Airworthiness Directives; Leonardo S.p.a. Helicopters

Issuing agencies

Abstract

The FAA is adopting a new airworthiness directive (AD) for certain Leonardo S.p.a. Model AB139 and AW139 helicopters. This AD was prompted by a report of a nozzle exhaust duct clamp separating from the engine nozzle duct and coming to rest on the tail rotor (TR) drive shaft. This AD requires repetitively inspecting certain clamp assemblies and, depending on the results of the inspection, replacing parts. This AD also prohibits the installation of an affected clamp assembly, unless certain requirements are met. The FAA is issuing this AD to address the unsafe condition on these products.

Full Text

<html>
<head>
<title>Federal Register, Volume 91 Issue 189 (Thursday, October 1, 2026)</title>
</head>
<body><pre>
[Federal Register Volume 91, Number 189 (Thursday, October 1, 2026)]
[Rules and Regulations]
[Pages 62301-62304]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-20100]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2026-11789; Project Identifier MCAI-2026-00908-R; 
Amendment 39-23480; AD 2026-20-07]
RIN 2120-AA64


Airworthiness Directives; Leonardo S.p.a. Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain Leonardo S.p.a. Model AB139 and AW139 helicopters. This AD was 
prompted by a report of a nozzle exhaust duct clamp separating from the 
engine nozzle duct and coming to rest on the tail rotor (TR) drive 
shaft. This AD requires repetitively inspecting certain clamp 
assemblies and, depending on the results of the inspection, replacing 
parts. This AD also prohibits the installation of an affected clamp 
assembly, unless certain requirements are met. The FAA is issuing this 
AD to address the unsafe condition on these products.

DATES: This AD is effective October 16, 2026.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of October 16, 
2026.
    The FAA must receive comments on this AD by November 16, 2026.

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://regulations.gov">regulations.gov</a>. Follow 
the instructions for submitting comments.
    <bullet> Fax: (202) 493-2251.

[[Page 62302]]

    <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: 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 <a href="http://regulations.gov">regulations.gov</a> under 
Docket No. FAA-2026-11789; 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 mandatory continuing airworthiness 
information (MCAI), any comments received, and other information. The 
street address for Docket Operations is listed above.
    Material Incorporated by Reference:
    <bullet> For European Union Aviation Safety Agency (EASA) material 
identified in this AD, contact EASA, Konrad-Adenauer-Ufer 3, 50668 
Cologne, Germany; phone: +49 221 8999 000; email: <a href="/cdn-cgi/l/email-protection#3e7f7a4d7e5b5f4d5f105b4b4c514e5f105b4b"><span class="__cf_email__" data-cfemail="b9f8fdcaf9dcd8cad897dccccbd6c9d897dccc">[email&#160;protected]</span></a>; 
website: easa.europa.eu. You may find the EASA material on the EASA 
website at ad.easa.europa.eu.
    <bullet> You may view this material at the FAA, Airworthiness 
Products Section, Operational Safety Branch, 10101 Hillwood Parkway, 
Fort Worth, TX 76177. For information on the availability of this 
material at the FAA, call (817) 222-5110. It is also available at 
<a href="http://regulations.gov">regulations.gov</a> under Docket No. FAA-2026-11789.

FOR FURTHER INFORMATION CONTACT: Evan Weaver, Aviation Safety Engineer, 
FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (316) 
944-8910; email: <a href="/cdn-cgi/l/email-protection#b5d0c3d4db9bc59bc2d0d4c3d0c7f5d3d4d49bd2dac3"><span class="__cf_email__" data-cfemail="630615020d4d134d140602150611230502024d040c15">[email&#160;protected]</span></a>.

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written data, views, or arguments 
about this final rule. Send your comments using a method listed under 
ADDRESSES. Include ``Docket No. FAA-2026-11789; Project Identifier 
MCAI-2026-00908-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 
<a href="http://regulations.gov">regulations.gov</a>, 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 Evan 
Weaver, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590. Any commentary that the FAA receives which is not 
specifically designated as CBI will be placed in the public docket for 
this rulemaking.

Background

    EASA, which is the Technical Agent for the Member States of the 
European Union, has issued EASA AD 2026-0165, dated August 18, 2026 
(EASA AD 2026-0165) (also referred to as the MCAI), to correct an 
unsafe condition on certain Leonardo S.p.a. Model AB139 and AW139 
helicopters. The MCAI states that a report was received of a nozzle 
exhaust duct clamp that became separated from its seating on the engine 
nozzle duct and then came to rest on the TR drive shaft. The FAA is 
issuing this AD to detect and address any damage to the TR drive shaft, 
which could result in loss of control of the helicopter around the yaw 
axis.
    You may examine the MCAI in the AD docket at <a href="http://regulations.gov">regulations.gov</a> under 
Docket No. FAA-2026-11789.

Material Incorporated by Reference Under 1 CFR Part 51

    The FAA reviewed EASA AD 2026-0165, which specifies procedures for 
repetitively inspecting the entire external and lateral surfaces of the 
clamp assembly for cracks and damage, and depending on the results of 
the inspection, replacing parts, reporting the results of the 
inspection, and performing further inspections. EASA AD 2026-0165 also 
prohibits the installation of an affected clamp assembly on any 
helicopter, unless certain requirements are met.
    This material 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

    These products have been approved by the civil aviation authority 
(CAA) of another country and are approved for operation in the United 
States. Pursuant to the FAA's bilateral agreement with this State of 
Design Authority, that authority has notified the FAA of the unsafe 
condition described in the MCAI referenced above. The FAA is issuing 
this AD after determining that the unsafe condition described 
previously is likely to exist or develop on other products of the same 
type design.

AD Requirements

    This AD requires accomplishing the actions specified in EASA AD 
2026-0165, described previously, as incorporated by reference, except 
for any differences identified as exceptions in the regulatory text of 
this AD.

Explanation of Required Compliance Information

    In the FAA's ongoing efforts to improve the efficiency of the AD 
process, the FAA developed a process to use some CAA ADs as the primary 
source of information for compliance with requirements for 
corresponding FAA ADs. The FAA has been coordinating this process with 
manufacturers and CAAs. As a result, EASA AD 2026-0165 is incorporated 
by reference in this AD. This AD requires compliance with EASA AD 2026-
0165 in its entirety through that incorporation, except for any 
differences identified as exceptions in the regulatory text of this AD. 
Using common terms that are the same as the heading of a particular 
section in EASA AD 2026-0165 does not mean that operators need comply 
only with that section. For example, where the AD requirement refers to 
``all required actions and compliance times,'' compliance with this AD 
requirement is not limited to the section titled ``Required Action(s) 
and Compliance Time(s)'' in EASA AD 2026-0165. Material required by 
EASA AD 2026-0165 for compliance will be available at <a href="http://regulations.gov">regulations.gov</a> 
under Docket No. FAA-2026-11789 after this AD is published.

Justification for Immediate Adoption and Determination of the Effective 
Date

    Section 553(b) of the Administrative Procedure Act (APA) (5 U.S.C. 
551 et

[[Page 62303]]

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 requires the immediate adoption of 
this AD without providing an opportunity for public comments prior to 
adoption. The FAA has found that the risk to the flying public 
justifies forgoing notice and comment prior to adoption of this rule 
because the TR drive shaft is critical to the control of a helicopter, 
and failure of the TR drive shaft could occur during any phase of 
flight without prior warning, particularly if the nozzle exhaust duct 
clamp detaches from its seating and comes into contact with the TR 
drive shaft. Additionally, the FAA has no information pertaining to the 
extent of damage on the nozzle exhaust duct clamp. If this issue is not 
addressed, it could lead to damage of the TR drive shaft, which could 
result in loss of control of the helicopter around the yaw axis. 
Furthermore, the affected parts must be inspected within 25 hours time-
in-service after the effective date of this AD. This compliance time is 
shorter than the time necessary for the public to comment and for the 
publication of the final rule. Accordingly, notice and opportunity for 
prior public comment are impracticable and contrary to the public 
interest pursuant to 5 U.S.C. 553(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 the FAA found good cause to forgo 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 the FAA has determined 
that it has good cause to adopt this rule without prior notice and 
comment, RFA analysis is not required.

Interim Action

    The FAA considers that this AD is an interim action. If further 
action is later identified, the FAA might consider further rulemaking 
then.

Costs of Compliance

    The FAA estimates that this AD affects 57 helicopters 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
----------------------------------------------------------------------------------------------------------------
Inspect clamp assemblies.................  2 work-hours x $85 per hour           $0         $170          $9,690
                                            = $170.
----------------------------------------------------------------------------------------------------------------

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

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                  Action                            Labor cost           Parts cost        Cost per product
----------------------------------------------------------------------------------------------------------------
Replace damaged clamp assembly...........  2 work-hours x $85 per hour       $2,739  $2,909 (per damaged
                                            = $170.                                   assembly).
----------------------------------------------------------------------------------------------------------------

    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some of the costs of this AD 
may be covered under warranty, thereby reducing the cost impact on 
affected operators.

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, 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.

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:


[[Page 62304]]


2026-20-07 Leonardo S.p.a.: Amendment 39-23480; Docket No. FAA-2026-
11789; Project Identifier MCAI-2026-00908-R.

(a) Effective Date

    This airworthiness directive (AD) is effective October 16, 2026.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Leonardo S.p.a. Model AB139 and AW139 
helicopters, certificated in any category, as identified in European 
Union Aviation Safety Agency AD 2026-0165, dated August 18, 2026 
(EASA AD 2026-0165).

(d) Subject

    Joint Aircraft System Component (JASC) Code 7800, Engine exhaust 
system.

(e) Unsafe Condition

    This AD was prompted by a report of a nozzle exhaust duct clamp 
separating from the engine nozzle duct and coming to rest on the 
tail rotor (TR) drive shaft, which caused damage to the TR drive 
shaft. The FAA is issuing this AD to detect and address damage to 
the TR drive shaft, which could result in loss of control of the 
helicopter around the yaw axis.

(f) Compliance

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

(g) Requirements

    Except as specified in paragraphs (h) and (i) of this AD: Comply 
with all required actions and compliance times specified in, and in 
accordance with, EASA AD 2026-0165.

(h) Exceptions to EASA AD 2026-0165

    (1) Where EASA AD 2026-0165 refers to its effective date, this 
AD requires using the effective date of this AD.
    (2) Where paragraph (1) of EASA AD 2026-0165 requires compliance 
in terms of flight hours, this AD requires using hours time-in-
service.
    (3) Where the material referenced in EASA AD 2026-0165 specifies 
``perform the detailed visual inspection for damage and crack(s)'', 
this AD requires replacing that text with ``perform the detailed 
visual inspection for physical damage including, but not limited to, 
cracks, gouges, tears, bulges, fractures, distortions, and 
creases.''
    (4) This AD does not adopt the ``Remarks'' section of EASA AD 
2026-0165.

(i) No Reporting or Returning of Parts Requirement

    Although EASA AD 2026-0165 and the material referenced in EASA 
AD 2026-0165 specifies to submit certain information and return 
parts to the manufacturer, this AD does not require those actions.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, International Validation 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 International Validation Branch, send 
it to the attention of the person identified in paragraph (k) of 
this AD and email to <a href="/cdn-cgi/l/email-protection#b7f6faf8f4f7d1d6d699d0d8c1"><span class="__cf_email__" data-cfemail="57161a18141731363679303821">[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.

(k) Additional Information

    For more information about this AD, contact Evan Weaver, 
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: (316) 944-8910; email: 
<a href="/cdn-cgi/l/email-protection#5e3b283f30702e70293b3f283b2c1e383f3f70393128"><span class="__cf_email__" data-cfemail="6a0f1c0b04441a441d0f0b1c0f182a0c0b0b440d051c">[email&#160;protected]</span></a>.

(l) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference of the material listed in this paragraph 
under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this material as applicable to do the actions 
required by this AD, unless the AD specifies otherwise.
    (i) European Union Aviation Safety Agency (EASA) AD 2026-0165, 
dated August 18, 2026.
    (ii) [Reserved]
    (3) For EASA material identified in this AD, contact EASA, 
Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 8999 
000; email: <a href="/cdn-cgi/l/email-protection#0243467142676371632c6777706d72632c6777"><span class="__cf_email__" data-cfemail="6d2c291e2d080c1e0c4308181f021d0c430818">[email&#160;protected]</span></a>; website: easa.europa.eu. You may 
find the EASA material on the EASA website at ad.easa.europa.eu.
    (4) You may view this material at the FAA, Airworthiness 
Products Section, Operational Safety Branch, 10101 Hillwood Parkway, 
Fort Worth, TX 76177. 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 <a href="http://www.archives.gov/federal-register/cfr/ibr-locations">www.archives.gov/federal-register/cfr/ibr-locations</a> or email <a href="/cdn-cgi/l/email-protection#2442560a4d4a57544147504d4b4a644a4556450a434b52"><span class="__cf_email__" data-cfemail="c2a4b0ecabacb1b2a7a1b6abadac82aca3b0a3eca5adb4">[email&#160;protected]</span></a>.

    Issued on September 24, 2026.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2026-20100 Filed 9-30-26; 8:45 am]
BILLING CODE 4910-13-P


</pre><script data-cfasync="false" src="/cdn-cgi/scripts/5c5dd728/cloudflare-static/email-decode.min.js"></script></body>
</html>