[Federal Register Volume 86, Number 226 (Monday, November 29, 2021)]
[Proposed Rules]
[Pages 67669-67671]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-25870]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-1016; Project Identifier AD-2021-00625-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) Passport 20-17BB1A, Passport 20-
18BB1A, and Passport 20-19BB1A model turbofan engines. This proposed AD 
was prompted by a report of a manufacturing quality escape that 
requires a reduction to the life limit of certain high-pressure turbine 
(HPT) rotor stage 1 disks. This proposed AD would require revising the 
Airworthiness Limitations section (ALS) of the GE Passport 20 Line 
Maintenance Manual and the operator's existing approved continuous 
airworthiness maintenance program (CAMP) to incorporate a reduced life 
limit for certain HPT rotor stage 1 disks. 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 January 13, 
2022.

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

[[Page 67670]]

Company, 1 Neumann Way, Cincinnati, OH 45215; phone: (513) 552-3272; 
email: [email protected]; website: www.ge.com. 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 
(817) 222-5110.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-1016; 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: Scott Stevenson, Aviation Safety 
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; 
phone: (781) 238-7132; 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 proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2021-1016; Project Identifier 
AD-2021-00625-E'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the proposal, 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 proposal 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 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 Scott 
Stevenson, 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 received a report from GE of a manufacturing quality escape 
that identified a certain population of HPT rotor stage 1 disks that 
did not meet the design specification. GE determined that machining and 
inspection of the affected HPT rotor stage 1 disks was inconsistent 
with the engineering drawing. Further analysis by GE determined that 
the nonconformance at the forward and aft hooks of the HPT rotor stage 
1 disks may cause the disks to fail prematurely and, therefore, the 
life limit of the affected HPT rotor stage 1 disks require reduction. 
As a result, GE decreased the life limit of the affected HPT rotor 
stage 1 disks. This condition, if not addressed, could result in 
uncontained disk release, damage to the engine, and damage to the 
airplane.

FAA's Determination

    The FAA is issuing this NPRM after determining that the unsafe 
condition described previously is likely to exist or develop on other 
products of the same type design.

Related Service Information

    The FAA reviewed GE Service Bulletin PASSPORT20-A-72-00-0116-00A-
930A-D, Issue 002, dated July 22, 2021. This service information 
describes procedures for removing a certain population of HPT rotor 
stage 1 disks from service and provides serial numbers of the affected 
HPT rotor stage 1 disks.

Proposed AD Requirements in This NPRM

    This proposed AD would require revising the ALS of the GE Passport 
20 Line Maintenance Manual, GEK 112062, and the operator's existing 
approved CAMP to incorporate a reduced life limit for certain HPT rotor 
stage 1 disks.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 78 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
----------------------------------------------------------------------------------------------------------------
Revise the ALS of the Line Maintenance  1 work-hour x $85 per                 $0             $85          $6,630
 Manual and the operator's existing      hour = $85.
 approved CAMP.
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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

[[Page 67671]]

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) 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 adding the following new airworthiness 
directive:

General Electric Company: Docket No. FAA-2021-1016; Project 
Identifier AD-2021-00625-E.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by January 13, 2022.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to General Electric Company (GE) Passport 20-
17BB1A, Passport 20-18BB1A, and Passport 20-19BB1A model turbofan 
engines.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by a manufacturing quality escape that 
requires a reduction to the life limit for certain HPT rotor stage 1 
disks. The FAA is issuing this AD to prevent failure of the HPT 
rotor stage 1 disk. The unsafe condition, if not addressed, could 
result in uncontained disk release, 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 Action

    Within 120 days after the effective date of this AD, revise the 
airworthiness limitations section of the existing maintenance manual 
for your engine and the operator's existing approved continuous 
airworthiness maintenance program by adding Figure 1 to paragraph 
(g) of this AD.
[GRAPHIC] [TIFF OMITTED] TP29NO21.007

    Note 1 to paragraph (g): Where Figure 1 to paragraph (g) refers 
to ``Life Cycles,'' for the purpose of this AD, this refers to life 
cycles since new.

(h) 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 (i)(1) of this AD. Information may be 
emailed 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.

(i) Related Information

    (1) For more information about this AD, contact Scott Stevenson, 
Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: (781) 238-7132; fax: (781) 238-7199; 
email: [email protected].
    (2) For service information identified in this AD, contact 
General Electric Company, 1 Neumann Way, Cincinnati, OH 45215; 
phone: (513) 552-3272; email: [email protected]; website: 
www.ge.com. 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 (817) 222-5110.

    Issued on November 22, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-25870 Filed 11-26-21; 8:45 am]
BILLING CODE 4910-13-P