[Federal Register Volume 86, Number 83 (Monday, May 3, 2021)]
[Proposed Rules]
[Pages 23301-23304]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-08747]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0259; Project Identifier AD-2020-01128-E]
RIN 2120-AA64


Airworthiness Directives; CFM International, S.A. Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede Airworthiness Directive (AD) 
2013-26-01, which applies to all CFM International, S.A. (CFM) CFM56-3 
and CFM56-7B model turbofan engines with a certain accessory gearbox 
assembly (AGB) not equipped with a handcranking pad oil dynamic seal 
assembly. AD 2013-26-01 requires an independent inspection to verify 
re-installation of the handcranking pad cover after removal of the pad 
cover for maintenance. Since the FAA issued AD 2013-26-01, a dual-
engine oil loss event occurred, prompting CFM to revise its service 
information to provide procedures for reworking and reidentifying the 
AGB. The FAA has also evaluated the requirement to install a redesigned 
handcranking pad oil dynamic seal assembly in response to the dual-
engine oil loss event. This proposed AD would continue to require 
independent inspection to verify re-installation of the AGB 
handcranking pad cover after maintenance. This proposed AD would 
require the replacement of the affected AGB as a terminating action to 
the inspection requirement. 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 June 17, 
2021.

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 CFM 
International, S.A., Aviation Operations Center, 1 Neumann Way, M/D 
Room 285, Cincinnati, OH 45125; phone: (877) 432-3272; email: 
[email protected]. 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.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0259; 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.

FOR FURTHER INFORMATION CONTACT: Christopher McGuire, Aviation Safety 
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; 
phone: (781) 238-7120; fax: (781) 238-7199; email: 
[email protected].

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 ADDRESSES. Include ``Docket No. FAA-2021-0259; Project 
Identifier AD-2020-01128-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 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://

[[Page 23302]]

www.regulations.gov, including any personal information you provide. 
The agency will also post a report summarizing each substantive verbal 
contact received about this NPRM.

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 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 
Christopher McGuire, Aviation Safety 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.

Background

    The FAA issued AD 2013-26-01, Amendment 39-17710 (78 FR 79295, 
December 30, 2013), (AD 2013-26-01), for all CFM CFM56-3 and CFM56-7B 
model turbofan engines equipped with a certain AGB not equipped with a 
handcranking pad oil dynamic assembly. AD 2013-26-01 requires an 
independent inspection to verify re-installation of the AGB 
handcranking pad cover after any maintenance involving the removal and 
reinstallation of the AGB handcranking pad cover. As an optional 
terminating action to the inspection requirements, AD 2013-26-01 
allowed the installation of an AGB that incorporates a handcranking pad 
oil dynamic seal assembly. AD 2013-26-01 resulted from 42 events of 
total loss of engine oil from CFM56 model turbofan engines while in 
flight. The FAA issued AD 2013-26-01 to prevent loss of engine oil 
while in flight, which could result in engine failure, loss of thrust 
control, and damage to the airplane.

Actions Since AD 2013-26-01 Was Issued

    Since the FAA issued AD 2013-26-01, a dual-engine oil loss event 
occurred, prompting the FAA to propose the mandatory installation of a 
redesigned handcranking pad oil dynamic seal assembly. In addition, CFM 
revised its service information to provide procedures for replacing the 
starter drive pad assembly and handcranking cover assembly and for 
reworking and reidentifying an affected AGB to a part eligible for 
installation.

FAA's Determination

    The FAA is issuing this NPRM after determining that 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 CFM International CFM56-7B Service Bulletin (SB) 
72-0879, Revision 6, dated March 1, 2018 (CFM SB 72-0879); CFM 
International SB CFM56-3 SB 72-1129, Revision 7, dated May 5, 2020 (CFM 
SB 72-1129); and CFM International SB CFM56-7B SB 72-0564 Revision 8, 
dated May 6, 2020 (CFM SB 72-0564). CFM SB 72-1129 describes procedures 
for the introduction of a new starter drive pad, new handcranking cover 
assembly, and reworking and reidentifying an AGB installed on CFM56-3 
model turbofan engines. CFM SB 72-0879 and CFM SB 72-0564 describe 
procedures for the introduction of a new starter drive pad, new 
handcranking cover, and reworking and reidentifying an AGB installed on 
CFM56-7B model turbofan engines. CFM SB 72-0879 and CFM SB 72-0564 are 
differentiated by the part numbers of the AGBs eligible for rework and 
the new part numbers by which these AGBs will be reidentified once 
rework is complete. 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.

Proposed AD Requirements in This NPRM

    This proposed AD would retain certain requirements of AD 2013-26-
01. This proposed AD would require the performance of an independent 
inspection to verify re-installation of the AGB handcranking pad cover 
after maintenance. Alternatively, this proposed AD would require the 
insertion of an independent inspection as a required inspection item in 
the approved continuous airworthiness maintenance program for the 
aircraft not later than the next time the AGB handcranking pad cover is 
removed for maintenance. This proposed AD would also remove the 
optional terminating action in AD 2013-26-01 and add a mandatory 
terminating action for certain model turbofan engines, requiring the 
removal and replacement of an affected AGB with an AGB that 
incorporates the oil dynamic seal assembly.
    For all CFM56-3B and the majority of CFM56-7B turbofan engine 
models, this proposed AD would require replacement of the AGB as a 
mandatory terminating action to the inspection requirement of this AD. 
This proposed AD does not require this terminating action for CFM56-
7B27A, CFM56-7B27A/3 and CFM56-7B27AE model turbofan engines because 
these model engines, which are installed only in military airplanes, do 
not have a replacement AGB eligible for installation.

Costs of Compliance

    The FAA estimates that this AD, as proposed, would affect 700 
engines installed on airplanes of U.S. registry. The FAA estimates that 
the majority of operators will perform the repair and reidentification 
of the AGB rather than replace the AGB with a zero hour part. For the 
purpose of this cost estimate, the FAA estimates that 95% of AGBs will 
be repaired and reidentified while 5% of AGBs will be replaced with a 
zero hour AGB.
    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
----------------------------------------------------------------------------------------------------------------
Independent Inspection................  1 work-hour x $85 per                 $0             $85         $59,500
                                         hour = $85.
Insert inspection item into aircraft    1 work-hour x $85 per                  0              85          59,500
 maintenance program.                    hour = $0.
Rework and reidentify AGB.............  4 work-hours x $85 per            12,000          12,340       8,206,100
                                         hour = $340.
Replace AGB with zero hour AGB........  4 work-hours x $85 per           526,700         527,040      18,446,400
                                         hour = $340.
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[[Page 23303]]

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 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) Would not affect intrastate aviation in Alaska, and
    (3) Would 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:
0
a. Removing airworthiness directive 2013-26-01, Amendment 39-17710 (78 
FR 79295, December 30, 2013); and
0
b. Adding the following new airworthiness directive:

CFM International, S.A.: Docket No. FAA-2021-0259; Project 
Identifier AD-2020-01128-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) action by June 17, 2021.

(b) Affected ADs

    This AD replaces AD 2013-26-01, Amendment 39-17710 (78 FR 79295, 
December 30, 2013).

(c) Applicability

    This AD applies to CFM International, S.A. CFM56-3 and CFM56-7B 
model turbofan engines equipped with an accessory gearbox (AGB) 
assembly with the following part numbers (P/Ns):
    (1) For CFM56-3, CFM56-3B, and CFM56-3C model turbofan engines, 
AGB P/N: 335-300-103-0, 335-300-105-0, 335-300-106-0, 335-300-107-0, 
335-300-108-0, 335-300-109-0, or 335-300-110-0, installed.
    (2) For CFM56-7B20, CFM56-7B20/2, CFM56-7B20/3, CFM56-7B22, 
CFM56-7B22/2, CFM56-7B22/3, CFM56-7B22/3B1, CFM56-7B22/B1, CFM56-
7B24, CFM56-7B24/2, CFM56-7B24/3, CFM56-7B24/3B1, CFM56-7B24/B1, 
CFM56-7B26, CFM56-7B26/2, CFM56-7B26/3, CFM56-7B26/3B1, CFM56-7B26/
3B2, CFM56-7B26/3B2F, CFM56-7B26/3F, CFM56-7B26/B1, CFM56-7B26/B2, 
CFM56-7B27, CFM56-7B27/2, CFM56-7B27/3, CFM56-7B27/3B1, CFM56-7B27/
3B1F, CFM56-7B27/3B3, CFM56-7B27/3F, CFM56-7B27/B1, and CFM56-7B27/
B3 model turbofan engines, AGB P/N: 340-046-503-0, 340-046-504-0, or 
340-046-505-0, installed.
    (3) For CFM56-7B27A, CFM56-7B27A/3, or CFM56-7B27AE model 
turbofan engines, AGB P/N: 340-188-601-0, 340-188-603-0, or 340-188-
605-0, installed.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7260, Turbine Engine 
Accessory Drive.

(e) Unsafe Condition

    This AD was prompted by a dual engine loss of oil event and 42 
prior events of total loss of engine oil during flight. The FAA is 
issuing this AD to prevent loss of engine oil while in flight. The 
unsafe condition, if not addressed, could result in engine failure, 
loss of thrust control, reduced control of the aircraft, and damage 
to the airplane.

(f) Compliance

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

(g) Required Actions

    (1) After the effective date of this AD, after any maintenance 
that involves removal and re-installation of the AGB handcranking 
pad cover, perform an independent inspection to verify re-
installation of the AGB handcranking pad cover; or
    (2) Prior to the next removal of the AGB handcranking pad cover 
from the engine, insert the independent inspection required by 
paragraph (g)(1) of this AD as a required inspection item in the 
existing approved continuous airworthiness maintenance program for 
the aircraft.

(h) Mandatory Terminating Action

    As a mandatory terminating action to the requirements of 
paragraph (g) of this AD:
    (1) For affected CFM56-3, CFM56-3B, and CFM56-3C model turbofan 
engines, at the next engine shop visit, or before December 31, 2026, 
whichever occurs first after the effective date of this AD, replace 
the affected AGB with a part eligible for installation.
    (2) For affected CFM56-7B model turbofan engines, except for 
CFM56-7B27A, CFM56-7B27A/3 and CFM56-7B27AE model turbofan engines, 
at the next engine shop visit, or before December 31, 2024, 
whichever occurs first after the effective date of this AD, replace 
the affected AGB with a part eligible for installation.

(i) 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 situations, which do not constitute an engine shop 
visit:
    (i) Separation of engine flanges solely for the purposes of 
transportation of the engine without subsequent maintenance.
    (ii) Separation of engine flanges solely for the purpose of 
replacing the fan or propulsor without subsequent maintenance.
    (2) For the purpose of this AD, for affected CFM56-3, CFM56-3B, 
and CFM56-3C model turbofan engines, a part eligible for 
installation is:
    (i) An AGB with a part number other than 335-300-103-0, 335-300-
105-0, 335-300-106-0, 335-300-107-0, 335-300-108-0, 335-300-109-0, 
335-300-110-0, or
    (ii) An affected AGB that has been reworked and reidentified to 
a part number eligible for installation using CFM International 
Service Bulletin (SB) CFM56-3 SB 72-1129, Revision 7, dated May 5, 
2020.
    (3) For the purpose of this AD, for affected CFM56-7B model 
turbofan engines, except for CFM56-7B27A, CFM56-7B27A/3 and CFM56-
7B27AE model turbofan engines, a part eligible for installation is:
    (i) An AGB with a part number other than 340-046-503-0, 340-046-
504-0, or 340-046-505-0, or
    (ii) An affected AGB that has been reworked and reidentified to 
a part number eligible for installation using, as applicable, CFM 
International SB CFM56-7B SB 72-0879, Revision 6, dated March 1, 
2018, or CFM International SB CFM56-7B SB 72-0564 Revision 8, dated 
May 6, 2020.

(j) 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 
39.1914. In accordance with 14 CFR 39.19, send your request to your 
principal inspector or local Flight Standards District

[[Page 23304]]

Office, as appropriate. If sending information directly to the 
manager of the certification office, send it to the attention of the 
person identified in Related Information. 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.

(k) Related Information

    (1) For more information about this AD, contact Christopher 
McGuire, Aviation Safety Engineer, ECO Branch, FAA, 1200 District 
Avenue, Burlington, MA 01803; phone: (781) 238-7120; fax: (781) 238-
7199; email: [email protected].
    (2) For service information identified in this AD, contact CFM 
International, S.A., Aviation Operations Center, 1 Neumann Way, M/D 
Room 285, Cincinnati, OH 45125; phone: (877) 432-3272; email: 
[email protected]. You may view this referenced 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.

    Issued on March 30, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-08747 Filed 4-30-21; 8:45 am]
BILLING CODE 4910-13-P