Document ID: FAA-2020-0371-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: General Electric Company Turbofan Engines
Posted Date: 2020-04-10T04:00Z

[Federal Register Volume 85, Number 70 (Friday, April 10, 2020)]
[Proposed Rules]
[Pages 20211-20213]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-07565]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0371; Project Identifier AD-2019-00124-E]
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: The FAA proposes to adopt a new airworthiness directive (AD) 
for all General Electric Company (GE) CF6-80C2A1, CF6-80C2A2, CF6-
80C2A3, CF6-80C2A5, CF6-80C2A5F, CF6-80C2A8, CF6-80C2B1, CF6-80C2B1F, 
CF6-80C2B2, CF6-80C2B2F, CF6-80C2B4, CF6-80C2B4F, CF6-80C2B5F, CF6-
80C2B6, CF6-80C2B6F, CF6-80C2B6FA, CF6-80C2B7F, CF6-80C2B8F, and CF6-
80C2D1F model turbofan engines. This proposed AD was prompted by 
reports of incidents that resulted in a significant fuel loss during 
flight and an in-flight shutdown (IFSD) of the engine. This proposed AD 
would require initial and repetitive shim checks of the hydromechanical 
unit/main engine control (HMU/MEC) idler adapter on the accessory 
gearbox (AGB) assembly and, depending on the results of the shim check, 
possible replacement of the inserts on the HMU/MEC idler adapter. As a 
terminating action to the repetitive shim checks, this proposed AD 
would also require a protrusion check and a pull-out test and 
replacements of inserts on the HMU/MEC idler adapter that fail either 
test. 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 May 26, 
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.
    For service information identified in this NPRM, contact General 
Electric Company, 1 Newman Way, Cincinnati, OH 45215, United States; 
phone: (513) 552-3272; email: aviation.fleetsupport@ae.ge.com. You may 
view this referenced service information at the FAA, Engine & 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-2020-
0371; 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, 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: Matthew Smith, Aerospace Engineer, ECO 
Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-
238-7735; fax: 781-238-7199; email: matthew.c.smith@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2020-0371; 
Project Identifier AD-2019-00124-E'' 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.
    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 proposed AD.

Confidential Business Information

    Confidential Business Information (CBI) is commercial or financial 
information that is both customarily and actually treated as private by 
its owner.

[[Page 20212]]

Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is 
exempt from public disclosure. If your comments responsive to this NPRM 
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 NPRM, 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 NPRM. Submissions containing CBI should be 
sent to Matthew Smith, 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.

Discussion

    The FAA received reports regarding incidents on GE CF6-80C2 model 
turbofan engines that resulted in fuel loss during flight and an IFSD 
of the engine. The incidents resulted from inserts on the HMU/MEC idler 
adapter on the AGB assembly pulling out of the housing. An 
investigation by the manufacturer discovered improperly cut threads on 
the inserts and erroneous instructions in the maintenance manual, which 
contributed to poor thread engagement. This condition, if not 
addressed, could result in failure of the HMU/MEC, engine fire, and 
damage to the airplane.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed GE CF6-80C2 Service Bulletin (SB) 72-1577 R01, 
dated August 16, 2019. The SB describes procedures for performing shim 
checks of the HMU/MEC idler adapter. 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

    The FAA is proposing 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.

Proposed AD Requirements

    This proposed AD would require initial and repetitive shim checks 
of the HMU/MEC idler adapter on the AGB assembly and, depending on the 
results of the shim checks, replacement of the inserts on the HMU/MEC 
idler adapter. As a terminating action to the repetitive shim checks, 
this proposed AD would also require a protrusion check and a pull-out 
test and replacements of inserts on the HMU/MEC idler adapter that fail 
either test.

Costs of Compliance

    The FAA estimates that this proposed AD affects 555 engines 
installed on airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                         Parts       Cost per      Cost on U.S.
                 Action                            Labor cost             cost        product        operators
----------------------------------------------------------------------------------------------------------------
Shim check..............................  1.00 work-hour x $85.00 per      $0.00          $85.00         $47,175
                                           hour = $85.00.
Protrusion Check/Pull-out test..........  4.00 work-hours x $85.00          0.00          340.00         188,700
                                           per hour = $340.00.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary 
replacements that would be required based on the results of the 
proposed shim check. The FAA has no way of determining the number of 
aircraft that might need these replacements:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replace HMU/MEC idler adapter insert..........  4.00 work-hours x $85.00 per              $50.00         $390.00
                                                 hour = $340.00.
----------------------------------------------------------------------------------------------------------------

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

    The FAA 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 this 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.

[[Page 20213]]

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 adding the following new airworthiness 
directive (AD):

General Electric Company: Docket No. FAA-2020-0371; Project 
Identifier AD-2019-00124-E.

(a) Comments Due Date

    The FAA must receive comments by May 26, 2020.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to General Electric Company (GE) CF6-80C2A1, 
CF6-80C2A2, CF6-80C2A3, CF6-80C2A5, CF6-80C2A5F, CF6-80C2A8, CF6-
80C2B1, CF6-80C2B1F, CF6-80C2B2, CF6-80C2B2F, CF6-80C2B4, CF6-
80C2B4F, CF6-80C2B5F, CF6-80C2B6, CF6-80C2B6F, CF6-80C2B6FA, CF6-
80C2B7F, CF6-80C2B8F, and CF6-80C2D1F model turbofan engines that 
underwent an engine shop visit prior to November 1, 2018.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7321, Fuel Control/
Turbine Engines.

(e) Unsafe Condition

    This AD was prompted by failure of the hydromechanical unit/main 
engine control (HMU/MEC) on the accessory gearbox (AGB) assembly. 
The FAA is issuing this AD to prevent failure of the HMU/MEC. The 
unsafe condition, if not addressed, could result in engine fire and 
damage to the airplane.

(f) Compliance

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

(g) Required Actions

    (1) Perform a shim check of the HMU/MEC idler adapter inserts in 
accordance with paragraph 3.B.(1) of GE CF6-80C2 Service Bulletin 
(SB) 72-1577 R01, dated August 16, 2019, within 1,200 flight hours 
after the effective date of this AD.
    (2) Thereafter, perform a repetitive shim check of the HMU/MEC 
idler adapter inserts in accordance with paragraph 3.B.(1) of GE 
CF6-80C2 SB 72-1577 R01, dated August 16, 2019 within every 1,200 
flight hours since last shim check.
    (3) If any HMU/MEC idler adapter insert fails the shim check 
required by paragraph (g)(1) or (2) of this AD, perform the 
following prior to further flight:
    (i) Retorque the bolts at each bolt location that failed the 
shim check, in accordance with paragraph 3.B.(1)(c) of GE CF6-80C2 
SB 72-1577 R01, dated August 16, 2019.
    (ii) Perform the shim check again, in accordance with paragraph 
(g)(1) of this AD. If the shim check fails again, perform the 
terminating action required by paragraph (h) of this AD.

(h) Terminating Action

    As a terminating action to the repetitive shim check 
requirements of paragraph (g)(2) and (g)(3) of this AD, and as 
required by paragraph (g)(3)(ii) of this AD, perform the following:
    (1) Do a protrusion check at all eight bolt locations in 
accordance with paragraph 3.C.(3) of GE CF6-80C2 SB 72-1577 R01, 
dated August 16, 2019.
    (2) Do a pull-out test at all eight bolt locations in accordance 
with paragraph 3.C.(4) of GE CF6-80C2 SB 72-1577 R01, dated August 
16, 2019.
    (3) If the inserts on the HMU/MEC idler adapter fail the 
protrusion check or pull-out test required by paragraph (h)(1) or 
(2) of this AD, replace the inserts in accordance with paragraph 
3.C.(5) of GE CF6-80C2 SB 72-1577 R01, dated August 16, 2019. After 
replacement of the inserts is accomplished, the requirements of this 
AD have been met and no further action is required.
    (4) If the inserts on the HMU/MEC idler adapter pass both the 
protrusion check and the pull-out test required by paragraphs (h)(1) 
and (2) of this AD, the requirements of this AD have been met and no 
further action is required.

(i) Credit for Previous Actions

    You may take credit for the initial shim check of the HMU/MEC 
idler adapter required by paragraph (g)(1) of this AD if you 
performed this shim check before the effective date of this AD using 
GE CF6-80C2 SB 72-1577 R00, dated October 31, 2018.

(j) 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 
separation of engine flanges solely for the purposes of 
transportation of the engine without subsequent maintenance, which 
does not constitute an engine shop visit.

(k) 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 (l)(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.

(l) Related Information

    (1) For more information about this AD, contact Matthew Smith, 
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: 781-238-7735; fax: 781-238-7199; email: 
matthew.c.smith@faa.gov.
    (2) For service information identified in this AD, contact 
General Electric Company, 1 Newman Way, Cincinnati, OH 45215, United 
States; phone: (513) 552-3272; email: 
aviation.fleetsupport@ae.ge.com. You may view this referenced 
service information at the FAA, Engine & 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 on April 6, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-07565 Filed 4-9-20; 8:45 am]
 BILLING CODE 4910-13-P