Document ID: FAA-2019-0683-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: General Electric Company Turbofan Engines
Posted Date: 2019-11-19T05:00Z

[Federal Register Volume 84, Number 223 (Tuesday, November 19, 2019)]
[Proposed Rules]
[Pages 63820-63822]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-24786]

=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0683; Product Identifier 2015-NE-02-AD]
RIN 2120-AA64

Airworthiness Directives; General Electric Company Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to supersede Airworthiness Directive (AD) 
2017-09-06, which applies to all General Electric Company (GE) GEnx-1B 
and GEnx-2B model turbofan engines. AD 2017-09-06 requires updating 
electronic engine control (EEC) full authority digital electronic 
control (FADEC) software and replacing a certain fan hub frame assembly 
part installed on GEnx-2B turbofan engines. Since the FAA issued AD 
2017-09-06, GE has developed a design change to remove the unsafe 
condition. This proposed AD would require removal from service of 
certain EEC FADEC software on GEnx-1B and GEnx-2B model turbofan 
engines and would also require replacing the affected fan hub frame 
assembly booster outlet guide vanes. The FAA is proposing this AD to 
address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by January 3, 
2020.

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 https://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.

[[Page 63821]]

    For service information identified in this NPRM, 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, 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.

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 NPRM, the regulatory evaluation, any comments received, and other 
information. The street address for Docket Operations is listed above. 
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Herman Mak, Aerospace Engineer, ECO 
Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-
238-7147; fax: 781-238-7199; email: herman.mak@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites 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-2019-0683; 
Product Identifier 2015-NE-02-AD'' at the beginning of your comments. 
The FAA specifically invites comments on the overall regulatory, 
economic, environmental, and energy aspects of this NPRM. The FAA will 
consider all comments received by the closing date and may amend this 
NPRM because of those comments.
    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 proposed AD.

Discussion

    The FAA issued AD 2017-09-06, Amendment 39-18868 (82 FR 21111, May 
5, 2017), (``AD 2017-09-06''), for all GE GEnx-1B and GEnx-2B model 
turbofan engines. AD 2017-09-06 requires replacing certain EEC FADEC 
software with versions eligible for installation. AD 2017-09-06 also 
requires removing from service certain GE GEnx-2B67, -2B67B, and -2B67/
P fan hub stator assembly booster outlet guide vanes. AD 2017-09-06 
resulted from reports of GEnx-1B and GEnx-2B model turbofan engines 
experiencing power loss in ice crystal icing (ICI) conditions. The FAA 
issued AD 2017-09-06 to prevent engine failure, loss of thrust control, 
and damage to the airplane.

Actions Since AD 2017-09-06 Was Issued

    Since the FAA issued AD 2017-09-06, the FAA learned that the 
required actions in that AD do not adequately address the unsafe 
condition. Engine rollback still occurs as ICI mitigation software 
installed as required by AD 2017-09-06 does not activate during the 
climb phase of airplane flight. In response, GE developed revised 
software that will activate while the airplane is climbing. This AD 
requires removing from service certain EEC FADEC software.

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 FADEC software on GEnx-1B and GEnx-2B model turbofan engines. 
The FAA also reviewed GE GEnx-2B SB 72-0241 R00, dated March 16, 2016. 
The service information describes removal and installation procedures 
for the fan hub stator assembly booster outlet guide vane.

FAA's Determination

    The FAA is 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 certain requirements of AD 2017-09-
06. This proposed AD would continue to require replacement of certain 
fan hub stator assembly booster outlet guide vanes installed on GE 
GEnx-2B67, -2B67B, and -2B67/P engines. This proposed AD would also 
require removing from service certain EEC FADEC software versions 
installed on GE GEnx-1B and GEnx-2B model turbofan engines.

Costs of Compliance

    The FAA estimates that this proposed 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 booster 
outlet guide vanes.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
               Action                         Labor cost            Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Remove EEC software................  1 work-hour x $85 per hour               $0             $85          $9,350
                                      = $85.
Replace fan hub stator assembly      60 work-hours x $85 per             387,800         392,900       5,893,500
 booster outlet guide vanes.          hour = $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.
    This AD is issued in accordance with authority delegated by the 
Executive Director, Aircraft Certification Service,

[[Page 63822]]

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

    The FAA has determined that this proposed AD would not have 
federalism 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) 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.

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) 
2017-09-06, Amendment 39-18868 (82 FR 21111, May 5, 2017), and adding 
the following new AD:

General Electric Company: Docket No. FAA-2019-0683; Product 
Identifier 2015-NE-02-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by January 3, 
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, for GE 
GEnx-1B model turbofan engines, remove electronic engine control 
(EEC) full authority digital engine control (FADEC) software, 
version B195 or earlier, from the engine and from service.
    (2) Within 120 days after the effective date of this AD, for GE 
GEnx-2B model turbofan engines, remove EEC FADEC software, version 
C085 or earlier, from the engine and from service.
    (3) 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, part number B1316-00720, and replace with a part eligible for 
installation.

(h) Definition

    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:
    (1) Separation of engine flanges solely for the purposes of 
transportation without subsequent maintenance does not constitute an 
engine shop visit.
    (2) Separation of engine flanges solely for the purpose of 
replacing the fan or propulsor without subsequent maintenance does 
not constitute an engine shop visit.

(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: 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

    (1) For more information about this AD, contact Herman Mak, 
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: 781-238-7147; fax: 781-238-7199; email: 
herman.mak@faa.gov.
    (2) For service information identified in this AD, 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 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 November 12, 2019.
Robert J. Ganley,
Manager, Engine and Propeller Standards Branch, Aircraft Certification 
Service.
[FR Doc. 2019-24786 Filed 11-18-19; 8:45 am]
 BILLING CODE 4910-13-P