohibits dispatch of the airplane if certain status 
messages are displayed on the EICAS and if certain conditions are 
present per the manufacturer's service information. As a terminating 
action, this AD requires, within 120 days of the effective date of this 
AD, revision of the existing FAA-approved MEL by incorporating into the 
MEL the dispatch restrictions listed in paragraph (g) of this AD.

Interim Action

    The FAA considers this AD interim action. The manufacturer is still 
reviewing the unsafe condition and the FAA will consider further 
rulemaking.

Justification for Immediate Adoption and Determination of the Effective 
Date

    Section 553(b)(3)(B) of the Administrative Procedure Act (APA) (5 
U.S.C.) authorizes agencies to dispense with notice and comment 
procedures for rules when the agency, for ``good cause,'' finds that 
those procedures are ``impracticable, unnecessary, or contrary to the 
public interest.'' Under this section, an agency, upon finding good 
cause, may issue a final rule without seeking comment prior to 
issuance. Further, Section 553(d) of the APA authorizes agencies to 
make rules effective in less than 30 days, upon a finding of good 
cause.
    An unsafe condition exists that requires the immediate adoption of 
this AD without providing an opportunity for public comments prior to 
adoption. The FAA has found that the risk to the flying public 
justifies foregoing notice and comment prior to adoption of this rule. 
On October 27, 2019, a Boeing Company Model 777-300 airplane powered by 
GE GE90-115B model turbofan engines experienced an

[[Page 63444]]

unresponsive throttle for 11.5 minutes during descent into Abu Dhabi 
International Airport. The pilot regained throttle control of the 
engine while at an altitude over 15,000 feet, continued the descent to 
the airport, and landed without further incident. The investigation by 
the manufacturer discovered that cracking of the MN4 integrated circuit 
solder ball caused one of the FADEC channels to read an erroneous 
thrust lever resolver angle value which, once selected, caused an 
erroneously high thrust command. The manufacturer issued service 
information in August 2020 that provides procedures for status message 
checks of the FADEC required by this AD.
    The FAA considers the failure of the MN4 integrated circuit in the 
FADEC an urgent safety issue, requiring immediate review of FADEC EICAS 
status messages and possible prohibition of departure of the airplane.
    Accordingly, notice and opportunity for prior public comment are 
impracticable and contrary to public interest pursuant to 5 U.S.C. 
553(b)(3)(B).
    In addition, the FAA finds that good cause exists pursuant to 5 
U.S.C. 553(d) for making this amendment effective in less than 30 days.

Comments Invited

    The FAA invites you to send any written data, views, or arguments 
about this final rule. Send your comments to an address listed under 
the ADDRESSES section. Include the docket number FAA-2020-0902 and 
Project Identifier AD-2020-01174-E at the beginning of your comments. 
The most helpful comments reference a specific portion of the final 
rule, explain the reason for any recommended change, and include 
supporting data. The FAA will consider all comments received by the 
closing date and may amend this final rule because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
https://www.regulations.gov, including any personal information you 
provide. The FAA will also post a report summarizing each substantive 
verbal contact received about this final rule.

Confidential Business Information

    Confidential Business Information (CBI) is commercial or financial 
information that is both customarily and actually treated as private by 
its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), 
CBI is exempt from public disclosure. If your comments responsive to 
this AD contain commercial or financial information that is customarily 
treated as private, that you actually treat as private, and that is 
relevant or responsive to this AD, it is important that you clearly 
designate the submitted comments as CBI. Please mark each page of your 
submission containing CBI as ``PROPIN.'' The FAA will treat such marked 
submissions as confidential under the FOIA, and they will not be placed 
in the public docket of this AD. Submissions containing CBI should be 
sent to Stephen Elwin, Aerospace Engineer, ECO Branch, FAA, 1200 
District Avenue, Burlington, MA 01803. Any commentary that the FAA 
receives which is not specifically designated as CBI will be placed in 
the public docket for this rulemaking.

Regulatory Flexibility Act

    The requirements of the Regulatory Flexibility Act (RFA) do not 
apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt 
a rule without prior notice and comment. Because the FAA has determined 
that it has good cause to adopt this rule without notice and comment, 
RFA analysis is not required.

Costs of Compliance

    The FAA estimates that this AD affects 206 engines installed on 
airplanes of U.S. registry.
    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
----------------------------------------------------------------------------------------------------------------
Revise the existing MEL............  1 work-hour x $85 per hour               $0             $85         $17,510
                                      = $85.
----------------------------------------------------------------------------------------------------------------

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, and
    (2) Will not affect intrastate aviation in Alaska.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

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 adding the following new airworthiness 
directive (AD):


[[Page 63445]]


2020-20-17 General Electric Company: Amendment 39-21273; Docket No. 
FAA-2020-0902; Project Identifier AD-2020-01174-E.

(a) Effective Date

    This AD is effective October 23, 2020.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all General Electric Company GE90-110B1 and 
GE90-115B model turbofan engines.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by an in-service occurrence of loss of 
engine thrust control resulting in uncommanded high thrust. The FAA 
is issuing this AD to prevent dispatch of the airplane when certain 
faults caused by degradation of the MN4 integrated circuit in the 
full authority digital engine control (FADEC) are displayed and 
certain FADEC conditions are present. The unsafe condition, if not 
addressed, could result in loss of engine thrust control and reduced 
control of the airplane.

(f) Compliance

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

(g) Required Actions

    After the effective date of this AD, notwithstanding the 
provisions of the operator's minimum equipment list (MEL), dispatch 
of an airplane is prohibited if the engine indicating and crew 
alerting system (EICAS) displays the status message ``ENG EEC C1 L'' 
or ``ENG EEC C1 R'' and any condition is present that is listed in 
the Accomplishment Instructions, paragraphs 3.A.(2)(f), 3.A.3(a), or 
3.A.(4) of GE GE90-100 Service Bulletin (SB) 73-0117 R01, dated 
August 5, 2020.

(h) Terminating Action

    As terminating action for the requirements of paragraph (g) of 
this AD, within 120 days of the effective date of this AD, revise 
the existing FAA-approved MEL by incorporating into the MEL the 
dispatch restrictions listed in paragraph (g) of this AD as a 
required operation or maintenance procedure. Specific alternative 
MEL wording to accomplish the actions specified in paragraph (g) of 
this AD can be approved by the operator's principal operations or 
maintenance inspector.

(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: [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

    For more information about this AD, contact Stephen Elwin, 
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: 781-238-7236; fax: 781-238-7199; email: 
[email protected].

(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.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) General Electric Company (GE) GE90-100 Service Bulletin 73-
0117 R01, dated August 5, 2020.
    (ii) [Reserved]
    (3) For GE service information identified in this AD, contact 
General Electric Company, 1 Neumann Way, Cincinnati, OH 45215; 
phone: 513-552-3272; email: [email protected]; website: 
www.ge.com.
    (4) You may view this service information at 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.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, email: [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on September 25, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-22267 Filed 10-7-20; 8:45 am]
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