# [Amended]
**AGENCY:**
Federal Aviation Administration (FAA), DOT.
**ACTION:**
Notice of proposed rulemaking (NPRM).
**SUMMARY:**
The FAA proposes to adopt a new airworthiness directive (AD) for all General Atomics AeroTec Systems GmbH (General Atomics) Model Dornier 228-100, Dornier 228-101, Dornier 228-200, Dornier 228-201, Dornier 228-202, and Dornier 228-212 airplanes. This proposed AD was prompted by reports of specific part-numbered hydraulic pump motors becoming severely damaged by excessive heat. This proposed AD would require replacing the affected hydraulic pump motor with an improved design hydraulic pump motor. This proposed AD would also prohibit installing an affected hydraulic pump motor on any airplane. The FAA is proposing this AD to address the unsafe condition on these products.
**DATES:**
The FAA must receive comments on this NPRM by February 19, 2026.
**ADDRESSES:**
You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:
• *Federal eRulemaking Portal:* Go to *regulations.gov* . Follow the instructions for submitting comments.
• *Fax:* (202) 493-2251.
• *Mail:* U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
• *Hand Delivery:* Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
*AD Docket:* You may examine the AD docket at *regulations.gov* under Docket No. FAA-2025-5401; 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 NPRM, the mandatory continuing airworthiness information (MCAI), any comments received, and other information. The street address for Docket Operations is listed above.
**FOR FURTHER INFORMATION CONTACT:**
Doug Rudolph, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (816) 329-4059; email: *[email protected]* .
**SUPPLEMENTARY INFORMATION:**
**Comments Invited**
The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments using a method listed under *ADDRESSES* . Include “Docket No. FAA-2025-5401; Project Identifier MCAI-2025-01313-A” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments.
Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to *regulations.gov,* including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM.
**Confidential Business Information**
CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Doug Rudolph, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking.
**Background**
The European Union Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2025-0172, dated August 4, 2025 (EASA AD 2025-0172) (also referred to as the MCAI), to correct an unsafe condition on all General Atomics Model Dornier 228-100, Dornier 228-101, Dornier 228-200, Dornier 228-201, Dornier 228-202, and Dornier 228-212 airplanes. The MCAI states that several occurrences were reported where the hydraulic pump motor became severely damaged by excessive heat. The MCAI further states that it was determined that carbon brushes installed on the affected hydraulic pump motor were the root cause of the failures. This condition, if not corrected, could lead to an uncontained fire, possible injury to passengers and crew, and consequent loss of control of the airplane.
To address the unsafe condition, the brush manufacturer designed improved carbon brushes and General Atomics designed an improved hydraulic pump motor with these improved carbon brushes installed. The MCAI requires replacing the affected hydraulic pump motor with the improved hydraulic pump motor. The MCAI also prohibits installing the affected hydraulic pump motor on any airplane.
You may examine the MCAI in the AD docket at *regulations.gov* under Docket No. FAA-2025-5401.
**FAA's Determination**
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 and material referenced above. The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design.
**Proposed AD Requirements in This NPRM**
This proposed AD would require replacing the affected hydraulic pump motor with an improved design hydraulic pump motor. This proposed AD would also prohibit installing an affected hydraulic pump motor on any airplane.
**Costs of Compliance**
The FAA estimates that this AD, if adopted as proposed, would affect 16 airplanes of U.S. registry.
The FAA estimates the following costs to comply with this proposed AD:
| Action | Labor cost | Parts cost | Cost per | Cost on U.S. |
| --- | --- | --- | --- | --- |
| Replace hydraulic pump motor | 3 work-hours × $85 per hour = $255 | $8,900 | $9,155 | $146,480 |
**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**
The FAA determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 this proposed regulation:
(1) Is not a “significant regulatory action” under Executive Order 12866,
(2) Would not affect intrastate aviation in Alaska, and
(3) Would 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 Proposed Amendment**
Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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(g), 40113, 44701.
§ 39.13
2. The FAA amends § 39.13 by adding the following new airworthiness directive:
*General Atomics AeroTec Systems GmbH:* Docket No. FAA-2025-5401; Project Identifier MCAI-2025-01313-A.
**(a) Comments Due Date**
The FAA must receive comments on this airworthiness directive (AD) by February 19, 2026.
**(b) Affected ADs**
None.
**(c) Applicability**
This AD applies to General Atomics AeroTec Systems GmbH (Type Certificate previously held by RUAG Aerospace Services GmbH) Model Dornier 228-100, Dornier 228-101, Dornier 228-200, Dornier 228-201, Dornier 228-202, and Dornier 228-212 airplanes, all serial numbers, certificated in any category.
**(d) Subject**
Joint Aircraft System Component (JASC) Code 2913, Hydraulic Pump, (Elect/Eng), Main.
**(e) Unsafe Condition**
This AD was prompted by reports of several occurrences of hydraulic pump motors becoming severely damaged by excessive heat. The FAA is issuing this AD to prevent the overheating of the hydraulic pump motor. The unsafe condition, if not addressed, could result in an uncontained fire, possible injury to passengers and crew, and consequent loss of control of the airplane.
**(f) Compliance**
Comply with this AD within the compliance times specified, unless already done.
**(g) Required Actions**
For airplanes with an installed hydraulic pump motor having part number (P/N) 1259A, within 200 hours time-in-service of the hydraulic pump motor (for airplanes equipped with a hydraulic system elapsed time indicator), or 600 landings (for airplanes not equipped with a hydraulic system elapsed time indicator), as applicable, after the effective date of this AD, replace the hydraulic pump motor with a hydraulic pump motor having P/N A-752511A00B.
*Note to paragraph (g):* General Atomics AeroTec Service Bulletin Dornier 228 No. SB-228-360, Rev. 0, dated May 28, 2025, contains information related to this AD.
**(h) Installation Prohibition**
As of the effective date of this AD, do not install a hydraulic pump motor having P/N 1259A on any airplane.
**(i) 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 (j)(1) of this AD and email to: *[email protected].* 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.
**(j) Additional Information**
(1) 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: *[email protected].*
(2) For material identified in this AD that is not incorporated by reference, contact General Atomics AeroTec Systems GmbH, Galileostraße 396, D-82131 Gauting, Germany; phone: +49 8153 302280; email: *[email protected];* website: *ga-ats.com/.*
**(k) Material Incorporated by Reference**
None.
Issued on December 30, 2025.
Christopher R. Parker,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.