EASA AD CF-2024-12R1
Landing Gear — Uncommanded Steering Due to Nosewheel Steering Potentiometer Universal Coupling Setscrew Failure
Summary
The Canadian Airworthiness Directive CF-2024-12R1 addresses uncommanded steering issues caused by failure of the nosewheel steering potentiometer universal coupling setscrews on Bombardier CL-600-1A11, CL-600-2A12, and CL-600-2B16 aircraft models. This directive mandates replacement of the coupling setscrews and updates maintenance procedures to prevent runway excursions due to steering malfunctions. It applies to all serial numbers of the affected Bombardier Challenger aircraft.
What Changed
CF-2024-12R1 revises the previous AD CF-2024-12 by correcting an omission in Table 2 regarding the Time Limits/Maintenance Checks (TLMC) manual for the CL-600-2B16 (Challenger 650) model. The directive maintains all prior requirements but updates the TLMC task references to include the Challenger 650. No other changes to the corrective actions or compliance requirements were made.
Why It Matters
This directive is critical for aviation professionals to ensure safe ground handling and prevent runway excursions caused by unintended nosewheel steering inputs. Operators and maintenance teams must comply to maintain aircraft airworthiness and avoid operational disruptions. The updated TLMC tasks help standardize maintenance practices across all affected Bombardier Challenger variants, improving reliability and safety.
What To Do
Operators must replace the nosewheel steering potentiometer universal coupling setscrews within 36 months or 1400 flight hours from August 27, 2024, whichever occurs first. Additionally, the new TLMC task must be incorporated within 60 days of the effective date, with recurring maintenance actions scheduled every 96 months thereafter. Compliance with updated Bombardier Service Bulletins and TLMC manuals is required to meet the directive's mandates.