Final rule · 2026-04465

Airworthiness Directives; MHI RJ Aviation ULC (Type Certificate Previously Held by Bombardier, Inc.) Airplanes

The FAA is superseding Airworthiness Directive (AD) 2023-23- 02, which applied to all MHI RJ Aviation ULC Model CL-600-2B19 (Regional Jet Series 100 & 440), CL-600-2C10 (Regional Jet Series 700, 701 & 702), CL-600-2C11 (Regional Jet Series 550), CL-600-2D15 (Regional Jet Series 705), CL-600-2D24 (Regional Jet Series 900), and CL-600-2E25 (Regional Jet Series 1000) airplanes. AD 2023-23-02 required, for certain airplanes, revising the existing maintenance or inspection program, as applicable, to incorporate new or more restrictive airworthiness limitations; and accomplishing certain aircraft maintenance manual (AMM) tasks and corrective actions following short-term or long-term storage. Since the FAA issued AD 2023-23-02, additional power control unit (PCU) disconnect findings show that the task intervals must be reduced to allow earlier detection of potential single PCU disconnect cases. This AD continues to require certain actions in AD 2023-23-02 and requires repetitive operational checks of the rudder PCUs and repetitive operational tests of the elevator PCUs. The FAA is issuing this AD to address the unsafe condition on these products.