90 FR 41 pgs. 11129-11131 - Airworthiness Directives; Schempp-Hirth Flugzeugbau GmbH Gliders
Type: RULEVolume: 90Number: 41Pages: 11129 - 11131
Pages: 11129, 11130, 11131Docket number: [Docket No. FAA-2024-2135; Project Identifier MCAI-2024-00157-G; Amendment 39-22972; AD 2025-04-14]
FR document: [FR Doc. 2025-03442 Filed 3-3-25; 8:45 am]
Agency: Transportation Department
Sub Agency: Federal Aviation Administration
Official PDF Version: PDF Version
[top]
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.
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 regulations.gov 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:
• 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: info@schempp-hirth.com; website: schempp-hirth.com.
• 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 regulations.gov 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: fred.guerin@faa.gov .
SUPPLEMENTARY INFORMATION:
Background
[top] 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
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 regulations.gov 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:
| Action | Labor cost | Parts cost | Cost per product | Cost on U.S. operators |
|---|---|---|---|---|
| Modify canopy locking mechanism | 2 work-hours × $85 per hour = $170 | $100 | $270 | $9,180 |
[top]
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
1. The authority citation for part 39 continues to read as follows:
Authority:
49 U.S.C. 106(f), 40113, 44701.
§?39.13 [Amended]
2. The FAA amends §?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: AMOC@faa.gov. 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: fred.guerin@faa.gov.
(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: info@schempp-hirth.com; website: schempp-hirth.com.
(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 www.archives.gov/federal-register/cfr/ibr-locations or email fr.inspection@nara.gov .
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