Rule2025-03442
Airworthiness Directives; Schempp-Hirth Flugzeugbau GmbH Gliders
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
March 4, 2025
Effective
April 8, 2025
Issuing agencies
Transportation DepartmentFederal Aviation Administration
Abstract
The FAA is adopting a new airworthiness directive (AD) for certain Schempp-Hirth Flugzeugbau GmbH Model Duo Discus and Duo Discus T gliders. This AD was prompted by reports of gliders' canopies opening during air tow. This AD requires modifying the canopy locking mechanism. The FAA is issuing this AD to address the unsafe condition on these products.
Full Text
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<title>Federal Register, Volume 90 Issue 41 (Tuesday, March 4, 2025)</title>
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[Federal Register Volume 90, Number 41 (Tuesday, March 4, 2025)]
[Rules and Regulations]
[Pages 11129-11131]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2025-03442]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2024-2135; Project Identifier MCAI-2024-00157-G;
Amendment 39-22972; AD 2025-04-14]
RIN 2120-AA64
Airworthiness Directives; Schempp-Hirth Flugzeugbau GmbH Gliders
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 Schempp-Hirth Flugzeugbau GmbH Model Duo Discus and Duo Discus
T gliders. This AD was prompted by reports of gliders' canopies opening
during air tow. This AD requires modifying the canopy locking
mechanism. The FAA is issuing this AD to address the unsafe condition
on these products.
DATES: This AD is effective April 8, 2025.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of April 8,
2025.
ADDRESSES:
AD Docket: You may examine the AD docket at <a href="http://regulations.gov">regulations.gov</a> under
Docket No. FAA-2024-2135; 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 Schempp-Hirth Flugzeugbau GmbH material identified in
this AD, contact Schempp-Hirth Flugzeugbau GmbH, Krebenstrasse 25,
Kirchheim unter Teck, Germany; phone: +49 7021 7298-0; email:
<a href="/cdn-cgi/l/email-protection#ea83848c85aa9989828f879a9ac7d68bca82988f8cd7" http: hirth.com">hirth.com</a>">info@schempp-<a href="http://hirth.com">hirth.com</a></a>; website: schempp-<a href="http://hirth.com">hirth.com</a>.
<bullet> You may view this material at the FAA, Airworthiness
Products Section, Operational Safety Branch, 901 Locust, Kansas City,
MO 64106. 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-2024-2135.
FOR FURTHER INFORMATION CONTACT: Fred Guerin, Aviation Safety Engineer,
FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (206)
231-2346; email: <a href="/cdn-cgi/l/email-protection#4d2b3f2829632a38283f24230d2b2c2c632a223b"><span class="__cf_email__" data-cfemail="14726671703a736171667d7a547275753a737b62">[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 Schempp-Hirth
Flugzeugbau GmbH Model Duo Discus and Duo Discus T gliders. The NPRM
published in the Federal Register on August 30, 2024 (89 FR 70580). The
NPRM was prompted by AD 2024-0059, dated March 5, 2024, issued by the
European Union Aviation Safety Agency (EASA), which is the Technical
Agent for the Member States of the European Union (EASA AD 2024-0059)
(also referred to as the MCAI). The MCAI states that occurrences have
been reported of the canopy opening during air tow on the Model Duo
Discus and Nimbus gliders. The investigation concluded that the
fuselage could be
[[Page 11130]]
temporarily deformed due to forces related to acceleration, which
allowed the locking mechanism to move into the open position. These
conditions, if not addressed, could lead to the canopy opening in
flight, resulting in loss of control of the glider.
In the NPRM, the FAA proposed to require modifying the canopy
locking mechanism. 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-2024-2135.
Discussion of Final Airworthiness Directive
Comments
The FAA received a comment from an individual who supported the
NPRM without change.
The FAA received additional comments from two individual
commenters. The following presents the comments received on the NPRM
and the FAA's response to each comment.
Requests To Withdraw the NPRM
An individual commenter noted that the service information was
presented by the factory on July 2, 2004, and it was not clear why in
October 2024 there is now an issue with these gliders. The commenter
further stated that the canopy locking mechanism works as designed when
used properly and that although an inexperienced pilot could close the
canopy, slide the levers forward, and not have the canopy properly
latched, learning how to correctly latch the canopy is a matter of
education rather than an indication that an AD is needed. The FAA
infers that the commenter requested that the NPRM be withdrawn.
Another commenter stated that an AD is not warranted because,
regardless of additional mechanisms, pilots must properly confirm
canopy closure and latching and brief passengers on remaining clear of
the canopy latch. The commenter mentioned that most instances of
canopies opening are the result of pilot error and personally witnessed
inexperienced pilots in the front seat rest their hand on the canopy
latch to catch airflow along the canopy and that this is an
unacceptable practice and should be corrected by the pilot in charge,
as well as covered during the pre-flight briefing with any new pilot or
passenger.
The FAA disagrees with the commenters' requests. The FAA issues an
AD once an unsafe condition has been identified and the unsafe
condition is likely to exist or develop in other products of the same
type design. Schempp-Hirth Flugzeugbau GmbH issued technical notes in
2004 and 2005 based upon data gathered from numerous glider operators.
However, a subsequent fatal accident in 2023 highlights the risk
associated with the inadequate design. While the FAA agrees with the
comment that a proper preflight inspection includes confirming a canopy
closure, the fatal accident in 2023 indicates that the risks associated
with the inadequate design still exist. The FAA agrees with EASA's risk
assessment that an unsafe condition exists on the affected gliders and
an AD action is necessary.
The FAA has not changed this AD regarding these comments.
Request To Revise Applicability
An individual commenter stated that the applicability in the
proposed AD is Schempp-Hirth Flugzeugbau GmbH Model Duo Discus and Duo
Discus T gliders, all serial numbers, certificated in any category, but
Schempp-Hirth Flugzeugbau Technical Note No. 380-1, No. 396-6, dated
July 27, 2004, with Appendix to Technical Note No. 380-1/396-6, only
specifies Duo Discus sailplanes with serial numbers 1 to 422. The FAA
infers that the commenter is requesting that the applicability be
revised to specify gliders with specific serial numbers.
The FAA agrees. The FAA revised paragraph (c) of this AD,
Applicability, to specify Schempp-Hirth Flugzeugbau GmbH Model Duo
Discus gliders serial numbers (S/Ns) 1 through 422 (inclusive) and Duo
Discus T gliders S/Ns 1 through 96 (inclusive), certificated in any
category.
Conclusion
These products have been approved by the 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, it has notified the FAA of the unsafe condition described in
the MCAI referenced above. The FAA reviewed the relevant data,
considered the 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
any other changes discussed 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 Schempp-Hirth Flugzeugbau GmbH Technical Note No.
380-1, No. 396-6 dated July 27, 2004, with Appendix to Technical Note
No. 380-1/396-6 attached (issued as one document); and Schempp-Hirth
Flugzeugbau GmbH Technical Note No. 868-4, No. 890-5 dated February 23,
2005, with Appendix to Technical Note No. 868-4/890-5 attached (issued
as one document), which specify procedures for installing a compression
spring in the canopy locking mechanism, installing spring washers at
the canopy actuating levers, and modifying the front actuating lever to
include a magnet and applying a red mark to the front and aft inside
the left canopy frame or installing a front actuating lever that has a
magnet.
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 and the MCAI
While the MCAI applies to Schempp-Hirth Flugzeugbau GmbH Model
Nimbus-4D and Nimbus-4DT/DM gliders, this AD does not because these
models do not have an FAA type certificate.
Costs of Compliance
The FAA estimates that this AD affects 34 gliders 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 canopy locking mechanism..... 2 work-hours x $85 per $100 $270 $9,180
hour = $170.
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[[Page 11131]]
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(f), 40113, 44701.
Sec. 39.13 [Amended]
0
2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive:
2025-04-14 Schempp-Hirth Flugzeugbau GmbH: Amendment 39-22972;
Docket No. FAA-2024-2135; Project Identifier MCAI-2024-00157-G.
(a) Effective Date
This airworthiness directive (AD) is effective April 8, 2025.
(b) Affected ADs
None.
(c) Applicability
This AD applies to Schempp-Hirth Flugzeugbau GmbH Model Duo
Discus gliders serial numbers (S/Ns) 1 through 422 (inclusive) and
Duo Discus T gliders S/Ns 1 through 96 (inclusive), certificated in
any category.
(d) Subject
Joint Aircraft System Component (JASC) Code 5200, Doors; 5210,
Passenger/Crew Doors.
(e) Unsafe Condition
This AD was prompted by reports of gliders' canopies opening
during air tow. The FAA is issuing this AD to address the canopy
locking mechanism opening during flight. The unsafe condition, if
not addressed, could lead to the canopy opening in flight, resulting
in loss of control of the glider.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Actions
Within 12 months after the effective date of this AD, modify the
canopy locking mechanism by installing a compression spring in the
canopy locking mechanism, installing spring washers at the canopy
actuating levers, modifying the front actuating lever to include a
magnet and applying a red mark to the front and aft inside the left
canopy frame; or installing a front actuating lever that has a
magnet, in accordance with the applicable technical note specified
in paragraph (g)(1) or (2) of this AD.
(1) For Model Duo Discus gliders: Appendix to Technical Note No.
380-1/396-6 attached to Schempp-Hirth Flugzeugbau GmbH Technical
Note No. 380-1, No. 396-6 dated July 27, 2004 (issued as one
document).
(2) For Model Duo Discus T gliders: Appendix to Technical Note
No. 868-4/890-5 attached to Schempp-Hirth Flugzeugbau GmbH Technical
Note No. 868-4, No. 890-5 dated February 23, 2005 (issued as one
document).
(h) 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 (i) of
this AD or email to: <a href="/cdn-cgi/l/email-protection#92d3dfddd1d2f4f3f3bcf5fde4"><span class="__cf_email__" data-cfemail="88c9c5c7cbc8eee9e9a6efe7fe">[email protected]</span></a>. If mailing information, also
submit information by email. 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.
(i) Additional Information
For more information about this AD, contact Fred Guerin,
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410,
Westbury, NY 11590; phone: (206) 231-2346; email:
<a href="/cdn-cgi/l/email-protection#b6d0c4d3d298d1c3d3c4dfd8f6d0d7d798d1d9c0"><span class="__cf_email__" data-cfemail="2a4c584f4e044d5f4f5843446a4c4b4b044d455c">[email protected]</span></a>.
(j) Material Incorporated by Reference
(1) The Director of the Federal Register approved the
incorporation by reference (IBR) 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) Schempp-Hirth Flugzeugbau GmbH Technical Note No. 380-1, No.
396-6 dated July 27, 2004, with Appendix to Technical Note No. 380-
1/396-6 attached (issued as one document).
(ii) Schempp-Hirth Flugzeugbau GmbH Technical Note No. 868-4,
No. 890-5 dated February 23, 2005, with Appendix to Technical Note
No. 868-4/890-5 attached (issued as one document).
(3) For Schempp-Hirth Flugzeugbau GmbH material identified in
this AD, contact Schempp-Hirth Flugzeugbau GmbH, Krebenstrasse 25,
Kirchheim unter Teck, Germany; phone: +49 7021 7298-0; email:
<a href="/cdn-cgi/l/email-protection#10797e767f50637378757d60603d2c7130786275762d" http: hirth.com">hirth.com</a>">info@schempp-<a href="http://hirth.com">hirth.com</a></a>; website: schempp-<a href="http://hirth.com">hirth.com</a>.
(4) You may view this material at the FAA, Airworthiness
Products Section, Operational Safety Branch, 901 Locust, Kansas
City, MO 64106. 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#3b5d49155255484b5e584f5254557b555a495a155c544d"><span class="__cf_email__" data-cfemail="5137237f383f2221343225383e3f113f3023307f363e27">[email protected]</span></a>.
Issued on February 21, 2025.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft
Certification Service.
[FR Doc. 2025-03442 Filed 3-3-25; 8:45 am]
BILLING CODE 4910-13-P
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