AD 2019-12-05

final rule

Airworthiness Directives; CFM International S.A. Turbofan Engines

AD Number
2019-12-05
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2019-0212
FR Citation
84 FR 28717
Technical illustration of an aircraft turbine engine assembly
Problem area Engine

Applicability

TypeManufacturerModelDetails
engine CFM International S Airworthiness Directives; CFM International S.A. Turbofan Engines

Unsafe Condition

cracks found in the rotating air HPT front seal on CFM56-5B model turbofan engines during a scheduled shop visit, resulting from variations in the geometry of the parts being mated.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

replace the affected rotating air HPT front seal with a part eligible for installation, as described in 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.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

CFM International S.A. CFM56-5B, CFM56-5C, and CFM56-7B model turbofan engines with a certain rotating air HPT front seal.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

The FAA is adopting a new airworthiness directive (AD) for 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. This AD requires replacement of the affected rotating air HPT front seal with a part eligible for installation. This AD was prompted by cracks found in the rotating air HPT front seal. The FAA is issuing this AD to address the unsafe condition on these products.

Applicability Source Text

Show captured applicability text from the source AD
(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; and
    (C) that has 6,001 or more cycles since being reconfigured.
    (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;

[[Page 28719]]

    (B) that has been removed from the original HPT disk and re-
assembled to a different HPT disk; and
    (C) that has 3,751 or more cycles since being reconfigured.
    (ii) [Reserved]

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 84, Number 119 (Thursday, June 20, 2019)]
[Rules and Regulations]
[Pages 28717-28719]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2019-13040]



========================================================================
Rules and Regulations
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains regulatory documents 
having general applicability and legal effect, most of which are keyed 
to and codified in the Code of Federal Regulations, which is published 
under 50 titles pursuant to 44 U.S.C. 1510.

The Code of Federal Regulations is sold by the Superintendent of Documents. 

========================================================================


Federal Register / Vol. 84, No. 119 / Thursday, June 20, 2019 / Rules 
and Regulations

[[Page 28717]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0212; Product Identifier 2019-NE-05-AD; Amendment 
39-19660; AD 2019-12-05]
RIN 2120-AA64


Airworthiness Directives; CFM International S.A. Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
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. This AD requires replacement of the affected 
rotating air HPT front seal with a part eligible for installation. This 
AD was prompted by cracks found in the rotating air HPT front seal. The 
FAA is issuing this AD to address the unsafe condition on these 
products.

DATES: This AD is effective July 5, 2019.
    The FAA must receive comments on this AD by August 5, 2019.

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 <a href="http://www.regulations.gov">http://www.regulations.gov</a>. 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 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: <a href="/cdn-cgi/l/email-protection#97f6e1fef6e3fef8f9b9f1fbf2f2e3e4e2e7e7f8e5e3d7f0f2b9f4f8fa"><span class="__cf_email__" data-cfemail="5332253a32273a3c3d7d353f363627202623233c21271334367d303c3e">[email&#160;protected]</span></a>. 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. It is also 
available on the internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching 
for and locating Docket No. FAA-2019-0212.

Examining the AD Docket

    You may examine the AD docket on the internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and locating Docket No. FAA-2019-
0212; 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, the regulatory evaluation, any comments received, and 
other information. The street address for the 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: <a href="/cdn-cgi/l/email-protection#aac9c2d8c3d984c7c9cddfc3d8cfeacccbcb84cdc5dc"><span class="__cf_email__" data-cfemail="92f1fae0fbe1bcfff1f5e7fbe0f7d2f4f3f3bcf5fde4">[email&#160;protected]</span></a>.

SUPPLEMENTARY INFORMATION: 

Discussion

    The FAA received reports that cracks were found in the rotating air 
HPT front seal on CFM56-5B model turbofan engines during a scheduled 
shop visit. After further analysis, CFM determined that when a single 
rotating air HPT front seal is mated to more than one HPT disk some 
seals develop microcracks. These cracks resulted from variations in the 
geometry of the parts being mated.
    This AD pertains to the highest risk engines and therefore 
addresses certain CFM CFM56-5B, CFM56-5C, and CFM56-7B model turbofan 
engines with an affected rotating air HPT front seal that has a 
specified number of cycles since being reconfigured. The FAA expects to 
propose future rulemaking for additional CFM CFM56-5B, CFM56-5C, and 
CFM56-7B model turbofan engines with this same rotating air HPT front 
seal that have fewer cycles since being reconfigured. These engines 
have the same unsafe condition as the engines affected by this AD but 
represent a lower safety risk due to the lower number of cycles since 
being reconfigured on the affected rotating air HPT front seal.
    This 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. The FAA is issuing this AD to address the 
unsafe condition on these products.

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 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 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 turbofan engines.

FAA's Determination

    The FAA is issuing 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.

AD Requirements

    This AD requires replacement of the affected rotating air HPT front 
seal with a part eligible for installation.

FAA's Justification and Determination of the Effective Date

    No domestic operators use the affected higher risk CFM CFM56-5B, 
CFM56-5C, and CFM56-7B model turbofan engines. Therefore, the FAA finds 
good cause that notice and opportunity for prior public comment

[[Page 28718]]

are impracticable. In addition, for the reason stated above, the FAA 
finds that good cause exists for making this amendment effective in 
less than 30 days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety and was not preceded by notice and an opportunity for public 
comment. However, 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-2019-
0212 and 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 final 
rule. The FAA will consider all comments received by the closing date 
and may amend this final rule because of those comments.
    The FAA will post all comments received, without change, to <a href="http://www.regulations.gov">http://www.regulations.gov</a>, including any personal information you provide. 
The FAA will also post a report summarizing each substantive verbal 
contact received about this final rule.

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 no 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
----------------------------------------------------------------------------------------------------------------
Replace the rotating air HPT front      1 work-hour x $85 per           $344,600        $344,685              $0
 seal.                                   hour = $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.
    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

    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.

Adoption of 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):

2019-12-05 CFM International S.A.: Amendment 39-19660; Docket No. 
FAA-2019-0212; Product Identifier 2019-NE-05-AD.

(a) Effective Date

    This AD is effective July 5, 2019.

(b) Affected ADs

    None.

(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; and
    (C) that has 6,001 or more cycles since being reconfigured.
    (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;

[[Page 28719]]

    (B) that has been removed from the original HPT disk and re-
assembled to a different HPT disk; and
    (C) that has 3,751 or more cycles since being reconfigured.
    (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 the effective date of this AD, the rotating air HPT 
front seal has 7,000 cycles or greater since being reconfigured, 
remove the part from service within 50 cycles after the effective 
date of this AD and replace with a part eligible for installation.
    (ii) If, on the effective date of this AD, 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 the effective date of this AD, but not to exceed 7,050 cycles 
since being reconfigured, and replace with a part eligible for 
installation.
    (2) For all affected CFM CFM56-5C model turbofan engines:
    (i) If, on the effective date of this AD, the rotating air HPT 
front seal has 4,250 cycles or greater since being reconfigured, 
remove the part from service within 25 cycles after the effective 
date of this AD, or within 1,500 cycles since the last fluorescent 
penetrant inspection (FPI) of the rotating air HPT front seal, 
whichever occurs later, and replace with a part eligible for 
installation.
    (ii) If, on the effective date of this AD, 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 the effective date of this AD, before accumulating 4,275 
cycles since being reconfigured, or within 1,500 cycles since the 
last FPI of the rotating air HPT front seal, whichever occurs later, 
and replace with a part eligible for installation.

(h) Definition

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

(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: <a href="/cdn-cgi/l/email-protection#6e2f202b432f2a432f23212d2e080f0f40090118"><span class="__cf_email__" data-cfemail="80c1cec5adc1c4adc1cdcfc3c0e6e1e1aee7eff6">[email&#160;protected]</span></a>.
    (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 Christopher McGuire, 
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: 781-238-7120; fax: 781-238-7199; email: 
<a href="/cdn-cgi/l/email-protection#32515a405b411c5f5155475b4057725453531c555d44"><span class="__cf_email__" data-cfemail="debdb6acb7adf0b3bdb9abb7acbb9eb8bfbff0b9b1a8">[email&#160;protected]</span></a>.

(k) Material Incorporated by Reference

    None.

    Issued in Burlington, Massachusetts, on June 14, 2019.
Karen M. Grant,
Acting Manager, Engine and Propeller Standards Branch, Aircraft 
Certification Service.
[FR Doc. 2019-13040 Filed 6-19-19; 8:45 am]
 BILLING CODE 4910-13-P

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