[Federal Register Volume 89, Number 52 (Friday, March 15, 2024)]
[Rules and Regulations]
[Pages 18771-18774]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-05547]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-0465; Project Identifier AD-2024-00139-E,R; 
Amendment 39-22702; AD 2024-05-51]
RIN 2120-AA64


Airworthiness Directives; General Electric Company Engines, and 
Various Restricted Category Rotorcraft

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain General Electric Company (GE) Model CT7-2E1, CT7-2F1, CT7-8A, 
CT7-8E, CT7-8F5 engines, and various restricted category helicopters 
with GE Model T700-GE-700,-701A, -701C, -701D/CC, -701D, -401, -401C, 
CT7-2D or CT7-2D1 engines installed. This AD was prompted by at least 
four reports of failures of the torque reference tube magnetic insert 
braze joint of the power turbine drive shaft assembly within the last 
several months. This AD requires a phase array ultrasonic inspection of 
the torque reference tube magnetic insert braze joint of the power 
turbine drive shaft assembly for inadequate braze coverage, and repair 
or replacement of the power turbine drive shaft assembly if necessary. 
The FAA previously sent an emergency AD to all known U.S. owners and 
operators of these engines and helicopters and is now issuing this AD 
to address the unsafe condition on these products.

DATES: This AD is effective April 1, 2024. Emergency AD 2024-05-51, 
issued on February 28, 2024, which contained the requirements of this 
amendment, was effective with actual notice.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications identified in this AD as of April 1, 
2024.
    The FAA must receive comments on this AD by April 29, 2024.

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 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.
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2024-0465; 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, any comments received, and other 
information. The street address for Docket Operations is listed above.
    Material Incorporated by Reference:
     For service information that is incorporated by reference, 
contact General Electric Company, 1 Neumann Way, Cincinnati, OH 45215; 
phone: (513) 552-3272; email: ge.com">aviation.fleetsupport@ge.com; website: 
ge.com.
     You may view this service information that is incorporated 
by reference 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. It is also available at regulations.gov under Docket No. FAA-
2024-0465.

FOR FURTHER INFORMATION CONTACT: Barbara Caufield, Aviation Safety 
Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: 
(781) 238-7146; email: [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written data, views, or arguments 
about

[[Page 18772]]

this final rule. Send your comments to an address listed under 
ADDRESSES. Include ``Docket No. FAA-2024-0465; Project Identifier AD-
2024-00139-E,R'' 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 final rule 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 
regulations.gov, including any personal information you provide. The 
agency will also post a report summarizing each substantive verbal 
contact received about this final rule.

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 AD 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 AD, 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 AD. Submissions containing CBI should be sent to Barbara 
Caufield, Aviation Safety Engineer, FAA, 2200 South 216th Street, Des 
Moines, WA 98198. Any commentary that the FAA receives which is not 
specifically designated as CBI will be placed in the public docket for 
this rulemaking.

Background

    On February 28, 2024, the FAA issued Emergency AD 2024-05-51 (also 
referred to as the emergency AD), which applies to certain GE Model 
CT7-2E1, CT7-2F1, CT7-8A, CT7-8E, CT7-8F5 engines, and various 
restricted category helicopters with GE Model T700-GE-700, -701A, -
701C, -701D/CC, -701D, -401, -401C, CT7-2D or CT7-2D1 engines 
installed. The emergency AD requires a phase array ultrasonic 
inspection of the torque reference tube magnetic insert braze joint of 
the power turbine drive shaft assembly for inadequate braze coverage, 
and repair or replacement of the power turbine drive shaft assembly if 
necessary. The FAA sent the emergency AD to all known U.S. owners and 
operators of these engines and helicopters. This action was prompted by 
at least four reports of failures of the torque reference tube magnetic 
insert braze joint of the power turbine drive shaft assembly within the 
last several months. This condition, if not addressed, could result in 
improper torque and engine speed indications, which in combination with 
specific phases of flight, could create an unacceptably high flight 
crew workload in maintaining control of the aircraft, and result in 
consequent loss of control of the aircraft.

FAA's Determination

    The FAA is issuing this AD because the agency 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.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed GE Alert Service Bulletin (ASB) CT7-2E1 S/B 72-
A0034, dated February 26, 2024, and GE ASB CT7-8 S/B 72-A0118, Revision 
01, dated February 26, 2024, which, among other actions, specify 
procedures for a phase array ultrasonic inspection of the torque 
reference tube magnetic insert braze joint of the power turbine drive 
shaft assembly for inadequate braze coverage. This service information 
also specifies repair or replacement of the power turbine drive shaft 
assembly if necessary. These documents are distinct since they apply to 
different engine models.
    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.

Other Related Service Information

    Since issuance of the emergency AD, Sikorsky Aircraft Corporation 
issued ASB 70-04-17, dated February 28, 2024. For the engines installed 
on restricted category helicopters, this ASB specifies procedures for a 
phase array ultrasonic inspection of the torque reference tube magnetic 
insert braze joint of the power turbine drive shaft assembly for 
inadequate braze coverage.

AD Requirements

    This AD requires a phase array ultrasonic inspection of the torque 
reference tube magnetic insert braze joint of the power turbine drive 
shaft assembly for inadequate braze coverage, and repair or replacement 
of the power turbine drive shaft assembly if necessary.

Interim Action

    The FAA considers this AD to be an interim action. The manufacturer 
is currently investigating the root cause of the unsafe condition 
identified in this AD. If final action is later identified, the FAA 
might consider further rulemaking.

Justification for Immediate Adoption and Determination of the Effective 
Date

    Section 553(b)(3)(B) of the Administrative Procedure Act (APA) (5 
U.S.C. 551 et seq.) authorizes agencies to dispense with notice and 
comment procedures for rules when the agency, for ``good cause,'' finds 
that those procedures are ``impracticable, unnecessary, or contrary to 
the public interest.'' Under this section, an agency, upon finding good 
cause, may issue a final rule without providing notice and seeking 
comment prior to issuance. Further, section 553(d) of the APA 
authorizes agencies to make rules effective in less than thirty days, 
upon a finding of good cause.
    An unsafe condition exists that required the immediate adoption of 
Emergency AD 2024-05-51, issued on February 28, 2024, to all known U.S. 
owners and operators of these engines and helicopters. The FAA found 
that the risk to the flying public justified waiving notice and comment 
prior to adoption of this rule because failure of the torque reference 
tube magnetic insert braze joint of the power turbine drive shaft 
assembly could result in improper torque and engine speed indications, 
which in combination with specific phases of flight, could create an 
unacceptably high flight crew workload in maintaining control of the 
aircraft, and result in consequent loss of control of the aircraft. 
Since this condition happens rapidly and without warning, the 
inspection and any necessary repair or replacement must be accomplished 
before further flight. Thus, the FAA has determined that the affected 
torque reference tube magnetic insert braze joint of the power turbine 
drive shaft assembly must be inspected, and repaired or replaced if 
necessary, before further flight. These conditions still exist, 
therefore, notice and opportunity for prior public comment are 
impracticable and contrary to the public interest pursuant to 5 U.S.C. 
553(b)(3)(B).
    In addition, the FAA finds that good cause exists pursuant to 5 
U.S.C. 553(d) for making this amendment effective in less than 30 days, 
for the same reasons

[[Page 18773]]

the FAA found good cause to forego notice and comment.

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 FAA has determined 
that it has good cause to adopt this rule without prior notice and 
comment, RFA analysis is not required.

Costs of Compliance

    The FAA estimates that this AD affects 100 engines installed on 
aircraft 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
----------------------------------------------------------------------------------------------------------------
Phase array ultrasonic inspection.....  1 work-hours x $85 per                $0             $85          $8,500
                                         hour = $85.
----------------------------------------------------------------------------------------------------------------

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

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Repair or replacement of the power turbine      8 work-hours x $85 per hour =            $50,000         $50,680
 drive shaft assembly.                           $680.
----------------------------------------------------------------------------------------------------------------

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

    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,
    (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 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:

2024-05-51 General Electric Company Engines, and Various Restricted 
Category Rotorcraft: Amendment 39-22702; Docket No. FAA-2024-0465; 
Project Identifier AD-2024-00139-E,R.

(a) Effective Date

    The FAA issued Emergency Airworthiness Directive (AD) 2024-05-
51, on February 28, 2024, and was sent directly to affected owners 
and operators. As a result of such actual notice, that AD was 
effective for those owners and operators on the date it was 
received. This AD contains the same requirements as that emergency 
AD and, for those who did not receive actual notice, is effective on 
April 1, 2024.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to the following products:
    (1) General Electric Company (GE) Model CT7-2E1, CT7-2F1, CT7-
8A, CT7-8E, CT7-8F5 engines, with any power turbine (PT) drive shaft 
assembly part number 5123T91G01, 5123T91G02, and 5128T51G01 
installed, and the following conditions:
    (i) A PT drive shaft assembly with less than 100 hours-time 
since new (TSN) or 100 hours-time since replacement (TSR) of the 
torque reference tube, as applicable, as of the effective date of 
this AD; and
    (ii) An engine serial number, PT module serial number, or PT 
shaft assembly serial number listed in GE Alert Service Bulletin 
(ASB) CT7-2E1 S/B 72-A0034, dated February 26, 2024 (CT7-2E1 S/B 72-
A0034); or GE ASB CT7-8 S/B 72-A0118, Revision 01, dated February 
26, 2024 (CT7-8 S/B 72-A0118, Revision 01).
    (2) Restricted category helicopters specified in paragraphs 
(c)(2)(i) through (ix) of this AD, with GE Model T700-GE-700, -701A, 
-701C, -701D/CC, -701D, -401, -401C, CT7-2D or CT7-2D1 engines 
installed, with a PT drive shaft assembly that was installed in the 
engine after January 1, 2020 and has less than 100 hours-TSN or 100 
hours-TSR, as applicable. PT drive shaft assemblies manufactured or 
repaired after January 1, 2024 are not affected by this AD.
    (i) Model EH-60A helicopters; current type certificate holders 
include, but are not limited to, Delta Enterprise; Heliqwest 
International Inc.; Pickering Aviation, Inc.; and Sixtyhawk TC, LLC.
    (ii) Model HH-60L helicopters; current type certificate holders 
include, but are not

[[Page 18774]]

limited to, Capitol Helicopters Inc.; Central Copters Inc.; and 
Sixtyhawk TC, LLC.
    (iii) Model S-70 helicopters; current type certificate holders 
include, but are not limited to, Sikorsky Aircraft Corporation.
    (iv) Model S-70A helicopters; current type certificate holders 
include, but are not limited to, Sikorsky Aircraft Corporation.
    (v) Model S-70C helicopters; current type certificate holders 
include, but are not limited to, Sikorsky Aircraft Corporation.
    (vi) Model S-70C(M) helicopters; current type certificate 
holders include, but are not limited to, Sikorsky Aircraft 
Corporation.
    (vii) Model S-70C(M1) helicopters; current type certificate 
holders include, but are not limited to, Sikorsky Aircraft 
Corporation.
    (viii) Model S-70M helicopters; current type certificate holders 
include, but are not limited to, Sikorsky Aircraft Corporation.
    (ix) Model UH-60A helicopters; current type certificate holders 
include, but are not limited to, ACE Aeronautics LLC; Billings 
Flying Service, Inc; Blackhawk Mission Equipment; Capitol 
Helicopters Inc.; Carson Helicopters; Delta Enterprise; Heliqwest 
International Inc.; High Performance Helicopters Corp.; Northwest 
Rotorcraft, LLC; Pickering Aviation, Inc.; PJ Helicopters Inc; 
Reeder Flying Service Inc.; Sixtyhawk TC, LLC; Skydance Blackhawk 
Operations LLC; Timberline Helicopters, Inc.; and Unical Air Inc.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7200, Engine 
(Turbine/Turboprop); 7250, Turbine Section.

(e) Unsafe Condition

    This AD was prompted by at least four reports of failures of the 
torque reference tube magnetic insert braze joint of the power 
turbine drive shaft assembly within the last several months. The FAA 
is issuing this AD to prevent failure of the power turbine drive 
shaft reference torque tube magnetic insert braze joint. The unsafe 
condition, if not addressed, could result in improper torque and 
engine speed indications, which in combination with specific phases 
of flight, could create an unacceptably high flight crew workload in 
maintaining control of the aircraft, and result in consequent loss 
of control of the aircraft.

(f) Compliance

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

(g) Required Actions

    (1) For GE Model CT7-2E1, CT7-2F1, CT7-8A, CT7-8E, CT7-8F5 
engines: Before further flight, do a phase array ultrasonic 
inspection of the torque reference tube magnetic insert braze joint 
of the power turbine drive shaft assembly for inadequate braze 
coverage in accordance with the Accomplishment Instructions, 
paragraph 3.A.(2) of CT7-2E1 S/B 72-A0034, or CT7-8 S/B 72-A0118, 
Revision 01, as applicable.
    (2) For engines installed on the restricted category aircraft 
specified in paragraphs (c)(2)(i) through (ix) of this AD: Before 
further flight, do a phase array ultrasonic inspection of the torque 
reference tube magnetic insert braze joint of the power turbine 
drive shaft assembly for inadequate braze coverage using a method 
approved by the Manager, AIR-520 Continued Operational Safety 
Branch, FAA.
    (3) If during any inspection required by paragraphs (g)(1) or 
(2) of this AD, any braze coverage of the torque reference tube 
magnetic insert braze joint is found to be less than 42 percent, 
before further flight, repair or replace the power turbine drive 
shaft assembly.

(h) Special Flight Permit

    A special flight permit may be issued in accordance with 14 CFR 
21.197 and 21.199 to operate the aircraft to a location where the 
phase array ultrasonic inspection can be performed, provided no 
passengers are onboard.

(i) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, AIR-520 Continued Operational Safety 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 AIR-520 Continued 
Operational Safety Branch, send it to the attention of the person 
identified in paragraph (j) of this AD and email 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.

(j) Additional Information

    For more information about this AD, contact Barbara Caufield, 
Aviation Safety Engineer, FAA, 2200 South 216th Street, Des Moines, 
WA 98198; phone: (781) 238-7146; email: [email protected].

(k) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) General Electric Company (GE) Alert Service Bulletin (ASB) 
CT7-2E1 S/B 72-A0034, dated February 26, 2024.
    (ii) GE ASB CT7-8 S/B 72-A0118, Revision 01, dated February 26, 
2024.
    (3) For service information that is incorporated by reference, 
contact General Electric Company, 1 Neumann Way, Cincinnati, OH 
45215; phone: (513) 552-3272; email: ge.com">aviation.fleetsupport@ge.com; 
website: ge.com.
    (4) You may view this service information that is incorporated 
by reference 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.
    (5) You may view this material at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email [email protected].

    Issued on March 8, 2024.
Victor Wicklund,
Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2024-05547 Filed 3-12-24; 11:15 am]
BILLING CODE 4910-13-P