Airworthiness Directives; Diamond Aircraft Industries Inc. Airplanes

Issuing agencies

Abstract

The FAA is adopting a new airworthiness directive (AD) for all Diamond Aircraft Industries Inc. (DAI) Model DA 40, DA 40 F, and DA 40 NG airplanes. This AD was prompted by several reports of passenger door separation during flight. This AD requires revising the existing airplane flight manual (AFM) to provide the flight crew with revised operating limitations, emergency procedures, and normal operating procedures; inspecting the passenger door latching mechanism and safety hook mechanism areas and performing corrective action, as applicable; inspecting the safety hook, latching bolts, front and rear door guide blocks, canopy and passenger door warning light, carbon hinges, tension spring, retaining block, safety hook push button, latching mechanism spring, gas spring, and door frame; measuring the passenger door handle actuation force; modifying the airplane with placards; replacing the gas spring; and replacing the hook assembly, retaining block, door guide blocks, and door sealant if necessary. 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 210 (Monday, November 2, 2026)</title>
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<body><pre>
[Federal Register Volume 91, Number 210 (Monday, November 2, 2026)]
[Rules and Regulations]
[Pages 68873-68876]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-22310]



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Rules and Regulations
                                                Federal Register
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Federal Register / Vol. 91, No. 210 / Monday, November 2, 2026 / 
Rules and Regulations

[[Page 68873]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2026-4633; Project Identifier MCAI-2025-01173-A; 
Amendment 39-23508; AD 2026-22-06]
RIN 2120-AA64


Airworthiness Directives; Diamond Aircraft Industries Inc. 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all 
Diamond Aircraft Industries Inc. (DAI) Model DA 40, DA 40 F, and DA 40 
NG airplanes. This AD was prompted by several reports of passenger door 
separation during flight. This AD requires revising the existing 
airplane flight manual (AFM) to provide the flight crew with revised 
operating limitations, emergency procedures, and normal operating 
procedures; inspecting the passenger door latching mechanism and safety 
hook mechanism areas and performing corrective action, as applicable; 
inspecting the safety hook, latching bolts, front and rear door guide 
blocks, canopy and passenger door warning light, carbon hinges, tension 
spring, retaining block, safety hook push button, latching mechanism 
spring, gas spring, and door frame; measuring the passenger door handle 
actuation force; modifying the airplane with placards; replacing the 
gas spring; and replacing the hook assembly, retaining block, door 
guide blocks, and door sealant if necessary. The FAA is issuing this AD 
to address the unsafe condition on these products.

DATES: This AD is effective December 7, 2026.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of December 7, 
2026.

ADDRESSES: 
    AD Docket: You may examine the AD docket at <a href="http://regulations.gov">regulations.gov</a> under 
Docket No. FAA-2026-4633; 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 Diamond Aircraft material identified in this AD, 
contact DAI, 1560 Crumlin Sideroad, London, Ontario, Canada, N5V 1S2; 
phone: (519) 457-4041; email: <a href="/cdn-cgi/l/email-protection#aad9dfdadac5d8de87c9cbc4cbcecbea96cb8ac2d8cfcc97" http: diamondaircraft.com">diamondaircraft.com</a>">support-canada@<a href="http://diamondaircraft.com">diamondaircraft.com</a></a>; 
website: <a href="http://diamondaircraft.com">diamondaircraft.com</a>.
    <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-2026-4633.

FOR FURTHER INFORMATION CONTACT: Fatin Saumik, Aviation Safety 
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; 
phone: (516) 228-7300; email: <a href="/cdn-cgi/l/email-protection#224443564b4c0c500c5143574f4b49624443430c454d54"><span class="__cf_email__" data-cfemail="7b1d1a0f1215550955081a0e1612103b1d1a1a551c140d">[email&#160;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 DAI Model DA 40, DA 
40 F, and DA 40 NG airplanes. The NPRM was published in the Federal 
Register on May 13, 2026 (91 FR 26952). The NPRM was prompted by 
Transport Canada AD CF-2025-30, dated June 23, 2025 (referred to as the 
MCAI), issued by Transport Canada, which is the aviation authority for 
Canada. The MCAI states that there have been several reports of 
passenger door separation. DAI attributed the root cause of certain 
instances to the passenger door not being properly latched and 
subsequent attempts to latch the passenger door in flight. DAI was 
unable to find a definitive root cause of the remaining occurrences. 
Passenger door separation, if not addressed, could result in damage to 
the airplane structure and lead to loss of control of the airplane and 
injury to persons on the ground.
    In the NPRM, the FAA proposed to require revising the existing AFM 
to provide the flight crew with revised operating limitations, 
emergency procedures, and normal operating procedures; inspecting the 
passenger door latching mechanism and safety hook mechanism areas and 
performing corrective action, as applicable; inspecting the safety 
hook, latching bolts, front and rear door guide blocks, canopy and 
passenger door warning light, carbon hinges, tension spring, retaining 
block, safety hook push button, latching mechanism spring, gas spring, 
and door frame; measuring the passenger door handle actuation force; 
modifying the airplane with placards; replacing the gas spring; and 
replacing the hook assembly, retaining block, door guide blocks, and 
door sealant if necessary. 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-2026-4633.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from four individual commenters. Three 
commenters requested that the FAA revise the applicability of the 
proposed AD, and one commenter requested a change concerning the 
service information specified in the proposed AD. The following 
presents the comments received on the NPRM and the FAA's response to 
each comment.

Request To Limit Applicability

    Three individual commenters requested that the FAA revise the 
applicability of the proposed AD to exclude newer serial-numbered 
airplanes. The commenters stated that the unsafe condition resulted 
from early generation door locking architectures and that newer 
airplanes are equipped with a secondary safety latch that completely 
eliminates the unsafe condition. The commenters stated that applying 
the AD to all Model DA 40, DA 40 F, and DA 40 NG airplanes would impose 
unnecessary maintenance requirements on airplanes already equipped with 
this safety mechanism.

[[Page 68874]]

    The FAA disagrees with the request. According to DAI, there are two 
configurations of the door handle, an older and a newer configuration, 
and both configurations include a red safety hook. However, the red 
safety hook was not designed to hold the door closed during takeoff 
and, therefore, does not completely eliminate the unsafe condition. The 
FAA, in working with Transport Canada and DAI, has determined that the 
secondary safety latch does not resolve the unsafe condition and that 
the unsafe condition is not limited to older serial-numbered airplanes. 
The Model DA 40 NG is the latest model, and it has experienced several 
occurrences of door separation. Therefore, the FAA did not change this 
AD as a result of these comments.

Request To Allow Later Revisions of Service Information

    An individual commenter requested that the FAA revise the proposed 
AD to allow the use of later revisions of the service information, 
rather than specifying the individual revisions of the service 
information for which credit would be provided. The commenter stated 
that allowing later revisions would permit the manufacturer to 
incorporate improvements into the service information without requiring 
owners to repeat an inspection unnecessarily.
    The FAA disagrees with the request to allow credit for later 
revision of the service material because referring to documents that do 
not exist at the time the AD is published violates Office of the 
Federal Register (OFR) regulations regarding approval of materials 
``incorporated by reference'' in rules. These OFR regulations require 
that either the service document be submitted for approval by the OFR 
as ``referenced'' material, in which case it may be simply called out 
in the text of an AD, or the service document contents be published as 
part of the actual AD language. An AD may reference only the specific 
service document that was submitted and approved by the OFR for 
``incorporation by reference.'' In order for operators to use later 
revisions of the referenced document (issued after the publication of 
the AD), either the FAA must revise the AD to reference the specific 
later revisions, or operators must request the approval of their use as 
an alternative method of compliance (under the provisions of paragraph 
(l) of this AD). Therefore, the FAA did not change this AD as a result 
of this comment.

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. Except for 
minor editorial changes, and any other changes described previously, 
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 Diamond Aircraft Mandatory Service Bulletin MSB 
40-103/MSB F4-042/MSB D4-114/MSB 40NG-084 REV. 2, dated June 5, 2025 
(issued as one document), published with Diamond Aircraft Work 
Instruction WI-MSB 40-103/WI-MSB F4-042/WI-MSB D4-114/WI-MSB 40NG-084 
REV. 2, dated June 5, 2025 (issued as one document). This material 
specifies procedures for inspecting the passenger door latching 
mechanism and safety hook mechanism areas and performing corrective 
action, as applicable; inspecting the safety hook, latching bolts, 
front and rear door guide blocks, canopy and passenger door warning 
light, carbon hinges, tension spring, retaining block, safety hook push 
button, latching mechanism spring, gas spring, and door frame; 
measuring the passenger door handle actuation force; modifying the 
airplane with placards; replacing the gas spring; and replacing the 
hook assembly, retaining block, door guide blocks, and door sealant if 
necessary for Model DA 40, DA 40 F, and DA 40 NG airplanes.
    The FAA also reviewed Diamond Aircraft DA 40 AFM Doc. No. 6.01.01-E 
Temporary Revision TR-MAM-40-1203, Door Latching and Locking, dated 
December 16, 2024; Diamond Aircraft DA 40 F AFM Doc. No. 6.01.02-E 
Temporary Revision TR-MAM-40-1203, Door Latching and Locking, dated 
December 16, 2024; and Diamond Aircraft DA 40 NG AFM Doc. No. 6.01.15-E 
Temporary Revision TR-MAM-40-1203/a, Door Latching and Locking, dated 
February 18, 2025. This material specifies procedures for amending the 
AFM by revising the operating limitations, emergency procedures, and 
normal operating procedures related to door latching and locking for 
Model DA 40, DA 40 F, and DA 40 NG airplanes.
    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.

Differences Between This AD, the MCAI, and the Referenced Material

    The MCAI applies to DAI Model DA 40 D airplanes, but this AD does 
not include this model because it does not have an FAA type 
certificate.
    The service bulletin referred to in the MCAI specifies to contact 
DAI for repair instructions, but this AD requires contacting the 
Manager, International Validation Branch, FAA; Transport Canada; or 
DAI's Transport Canada Design Organization Approval (DOA) instead.
    The material referenced above specifies recording any findings in 
the execution report and submitting the execution report to DAI, but 
this AD does not include that requirement.

Interim Action

    The FAA considers this AD an interim action. This unsafe condition 
is still under investigation by the manufacturer and, depending on the 
results of that investigation, the FAA may consider further rulemaking 
action.

Costs of Compliance

    The FAA estimates that this AD affects 987 airplanes of U.S. 
registry.
    The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
              Action                    Labor cost        Parts cost      Cost per product        operators
----------------------------------------------------------------------------------------------------------------
AFM revision.....................  1 work-hour x $85                $0  $85................  $83,895.
                                    per hour = $85.
Initial inspection...............  3 work-hours x $85               76  $331...............  $326,697.
                                    per hour = $255.

[[Page 68875]]

 
Repetitive inspections...........  1 work-hour x $85                 0  $85 per inspection.  $83,895 per
                                    per hour = $85 per                                        inspection.
                                    inspection.
----------------------------------------------------------------------------------------------------------------

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

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Gas spring replacement........................  2 work-hours x $85 per hour =               $489            $659
                                                 $170.
Hook assembly replacement.....................  4 work-hours x $85 per hour =                484             824
                                                 $340.
Retaining block replacement...................  1 work-hour x $85 per hour = $85             166             251
Door guide block replacement..................  1 work-hour x $85 per hour = $85             206             291
Door sealant replacement......................  1 work-hour x $85 per hour = $85              15             100
----------------------------------------------------------------------------------------------------------------

    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:

2026-22-06 Diamond Aircraft Industries Inc.: Amendment 39-23508; 
Docket No. FAA-2026-4633; Project Identifier MCAI-2025-01173-A.

(a) Effective Date

    This airworthiness directive (AD) is effective December 7, 2026.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all Diamond Aircraft Industries Inc. (DAI) 
Model DA 40, DA 40 F, and DA 40 NG airplanes, certificated in any 
category.

(d) Subject

    Joint Aircraft System Component (JASC) Code 5210, Passenger/Crew 
Doors.

(e) Unsafe Condition

    This AD was prompted by several reports of passenger door 
separation during flight. The FAA is issuing this AD to address this 
unsafe condition. The unsafe condition, if not addressed, could 
result in damage to the airplane structure and lead to loss of 
control of the airplane and injury to persons on the ground.

(f) Definition

    For the purpose of this AD, the Diamond Aircraft work 
instruction is defined as Diamond Aircraft Work Instruction WI-MSB 
40-103/WI-MSB F4-042/WI-MSB D4-114/WI-MSB 40NG-084 REV. 2, dated 
June 5, 2025 (issued as one document), published with Diamond 
Aircraft Mandatory Service Bulletin MSB 40-103/MSB F4-042/MSB D4-
114/MSB 40NG-084 REV. 2, dated June 5, 2025 (issued as one 
document).

(g) Applicable Airplane Flight Manual (AFM) Temporary Revisions

    The following presents the AFM and temporary revisions that 
apply to this AD and each individual model.
    (1) For Model DA 40 airplanes: Diamond Aircraft DA 40 AFM Doc. 
No. 6.01.01-E Temporary Revision TR-MAM-40-1203, Door Latching and 
Locking, dated December 16, 2024.
    (2) For Model DA 40 F airplanes: Diamond Aircraft DA 40 F AFM 
Doc. No. 6.01.02-E Temporary Revision TR-MAM-40-1203, Door Latching 
and Locking, dated December 16, 2024.
    (3) For Model DA 40 NG airplanes: Diamond Aircraft DA 40 NG AFM 
Doc. No. 6.01.15-E Temporary Revision TR-MAM-40-1203/a, Door 
Latching and Locking, dated February 18, 2025.

(h) Compliance

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

[[Page 68876]]

(i) Required Actions

    (1) Within 100 hours time-in-service (TIS) or 100 days, 
whichever occurs first after the effective date of this AD, revise 
the existing AFM for the airplane to include the information 
specified in the applicable AFM temporary revision specified in 
paragraphs (g)(1) through (3) of this AD.
    (i) The owner/operator (pilot) holding at least a private pilot 
certificate may revise the existing AFM for the airplane and must 
enter compliance with the applicable paragraph of this AD into the 
airplane maintenance 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.
    (ii) The AFM revision required by paragraph (i)(1) of this AD 
may be accomplished before the initial inspection and modification 
required by paragraph (i)(2) or (3) of this AD for that airplane.
    (2) For airplanes with less than 100 total hours TIS as of the 
effective date of this AD: Within 100 hours TIS or 100 days, 
whichever occurs first after the effective date of this AD, 
accomplish the initial inspection of the safety hook, latching 
bolts, front and rear door guide blocks and the modification of the 
airplane with placards in accordance with the instructions of 
Section III, steps 5, 20 through 23, 28, 30, 31, and 33 through 36 
in the Diamond Aircraft Work Instruction specified in paragraph (f) 
of this AD, except accomplish the actions required by step 20(f) in 
accordance with paragraphs (i)(4) and (5) of this AD.
    (3) For airplanes that have accumulated 100 or more total hours 
TIS as of the effective date of this AD: Within 100 hours TIS or 100 
days, whichever occurs first after the effective date of this AD, 
accomplish the initial inspection of the canopy and passenger door 
warning light, carbon hinges, safety hook, tension spring, retaining 
block, safety hook push button, safety hook mechanism, latching 
mechanism spring, gas spring, latching bolts, front and rear door 
guide blocks, and door frame; measure the passenger door handle 
actuation force; and accomplish the modification of the airplane 
with placards in accordance with the instructions of Section III, 
steps 2 through 10, 12, 13, 15, 17, 18, 20 through 24, and 28 
through 36 in the Diamond Aircraft Work Instruction specified in 
paragraph (f) of this AD, except accomplish the actions required by 
step 20(f) in accordance with paragraphs (i)(4) and (5) of this AD.
    (4) If, during the inspection required by step 20(f) in the 
Diamond Aircraft Work Instruction specified in paragraph (f) of this 
AD, the force measured is less than 1.8 kg (18 N), and if the force 
measured during the inspection required by step 20(c) was between 2 
kg (20 N) and 6 kg (60 N), perform the following:
    (i) Repeat the inspection required by step 20(c) in the Diamond 
Aircraft Work Instruction specified in paragraph (f) of this AD 
every 100 hours TIS until the replacement of the gas spring required 
by paragraph (i)(4)(ii) of this AD is accomplished.
    (ii) Within 12 months after the effective date of this AD, 
replace the gas spring in accordance with the Diamond Aircraft Work 
Instruction specified in paragraph (f) of this AD.
    (5) If, during the inspection specified in step 20(f) in the 
Diamond Aircraft Work Instruction specified in paragraph (f) of this 
AD, the force measured is less than 1.8 kg (18 N), and if the force 
measured during the inspection required by step 20(c) was greater 
than 6 kg (60 N) or less than 2 kg (20 N), before further flight, 
replace the gas spring.
    (6) If, during any inspection as required by paragraph (i)(2) or 
(3) of this AD, any findings, as defined in Section III, steps 5, 6, 
9, 12, 20, and 23 are identified, before further flight, accomplish 
the applicable corrective action(s) in accordance with the 
instructions of Section IV, IV.1, steps 1 through 9, VI.2 [sic], 
steps 1 and 2, VI.3 [sic], steps 1 and 2, and VI.4 [sic], steps 1 
through 5 in the Diamond Aircraft Work Instruction specified in 
paragraph (f) of this AD.
    (7) Where the instructions of Section III or Section IV of the 
Diamond Aircraft Work Instruction specified in paragraph (f) of this 
AD state to contact the manufacturer ``in case of doubt'' or for 
approved instructions, this AD requires before further flight, using 
instructions approved by the Manager, International Validation 
Branch, FAA; Transport Canada; or DAI's Transport Canada Design 
Organization Approval (DOA), and within the compliance time 
specified therein, accomplishing those instructions. If approved by 
the DOA, the approval must include the DOA-authorized signature.

(j) No Reporting Requirement

    Although the material referenced in paragraph (f) of this AD 
specifies to submit information to the manufacturer, this AD does 
not require that action.

(k) Credit for Previous Actions

    You may take credit for the actions required by paragraph (i) of 
this AD if you performed those actions before the effective date of 
this AD using Diamond Aircraft Mandatory Service Bulletin MSB 40-
103/MSB F4-042/MSB D4-114/MSB 40NG-084 REV. 1, dated May 15, 2025 
(issued as one document), published with Diamond Aircraft Work 
Instruction WI-MSB 40-103/WI-MSB F4-042/WI-MSB D4-114/WI-MSB 40NG-
084 REV. 1, dated May 15, 2025 (issued as one document); or Diamond 
Aircraft Mandatory Service Bulletin MSB 40-103/MSB F4-042/MSB D4-
114/MSB 40NG-084 REV. 0, dated March 20, 2025 (issued as one 
document), published with Diamond Aircraft Work Instruction WI-MSB 
40-103/WI-MSB F4-042/WI-MSB D4-114/WI-MSB 40NG-084 REV. 0, dated 
March 20, 2025 (issued as one document).

(l) Alternative Methods of Compliance (AMOCs)

    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 (m) of 
this AD and email to: <a href="/cdn-cgi/l/email-protection#91d0dcded2d1f7f0f0bff6fee7"><span class="__cf_email__" data-cfemail="82c3cfcdc1c2e4e3e3ace5edf4">[email&#160;protected]</span></a>. 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.

(m) Additional Information

    For more information about this AD, contact Fatin Saumik, 
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: (516) 228-7300; email: 
<a href="/cdn-cgi/l/email-protection#b9dfd8cdd0d797cb97cad8ccd4d0d2f9dfd8d897ded6cf"><span class="__cf_email__" data-cfemail="731512071a1d5d015d0012061e1a18331512125d141c05">[email&#160;protected]</span></a>.

(n) 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) Diamond Aircraft Mandatory Service Bulletin MSB 40-103/MSB 
F4-042/MSB D4-114/MSB 40NG-084 REV. 2, dated June 5, 2025 (issued as 
one document), published with Diamond Aircraft Work Instruction WI-
MSB 40-103/WI-MSB F4-042/WI-MSB D4-114/WI-MSB 40NG-084 REV. 2, dated 
June 5, 2025 (issued as one document).
    (ii) Diamond Aircraft DA 40 Airplane Flight Manual (AFM) Doc. 
No. 6.01.01-E Temporary Revision TR-MAM-40-1203, Door Latching and 
Locking, dated December 16, 2024.
    (iii) Diamond Aircraft DA 40 F AFM Doc. No. 6.01.02-E Temporary 
Revision TR-MAM-40-1203, Door Latching and Locking, dated December 
16, 2024.
    (iv) Diamond Aircraft DA 40 NG AFM Doc. No. 6.01.15-E Temporary 
Revision TR-MAM-40-1203/a, Door Latching and Locking, dated February 
18, 2025.
    (3) For Diamond Aircraft material identified in this AD, contact 
Diamond Aircraft Industries Inc., 1560 Crumlin Sideroad, London, 
Ontario, Canada, N5V 1S2; phone: (519) 457-4041; email: <a href="/cdn-cgi/l/email-protection#c7b4b2b7b7a8b5b3eaa4a6a9a6a3a687fba6e7afb5a2a1fa" http: diamondaircraft.com">diamondaircraft.com</a>">support-canada@<a href="http://diamondaircraft.com">diamondaircraft.com</a></a>; website: <a href="http://diamondaircraft.com">diamondaircraft.com</a>.
    (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#b8deca96d1d6cbc8dddbccd1d7d6f8d6d9cad996dfd7ce"><span class="__cf_email__" data-cfemail="6107134f080f1211040215080e0f210f0013004f060e17">[email&#160;protected]</span></a>.

    Issued on October 26, 2026.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2026-22310 Filed 10-30-26; 8:45 am]
BILLING CODE 4910-13-P


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