Document ID: FAA-2019-0597-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: CFM International S.A. Turbofan Engines
Posted Date: 2019-10-23T04:00Z

[Federal Register Volume 84, Number 205 (Wednesday, October 23, 2019)]
[Proposed Rules]
[Pages 56709-56712]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-23089]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0597; Product Identifier 2019-NE-05-AD]
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) 
2019-12-05, which applies to certain CFM International S.A. (CFM) 
CFM56-5B, CFM56-5C, and CFM56-7B model turbofan engines with a certain 
rotating air high-pressure turbine (HPT) front seal. AD 2019-12-05 
requires replacement of the affected rotating air HPT front seal with a 
part eligible for

[[Page 56710]]

installation. The actions required by AD 2019-12-05 are interim and 
only address the highest risk engines with an affected rotating air HPT 
front seal that have a specified number of cycles since being 
reconfigured. This proposed AD would require removal and replacement of 
the rotating air HPT front seals installed on all CFM CFM56-5B, CFM56-
5C, and CFM56-7B model turbofan engines, including engines that have 
fewer cycles since being reconfigured. 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 December 9, 
2019.

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 http://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 Inc., Aviation Operations Center, 1 Neumann Way, M/D Room 
285, Cincinnati, OH, 45125; phone: 877-432-3272; fax: 877-432-3329; 
email: aviation.fleetsupport@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 http://www.regulations.gov by searching for and locating Docket No. FAA-2019-
0597; 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: Christopher McGuire, Aerospace 
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; 
phone: 781-238-7120; fax: 781-238-7199; email: chris.mcguire@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-2019-0597; 
Product Identifier 2019-NE-05-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 http://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 2019-12-05, Amendment 39-19660 (84 FR 28717, June 
20, 2019), (``AD 2019-12-05''), for all CFM CFM56-5B, CFM56-5C, and 
CFM56-7B model turbofan engines with a certain rotating air HPT front 
seal. AD 2019-12-05 requires replacement of the affected rotating air 
HPT front seal with a part eligible for installation. AD 2019-12-05 
resulted from cracks found in the rotating air HPT front seal. The FAA 
issued AD 2019-12-05 to prevent failure of the rotating air HPT front 
seal.

Actions Since AD 2019-12-05 Was Issued

    The actions required by AD 2019-12-05 are interim and only address 
the highest risk engines with an affected rotating air HPT front seal 
that have a specified number of cycles since being reconfigured. The 
FAA now proposes to supersede AD 2019-12-05 to require removal and 
replacement of the rotating air HPT front seals installed on all CFM 
CFM56-5B, CFM56-5C, and CFM56-7B model turbofan engines, including 
engines that have fewer cycles since being reconfigured.

Related Service Information

    The FAA reviewed CFM Service Bulletin (SB) CFM56-5B S/B 72-1074, 
Revision 01, dated December 5, 2018; CFM SB CFM56-5C S/B 72-0794, 
Revision 01, dated January 2, 2019; and CFM SB CFM56-7B S/B 72-1042, 
Revision 01, dated January 2, 2019. CFM SB CFM56-5B S/B 72-1074, 
Revision 01, describes procedures for replacement of the affected 
rotating air HPT front seal on CFM CFM56-5B model turbofan engines. CFM 
SB CFM56-5C S/B 72-0794, Revision 01, describes procedures for 
replacement of the affected rotating air HPT front seal on CFM CFM56-5C 
model turbofan engines. CFM SB CFM56-7B S/B 72-1042, Revision 01, 
describes procedures for replacement of the affected rotating air HPT 
front seal on CFM CFM56-7B model turbofan engines.

FAA's Determination

    The FAA is proposing this AD because it 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 all requirements of AD 2019-12-05. 
This proposed AD would add CFM CFM56-5B, CFM56-5C, and CFM56-7B model 
turbofan engines to the applicability.

Costs of Compliance

    The FAA estimates that this proposed AD affects four engines 
installed on airplanes of U.S. registry.
    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
----------------------------------------------------------------------------------------------------------------
Replace the rotating air HPT front      1 work-hour x $85 per           $344,600        $344,685      $1,378,740
 seal.                                   hour = $85.
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[[Page 56711]]

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, 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) 
2019-12-05, Amendment 39-19660 (84 FR 28717, June 20, 2019), and adding 
the following new AD:

CFM International S.A.: Docket No. FAA-2019-0597; Product Identifier 
2019-NE-05-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by December 9, 
2019.

(b) Affected ADs

    This AD replaces AD 2019-12-05, Amendment 39-19660 (84 FR 28717, 
June 20, 2019).

(c) Applicability

    This AD applies to:
    (1) CFM International S.A. (CFM) CFM56-5B1, -5B2, -5B4, -5B5, -
5B6, -5B7, -5B1/P, -5B2/P, -5B3/P, -5B4/P, -5B5/P, -5B6/P, -5B7/P, -
5B8/P, -5B9/P, -5B3/P1, -5B4/P1, -5B1/2P, -5B2/2P, -5B3/2P, -5B4/2P, 
-5B6/2P, -5B9/2P, -5B3/2P1, -5B4/2P1, -7B20, -7B22, -7B24, -7B26, -
7B27, -7B22/B1, -7B24/B1, -7B26/B1, -7B26/B2, -7B27/B1, -7B27/B3, -
7B20/2, -7B22/2, -7B24/2, -7B26/2, -7B27/2, -7B27A model turbofan 
engines with a:
    (i) Rotating air high-pressure turbine (HPT) front seal:
    (A) With part number (P/N) 1795M36P01 or P/N 1795M36P02 and 
serial numbers (S/Ns) GWNDN949 through GWNSE969 or S/Ns GWN000CE 
through GWN0990L, not including S/Ns GWN08ND7, GWN0923A, GWN0971E, 
GWN098A1, GWN098W6, GWN098W8, GWN098WA, and GWN0990G, installed;
    (B) that has been removed from the original HPT disk and re-
assembled to a different HPT disk.
    (ii) [Reserved]
    (2) CFM CFM56-5C2, -5C2/4, -5C2/F, -5C2/F4, -5C2/G, -5C2/G4, -
5C2/P, -5C3/F, -5C3/F4, -5C3/G, -5C3/G4, -5C3/P, -5C4, -5C4/1, -5C4/
P, -5C4/1P model turbofan engines with a:
    (i) Rotating air HPT front seal:
    (A) With P/N 1795M36P01 or P/N 1795M36P02 and S/Ns GWNDN949 
through GWNSE969 or S/Ns GWN000CE through GWN0990L, not including S/
Ns GWN08ND7, GWN0923A, GWN0971E, GWN098A1, GWN098W6, GWN098W8, 
GWN098WA, and GWN0990G, installed;
    (B) that has been removed from the original HPT disk and re-
assembled to a different HPT disk.
    (ii) [Reserved]

(d) Subject

    Joint Aircraft System Component (JASC) Code 7250, Turbine 
Section.

(e) Unsafe Condition

    This AD was prompted by cracks found in the rotating air HPT 
front seal. The FAA is issuing this AD to prevent failure of the 
rotating air HPT front seal. The unsafe condition, if not addressed, 
could result in the uncontained release of the rotating air HPT 
front seal, damage to the engine, and damage to the airplane.

(f) Compliance

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

(g) Required Actions

    (1) For all affected CFM CFM56-5B and CFM56-7B model turbofan 
engines:
    (i) If, on July 5, 2019 (the effective date of AD 2019-12-05), 
the rotating air HPT front seal has 7,000 cycles or greater since 
being reconfigured, remove the part from service within 50 cycles 
after July 5, 2019 (the effective date of AD 2019-12-05), or before 
further flight, whichever occurs later, and replace with a part 
eligible for installation.
    (ii) If, on July 5, 2019 (the effective date of 2019-12-05), the 
rotating air HPT front seal has between 6,001 and 6,999 cycles, 
inclusive, since being reconfigured, remove the part from service 
within 500 cycles after July 5, 2019 (the effective date of AD 2019-
12-05), but not to exceed 7,050 cycles since being reconfigured, or 
before further flight, whichever occurs later, and replace with a 
part eligible for installation.
    (iii) For all remaining CFM56-5B and CFM56-7B model turbofan 
engines, remove the rotating air HPT front seal from service before 
accumulating 6,500 cycles since being reconfigured, or within 50 
cycles after the effective date of this AD, whichever occurs later.
    (2) For all affected CFM CFM56-5C model turbofan engines:
    (i) If, on July 5, 2019 (the effective date of AD 2019-12-05), 
the rotating air HPT front seal has 4,250 cycles or greater since 
being reconfigured, remove the part from service within 25 cycles 
after July 5, 2019 (the effective date of AD 2019-12-05), within 
1,500 cycles since the last fluorescent penetrant inspection (FPI) 
of the rotating air HPT front seal, or before further flight after 
the effective date of this AD, whichever occurs later, and replace 
with a part eligible for installation.
    (ii) If, on July 5, 2019 (the effective date of AD 2019-12-05), 
the rotating air HPT front seal has between 3,751 and 4,249 cycles, 
inclusive, since being reconfigured, remove the part from service 
within 250 cycles after July 5, 2019 (the effective date of AD 2019-
12-05), before accumulating 4,275 cycles since being reconfigured, 
within 1,500 cycles since the last FPI of the rotating air HPT front 
seal, or before further flight after the effective date of this AD, 
whichever occurs later, and replace with a part eligible for 
installation.
    (iii) For all remaining CFM CFM56-5C model turbofan engines, 
remove the rotating

[[Page 56712]]

air HPT front seal from service before accumulating 4,000 cycles 
since being reconfigured, or within 50 cycles after the effective 
date of this AD, whichever occurs later.

(h) Definition

    For the purpose of this AD, ``reconfigured'' occurs when a 
rotating air HPT front seal has been removed from the original HPT 
disk and re-assembled to a different HPT disk.

(i) Installation Prohibition

    After the effective date of this AD, do not assemble any 
rotating air HPT front seal with greater than 0 cycles since new 
onto a HPT disk unless it is the same S/N HPT disk on which it has 
previously been assembled.

(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 
39.19. 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 (k)(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.

(k) Related Information

    (1) For more information about this AD, contact Christopher 
McGuire, Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: 781-238-7120; fax: 781-238-7199; email: 
chris.mcguire@faa.gov.
    (2) For service information identified in this AD, contact CFM 
International Inc., Aviation Operations Center, 1 Neumann Way, M/D 
Room 285, Cincinnati, OH 45125; phone: 877-432-3272; fax: 877-432-
3329; email: aviation.fleetsupport@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 in Burlington, Massachusetts, on October 18, 2019.
Robert J. Ganley,
Manager, Engine and Propeller Standards Branch, Aircraft Certification 
Service.
[FR Doc. 2019-23089 Filed 10-22-19; 8:45 am]
 BILLING CODE 4910-13-P