Airworthiness Directives; General Atomics AeroTec Systems GmbH (Type Certificate Previously Held by RUAG Aerospace Services GmbH) Airplanes

DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA-2025-5401; Project Identifier MCAI-2025-01313-A] RIN 2120-AA64 Airworthiness Directives; General Atomics AeroTec Systems GmbH (Type Certificate Previously Held by RUAG Aerospace Services GmbH) Airplanes 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

ences 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

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:

Estimated Costs Action Labor cost Parts cost Cost per product Cost on U.S. operators 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

S. operators 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

y

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.

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: AMOC@faa.gov. 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 doug.rudolph@faa.gov.

(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: custsupport.dornier228@ga-ats.com; 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.

[FR Doc. 2025-24233 Filed 1-2-26; 8:45 am] BILLING CODE 4910-13-P