Document ID: FAA-2019-0568-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: CFM International S.A. Turbofan Engines
Posted Date: 2019-09-20T04:00Z

[Federal Register Volume 84, Number 183 (Friday, September 20, 2019)]
[Proposed Rules]
[Pages 49487-49490]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-20054]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0568; Product Identifier 2019-NE-20-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 adopt a new airworthiness directive (AD) 
for all CFM International, S.A. (CFM) CFM56-5B and CFM56-7B model 
turbofan engines with a certain high-pressure turbine (HPT) inner 
stationary seal installed. This proposed AD was prompted by cracks 
found in the rotating air HPT front seal. This proposed AD would 
require removal, inspection, and replacement of the affected HPT inner 
stationary seal, and depending on the findings, removal and replacement 
of the rotating air HPT front seal. 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 November 4, 
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 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 http://www.regulations.gov by searching for and locating Docket No. FAA-2019-
0568; 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:

[[Page 49488]]

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-2019-0568; 
Product Identifier 2019-NE-20-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 NPRM.

Discussion

    The FAA received a report that two cracks were discovered on a CFM 
CFM56-5B model turbofan engine rotating air HPT front seal during a 
routine engine shop visit. After investigation, CFM determined that the 
HPT inner stationary seal, part number 1808M56G01, may not have 
received the correct braze heat treat cycle at the time of the 
honeycomb replacement. As a result, the affected HPT inner stationary 
seal could lead to a localized separation of the replaced honeycomb, 
which may affect the life of the rotating air HPT front seal. This 
condition, if not addressed, could result in an uncontained release of 
the rotating air HPT front seal, damage to the engine, and damage to 
the airplane.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed CFM Service Bulletin (SB) CFM56-5B S/B 72-0952, 
dated April 23, 2019, and CFM SB CFM56-7B S/B 72-1054, dated April 23, 
2019. CFM SB CFM56-5B S/B 72-0952, dated April 23, 2019, describes 
procedures for repairing the CFM56-5B turbofan engine HPT inner 
stationary seal honeycomb. CFM SB CFM56-7B S/B 72-1054, dated April 23, 
2019, describes procedures for repairing the CFM56-7B turbofan engine 
HPT inner stationary seal honeycomb. 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 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 require removal, inspection, and replacement 
of the affected HPT inner stationary seal and, depending on the 
findings, removal and replacement of the rotating air HPT front seal 
with a part eligible for installation.

Costs of Compliance

    The FAA estimates that this proposed AD affects 210 engines 
installed on airplanes of U.S. registry. Operators have the option to 
replace or repair the affected HPT inner stationary seal. The part cost 
is for replacement with a repaired HPT inner stationary seal.
    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 HPT inner stationary seal.....  1 work-hour x $85 per             $7,910          $7,995      $1,678,950
                                         hour = $85.
Inspect HPT inner stationary seal.....  1 work-hour x $85 per                  0              85          17,850
                                         hour = $85.
----------------------------------------------------------------------------------------------------------------

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

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replace rotating air HPT front seal...........  1 work-hour x $85 per hour = $85        $344,600        $344,685
Inspect HPT rotor blade internal cavities.....  1 work-hour x $85 per hour = $85               0              85
Replace HPT rotor blade (pair)................  1 work-hour x $85 per hour = $85          31,000          31,085
Replace No. 3 ball bearing....................  1 work-hour x $85 per hour = $85          30,000          30,085
----------------------------------------------------------------------------------------------------------------

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.

[[Page 49489]]

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.

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):

CFM International, S.A.: Docket No. FAA-2019-0568; Product 
Identifier 2019-NE-20-AD.

(a) Comments Due Date

    The FAA must receive comments by November 4, 2019.

(b) Affected ADs

    None.

(c) Applicability

    (1) This AD applies to all CFM International, S.A. (CFM) CFM56-
5B1, -5B1/2P, -5B1/3, -5B1/P, -5B2, -5B2/2P, -5B2/3, -5B2/P, -5B3/
2P, -5B3/2P1, -5B3/3, -5B3/3B1, -5B3/P, -5B3/P1, -5B4, -5B4/2P, -
5B4/2P1, -5B4/3, -5B4/3B1, -5B4/P, -5B4/P1, -5B5, -5B5/3, -5B5/P, -
5B6, -5B6/2P, -5B6/3, -5B6/P, -5B7, -5B7/3, -5B7/P, -5B8/3, -5B8/P, 
-5B9/2P, -5B9/3, -5B9/P, CFM56-7B20, -7B20/2, -7B20/3, -7B20E, -
7B22, -7B22/2, -7B22/3, -7B22/3B1, -7B22/B1, -7B22E, -7B22E/B1, -
7B24, -7B24/2, -7B24/3, -7B24/3B1, -7B24/B1, -7B24E, -7B24E/B1, -
7B26, -7B26/2, -7B26/3, -7B26/3B1, -7B26/3B2, -7B26/3B2F, -7B26/3F, 
-7B26/B1, -7B26/B2, -7B26E, -7B26E/B1, -7B26E/B2, -7B26E/B2F, -
7B26E/F, -7B27, -7B27/2, -7B27/3, -7B27/3B1, -7B27/3B1F, -7B27/3B3, 
-7B27/3F, -7B27/B1, -7B27/B3, -7B27A, -7B27A/3, -7B27AE, -7B27E, -
7B27E/B1, -7B27E/B1F, -7B27E/B3, and -7B27E/F model turbofan engines 
with a high-pressure turbine (HPT) inner stationary seal, part 
number (P/N) 1808M56G01 installed that has a serial number (S/N) 
listed in Planning Information, Paragraph 1.A., Table 1, of CFM 
Service Bulletin (SB) CFM56-5B S/B 72-0952, dated April 23, 2019, or 
in Planning Information, Paragraph 1.A., Table 1, CFM SB CFM56-7B S/
B 72-1054, dated April 23, 2019, installed.
    (2) This AD does not apply to affected CFM CFM56-5B and CFM56-7B 
model turbofan engines with the affected HPT inner stationary seal 
installed if the seal has been repaired as specified in CFM56-5B 
Engine Shop Manual (ESM), 72-41-03, REPAIR 003, or CFM56-7B ESM, 72-
41-03, REPAIR 003, after the year listed in Paragraph 1.A., Table 1, 
of CFM SB CFM56-5B S/B 72-0952 dated April 23, 2019, or Paragraph 
1.A., Table 1, CFM SB CFM56-7B S/B 72-1054, dated April 23, 2019.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7230, Turbine Engine 
Compressor 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 HPT 
inner stationary seal and the rotating air HPT front seal. The 
unsafe condition, if not addressed, could result in 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) At the next engine shop visit after the effective date of 
this AD, remove the affected HPT inner stationary seal from service 
and replace with a HPT inner stationary seal (that is not listed in 
Planning Information, Paragraph 1.A., Table 1, of CFM SB CFM56-5B S/
B 72-0952, dated April 23, 2019, or in Planning Information, 
Paragraph 1.A., Table 1, CFM SB CFM56-7B S/B 72-1054, dated April 
23, 2019) or a repaired HPT inner stationary seal that is eligible 
for installation per the definition in paragraph (h)(2) of this AD.
    (2) After removing the affected HPT inner stationary seal 
required by paragraph (g)(1), inspect the removed HPT inner 
stationary seal for honeycomb separation, as defined in the 
Accomplishment Instructions, paragraph 3.C.(1), in CFM SB CFM56-5B 
S/B 72-0952, dated April 23, 2019, or in CFM SB CFM56-7B S/B 72-
1054, dated April 23, 2019.
    (3) If honeycomb separation is found during the inspection 
required by paragraph (g)(2) of this AD, before further flight:
    (i) Remove the rotating air HPT front seal from service and 
replace with a part eligible for installation.
    (ii) Inspect the HPT rotor blade internal cavities for honeycomb 
metal debris per the Accomplishment Instructions, paragraph 
3.C.(1)(a)(4), of CFM SB CFM56-5B S/B 72-0952, dated April 23, 2019, 
or CFM SB CFM56-7B S/B 72-1054, dated April 23, 2019. If honeycomb 
metal debris is found, remove the HPT rotor blade from service and 
replace with a part eligible for installation.
    (iii) Remove the No. 3 ball bearing from service and replace 
with a part eligible for installation.

(h) 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 that 
the separation of engine flanges solely for the purposes of 
transportation without subsequent maintenance does not constitute an 
engine shop visit.
    (2) For the purpose of this AD, a repaired HPT inner stationary 
seal that is eligible for installation is any HPT inner stationary 
seal, P/N 1808M56G01 and with a S/N listed in Paragraph 1.A., Table 
1, of CFM SB CFM56-5B S/B 72-0952, dated April 23, 2019, or 
Paragraph 1.A., Table 1, CFM SB CFM56-7B S/B 72-1054, dated April 
23, 2019 that has been repaired per CFM56-5B ESM, 72-41-03, REPAIR 
003, or CFM56-7B ESM, 72-41-03, REPAIR 003, after the year listed in 
Paragraph 1.A., Table 1, of CFM SB CFM56-5B S/B 72-0952, dated April 
23, 2019, or Paragraph 1.A., Table 1, CFM SB CFM56-7B S/B 72-1054, 
dated April 23, 2019.

(i) No Reporting Requirement

    The reporting requirements contained within the SBs referenced 
in paragraph (g) of this AD are not required by this AD.

(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

[[Page 49490]]

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 September 11, 2019.
Robert J. Ganley,
Manager, Engine and Propeller Standards Branch, Aircraft Certification 
Service.
[FR Doc. 2019-20054 Filed 9-19-19; 8:45 am]
 BILLING CODE 4910-13-P