Rule2026-09521
Airworthiness Directives; Airbus Helicopters Deutschland GmbH (AHD) Helicopters
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
May 13, 2026
Effective
June 17, 2026
Issuing agencies
Transportation DepartmentFederal Aviation Administration
Abstract
The FAA is adopting a new airworthiness directive (AD) for all Airbus Helicopters Deutschland GmbH (AHD) Model MBB-BK 117 C-2 and MBB- BK 117 D-2 helicopters. This AD was prompted by a determination that a certain part-numbered standard MS18027 type hook may be subject to localized yielding in the mating threads when assembled to higher assembly torques. This AD requires modifying and re-identifying the affected part or replacing the affected part with a serviceable part. This AD also prohibits installing an affected part on any helicopter unless certain requirements are met. 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 92 (Wednesday, May 13, 2026)</title>
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[Federal Register Volume 91, Number 92 (Wednesday, May 13, 2026)]
[Rules and Regulations]
[Pages 26906-26908]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-09521]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2026-0730; Project Identifier MCAI-2025-01416-R;
Amendment 39-23329; AD 2026-09-08]
RIN 2120-AA64
Airworthiness Directives; Airbus Helicopters Deutschland GmbH
(AHD) Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all
Airbus Helicopters Deutschland GmbH (AHD) Model MBB-BK 117 C-2 and MBB-
BK 117 D-2 helicopters. This AD was prompted by a determination that a
certain part-numbered standard MS18027 type hook may be subject to
localized yielding in the mating threads when assembled to higher
assembly torques. This AD requires modifying and re-identifying the
affected part or replacing the affected part with a serviceable part.
This AD also prohibits installing an affected part on any helicopter
unless certain requirements are met. The FAA is issuing this AD to
address the unsafe condition on these products.
DATES: This AD is effective June 17, 2026.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of June 17,
2026.
ADDRESSES:
AD Docket: You may examine the AD docket at <a href="http://regulations.gov">regulations.gov</a> under
Docket No. FAA-2026-0730; 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
[[Page 26907]]
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#3475704774515547551a5141465b44551a5141"><span class="__cf_email__" data-cfemail="bbfaffc8fbdedac8da95decec9d4cbda95dece">[email 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, Office of the
Regional Counsel, Southwest Region, 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-2026-0730.
FOR FURTHER INFORMATION CONTACT: Steven Warwick, Aviation Safety
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
phone: (817) 222-5225; email: <a href="/cdn-cgi/l/email-protection#1063647566757e3e623e6771626779737b507671713e777f66"><span class="__cf_email__" data-cfemail="8cfff8e9fae9e2a2fea2fbedfefbe5efe7cceaededa2ebe3fa">[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 all Airbus Helicopters
Deutschland GmbH (AHD) Model MBB-BK 117 C-2 and MBB-BK 117 D-2
helicopters. The NPRM was published in the Federal Register on January
26, 2026 (91 FR 3092). The NPRM was prompted by EASA AD 2025-0188,
dated September 1, 2025, issued by EASA, which is the Technical Agent
for the Member States of the European Union (EASA AD 2025-0188) (also
referred to as the MCAI). The MCAI states that the standard MS18027
hook part number (P/N) 42305-283 installed on the large hook damper
assembly, P/N 44307-480, may be subject to localized yielding in the
mating threads when assembled to higher assembly torques.
In the NPRM, the FAA proposed to require modifying and re-
identifying the affected part or replacing the affected part with a
serviceable part. The FAA also proposed to prohibit installing an
affected part on any helicopter unless certain requirements are met.
The FAA is issuing this AD to prevent failure of the hook. The
unsafe condition, if not addressed, could result in failure of the
large hook damper assembly, which could result in loss of the hoist
load and injury to persons.
You may examine the MCAI in the AD docket at <a href="http://regulations.gov">regulations.gov</a> under
Docket No. FAA-2026-0730.
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 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. Except for minor editorial changes, this
AD is adopted as proposed in the NPRM. None of the changes will
increase the economic burden on any operator.
Material Incorporated by Reference Under 1 CFR Part 51
The FAA reviewed EASA AD 2025-0188, which specifies procedures for
modifying the large hook damper assembly having P/N 44307-480 by
replacing the standard MS18027 hook P/N 42305-283 with D-Lok hook P/N
42315-488 and reidentifying the large hook damper assembly to P/N
44307-480-1.
EASA AD 2025-0188 also specifies procedures for replacing large
hook damper assembly P/N 44307-480 with large hook damper assembly P/N
44307-480-1 (modification already accomplished) as an alternative to
the initial modification requirement. EASA AD 2025-0188 also prohibits
installing an affected large hook damper assembly having P/N 44307-480
on any helicopter unless certain requirements are met within 12 months
of the effective date of this AD and prohibits installing the affected
part on any helicopter.
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 183 helicopters of U.S.
registry.
The FAA estimates the following costs to comply with this AD:
Estimated Costs
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Cost per Cost on U.S.
Action Labor cost Parts cost product operators
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Modify hook and reidentify large hook 1 work-hour x $85 per $3,545 $3,630 $664,290
damper assembly. hour = $85.
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The FAA estimates the following cost to do any replacement that
would be an alternative method of compliance. The agency has no way of
determining the number of helicopters that might choose this
replacement:
Alternative Method Costs
----------------------------------------------------------------------------------------------------------------
Cost per
Action Labor cost Parts cost product
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Replace large hook damper assembly............ 1 work-hour x $85 per hour = $85 $23,867 $23,952
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[[Page 26908]]
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:
2026-09-08 Airbus Helicopters Deutschland GmbH (AHD): Amendment 39-
23329; Docket No. FAA-2026-0730; Project Identifier MCAI-2025-01416-
R.
(a) Effective Date
This airworthiness directive (AD) is effective June 17, 2026.
(b) Affected ADs
None.
(c) Applicability
This AD applies to all Airbus Helicopters Deutschland GmbH (AHD)
Model MBB-BK 117 C-2 and MBB-BK 117 D-2 helicopters, certificated in
any category.
(d) Subject
Joint Aircraft System Component (JASC) Code 2500, Cabin
Equipment/Furnishings.
(e) Unsafe Condition
This AD was prompted by the determination that the standard
MS18027 type hook may be subject to localized yielding in the mating
threads when assembled to higher assembly torques. The FAA is
issuing this AD to prevent failure of the hook. The unsafe
condition, if not addressed, could result in failure of the large
hook damper assembly, which could result in loss of the hoist load
and injury to persons.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Actions
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 AD 2025-0188,
dated September 1, 2025 (EASA AD 2025-0188).
(h) Exceptions to EASA AD 2025-0188
(1) Where EASA AD 2025-0188 refers to its effective date, this
AD requires using the effective date of this AD.
(2) Where the material referenced in EASA AD 2025-0188 specifies
``discard'', this AD requires replacing that text with ``remove from
service''.
(3) Where the material referenced in EASA AD 2025-0188 specifies
``check'', this AD requires replacing that text with ``inspect''.
(4) Where the material referenced in EASA AD 2025-0188 specifies
``if necessary clean the surface'', this AD requires replacing that
text with ``clean the surface''.
(5) This AD does not adopt the ``Remarks'' section of EASA AD
2025-0188.
(i) No Reporting Requirement
Although the material referenced in EASA AD 2025-0188 specifies
to submit information to the manufacturer, this AD does not require
those actions.
(j) Special Flight Permits
Special flight permits may be issued in accordance with 14 CFR
21.197 and 21.199 to operate the helicopter to a location where the
actions of this AD can be accomplished provided that no external
load is carried.
(k) 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 (l) of
this AD and email to: <a href="/cdn-cgi/l/email-protection#e8a9a5a7aba88e8989c68f879e"><span class="__cf_email__" data-cfemail="9ddcd0d2deddfbfcfcb3faf2eb">[email 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.
(l) Additional Information
For more information about this AD, contact Steven Warwick,
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410,
Westbury, NY 11590; phone: (817) 222-5225; email:
<a href="/cdn-cgi/l/email-protection#0477706172616a2a762a736576736d676f446265652a636b72"><span class="__cf_email__" data-cfemail="99eaedfceffcf7b7ebb7eef8ebeef0faf2d9fff8f8b7fef6ef">[email protected]</span></a>.
(m) 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 2025-0188,
dated September 1, 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#37767344775256445619524245584756195242"><span class="__cf_email__" data-cfemail="3b7a7f487b5e5a485a155e4e49544b5a155e4e">[email 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, Office of the
Regional Counsel, Southwest Region, 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/">www.archives.gov/federal-register/cfr/</a>ibr-locations or email <a href="/cdn-cgi/l/email-protection#85e3f7abecebf6f5e0e6f1eceaebc5ebe4f7e4abe2eaf3"><span class="__cf_email__" data-cfemail="a6c0d488cfc8d5d6c3c5d2cfc9c8e6c8c7d4c788c1c9d0">[email protected]</span></a>.
Issued on April 28, 2026.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft
Certification Service.
[FR Doc. 2026-09521 Filed 5-12-26; 8:45 am]
BILLING CODE 4910-13-P
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