Federal Aviation Administration (FAA), DOT.
Notice of proposed rulemaking (NPRM).
The FAA proposes to adopt a new airworthiness directive (AD) for all MHI RJ Aviation ULC Model CL-600-2C10 (Regional Jet Series 700, 701 & 702), CL-600-2C11 (Regional Jet Series 550), Model CL-600-2D15 (Regional Jet Series 705), CL-600-2D24 (Regional Jet Series 900), and CL-600-2E25 (Regional Jet Series 1000). This proposed AD was prompted by an engine indicating and crew alerting system (EICAS) STAB TRIM Caution message that was posted, and subsequent repair that found prematurely worn teeth on a rubber bull gear (RBG) wheel in the horizontal stabilizer trim actuator (HSTA). This proposed AD would require an inspection for part numbers and on-condition replacement of affected RBG wheels and prohibit the installation of affected parts under certain conditions, as specified in a Transport Canada AD, which is proposed for incorporation by reference (IBR). The FAA is proposing this AD to address the unsafe condition on these products.
The FAA must receive comments on this proposed AD by May 30, 2025.
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. ( print page 15665)
- 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-2025-0619; 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.
Material Incorporated by Reference:
- For Transport Canada material identified in this proposed AD, contact Transport Canada, Transport Canada National Aircraft Certification, 159 Cleopatra Drive, Nepean, Ontario K1A 0N5, Canada; telephone 888-663-3639; email[email protected]. You may find this material on the Transport Canada website at tc.canada.ca/en/aviation. It is also available at regulations.gov under Docket No. FAA-2025-0619.
- You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195.