Rule2026-11528
Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
June 9, 2026
Effective
July 14, 2026
Issuing agencies
Transportation DepartmentFederal Aviation Administration
Abstract
The FAA is adopting a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47E airplanes. This AD was prompted by a report of the stall warning protection system (SWPS) engaging when not appropriate. This AD requires updating operational software and incorporating a pilot's operating handbook (POH) temporary revision (TR). This AD also prohibits the installation of affected software. The FAA is issuing this AD to address the unsafe condition on these products.
Full Text
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<title>Federal Register, Volume 91 Issue 110 (Tuesday, June 9, 2026)</title>
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[Federal Register Volume 91, Number 110 (Tuesday, June 9, 2026)]
[Rules and Regulations]
[Pages 34752-34754]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-11528]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2026-2715; Project Identifier MCAI-2025-01779-A;
Amendment 39-23371; AD 2026-12-01]
RIN 2120-AA64
Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47E airplanes. This
AD was prompted by a report of the stall warning protection system
(SWPS) engaging when not appropriate. This AD requires updating
operational software and incorporating a pilot's operating handbook
(POH) temporary revision (TR). This AD also prohibits the installation
of affected software. The FAA is issuing this AD to address the unsafe
condition on these products.
DATES: This AD is effective July 14, 2026.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of July 14,
2026.
ADDRESSES:
AD Docket: You may examine the AD docket at <a href="http://regulations.gov">regulations.gov</a> under
Docket No. FAA-2026-2715; 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
address for Docket Operations is U.S. Department of Transportation,
Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200
New Jersey Avenue SE, Washington, DC 20590.
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#2a6b6e596a4f4b594b044f5f58455a4b044f5f"><span class="__cf_email__" data-cfemail="e3a2a790a386829082cd8696918c9382cd8696">[email protected]</span></a>;
website: easa.europa.eu. You may find this 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, 1100 Main, Kansas City, MO
64105. 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-2026-2715.
FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aviation Safety
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
phone: (816) 329-4059; email: <a href="/cdn-cgi/l/email-protection#52363d27357c2027363d3e223a123433337c353d24"><span class="__cf_email__" data-cfemail="7f1b100a18510d0a1b10130f173f191e1e51181009">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Background
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to certain Pilatus Model
PC-12/47E airplanes. The NPRM was published in the Federal Register on
March 19, 2026 (91 FR 13240). The NPRM was prompted by AD 2025-0271,
dated December 2, 2025 (EASA AD 2025-0271) (also referred to as the
MCAI), issued by EASA, which is the Technical Agent for the Member
States of the European Union. The MCAI states that during a test flight
on a Pilatus Model PC-12/47E airplane in which the airplane flew
specific maneuvers where gravitational loads (g-loads) were close to 0
g, during landing with flaps at 40 degrees, the SWPS triggered at a
higher-than-expected airspeed, including the aural warning, stick
shaker, and stick pusher. This same software is on the delivered
airplanes that are affected by this AD. This condition, if not
addressed, could result in reduced safety margins of the airplane,
increased pilot workload, and reduced control of the airplane.
In the NPRM, the FAA proposed to require updating operational
software and incorporating a POH TR. The NPRM also proposed to prohibit
the installation of affected software, as specified in EASA AD 2025-
0271. The FAA is issuing this AD to address the unsafe condition on
these products.
You may examine the MCAI in the AD docket at <a href="http://regulations.gov">regulations.gov</a> under
Docket No. FAA-2026-2715.
Discussion of Final Airworthiness Directive
Comments
The FAA received no comments on the NPRM or on the determination of
the costs.
Conclusion
These products have been approved by the civil aviation authority
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 reviewed the relevant
data, considered any comments received, and determined that air safety
requires adopting this AD as proposed. Accordingly, the FAA is issuing
this AD to address the unsafe condition on these products. This AD is
adopted as proposed in the NPRM.
Material Incorporated by Reference Under 1 CFR Part 51
The FAA reviewed EASA AD 2025-0271, which specifies procedures for
updating the Honeywell Primus APEX operational software, and for
incorporating Pilatus PC-12/47E POH TR No. 32 into the POH. EASA AD
2025-0271 also allows for the incorporation of a later POH revision
that includes the same POH amendment content and prohibits the
installation of affected software. 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.
Costs of Compliance
The FAA estimates that this AD affects 265 airplanes of U. S.
registry.
The FAA estimates the following costs to comply with this AD:
[[Page 34753]]
Estimated Costs
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Cost per Cost on U.S.
Action Labor cost Parts cost product operators
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Update software........................... 3 work-hours x $85 per hour = $0 $255 $67,575
$255.
Revise POH................................ 1 work-hour x $85 per hour = 0 85 22,525
$85.
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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,
(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:
2026-12-01 Pilatus Aircraft Ltd.: Amendment 39-23371; Docket No.
FAA-2026-2715; Project Identifier MCAI-2025-01779-A.
(a) Effective Date
This airworthiness directive (AD) is effective July 14, 2026.
(b) Affected ADs
None.
(c) Applicability
This AD applies to Pilatus Aircraft Ltd. Model PC-12/47E
airplanes, manufacturer serial numbers 1720 and 2001 through 2476,
certificated in any category.
(d) Subject
Joint Aircraft System Component (JASC) Code 4500, Central
Maint., Computer.
(e) Unsafe Condition
This AD was prompted by a report of the stall warning protection
system (SWPS) engaging when not appropriate. The FAA is issuing this
AD to ensure the update of the certified operational software and
prevent the inappropriate activation of the SWPS. The unsafe
condition, if not addressed, could result in reduced safety margins
of the airplane, increased pilot workload, and reduced control of
the airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Actions
(1) 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, European Union Aviation Safety Agency (EASA)
AD 2025-0271, dated December 2, 2025 (EASA AD 2025-0271).
(2) The owner/operator (pilot) holding at least a private pilot
certificate may revise the existing pilot's operating handbook (POH)
for the airplane and must enter compliance with this requirement
into the aircraft records in accordance with 14 CFR 43.9(a) and
91.417(a)(2)(v). The record must be maintained as required by 14 CFR
91.417, 121.380, or 135.439.
(h) Exceptions to EASA AD 2025-0271
(1) Where EASA AD 2025-0271 refers to its effective date, this
AD requires using the effective date of this AD.
(2) Where paragraph (4) of EASA AD 2025-0271 specifies to
``Implement the instructions of the POH TR as required by paragraph
(4.1) or (4.2) of this AD, as applicable'', this AD requires
replacing that text with ``revise the Emergency Procedures section
and Airplane and Systems Description section of the existing POH for
the airplane by inserting a copy of the POH TR [Temporary Revision]
as defined in EASA AD 2025-0271''.
(3) This AD does not adopt the ``Remarks'' section of EASA AD
2025-0271.
(i) No Reporting Requirement
Although the service material referenced in EASA AD 2025-0271
specifies to submit certain information to the manufacturer, this AD
does not include those requirements.
(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#9cddd1d3dfdcfafdfdb2fbf3ea"><span class="__cf_email__" data-cfemail="abeae6e4e8ebcdcaca85ccc4dd">[email protected]</span></a>.
(2) Before using any approved AMOC, notify your appropriate
principal inspector, or lacking a principal inspector, the manager
of the responsible flight standards district office/certificate
holding district office.
(k) Additional Information
For more information about this AD, contact Doug Rudolph,
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410,
Westbury, NY 11590; phone: (816) 329-4059; email:
<a href="/cdn-cgi/l/email-protection#32565d47551c4047565d5e425a725453531c555d44"><span class="__cf_email__" data-cfemail="4d2922382a633f382922213d250d2b2c2c632a223b">[email 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.
[[Page 34754]]
(i) European Union Aviation Safety Agency (EASA) AD 2025-0271,
dated December 2, 2025.
(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#1253566152777361733c7767607d62733c7767"><span class="__cf_email__" data-cfemail="b2f3f6c1f2d7d3c1d39cd7c7c0ddc2d39cd7c7">[email protected]</span></a>; website: easa.europa.eu. You may
find this EASA AD on the EASA website at ad.easa.europa.eu.
(4) You may view this material at the FAA, Airworthiness
Products Section, Operational Safety Branch, 1100 Main, Kansas City,
MO 64105. 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#93f5e1bdfafde0e3f6f0e7fafcfdd3fdf2e1f2bdf4fce5"><span class="__cf_email__" data-cfemail="e98f9bc780879a998c8a9d808687a987889b88c78e869f">[email protected]</span></a>.
Issued on June 2, 2026.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft
Certification Service.
[FR Doc. 2026-11528 Filed 6-8-26; 8:45 am]
BILLING CODE 4910-13-P
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