EASA AD CF-2025-17
SUPERSEDED BY TCCA AD CF-2025-35
Summary
Canadian Airworthiness Directive CF-2025-17 is an emergency directive affecting Bell Textron Canada Limited model 505 helicopters, serial number 65011 and later, equipped with ballast kit Part Number SLS-706-201-007. The directive addresses a failure risk in the aft movable ballast box assembly door hinge that could lead to ballast weights striking the tail rotor, causing severe control issues. This directive mandates immediate removal and prohibition of ballast weights in the affected assembly.
What Changed
This new emergency Airworthiness Directive introduces a requirement to remove ballast weights from the aft movable ballast box assembly on affected Bell 505 helicopters before further flight. It prohibits the use of these ballast weights as of the effective date and references Bell Alert Service Bulletin 505-25-44 for compliance instructions. The directive serves as an interim safety measure pending further regulatory action.
Why It Matters
This directive is critical for aviation professionals because failure to comply could result in loss of tail rotor control and potential helicopter accidents. Operators, maintenance organizations, and compliance teams must address this unsafe condition promptly to ensure continued airworthiness and safety. The directive also highlights the importance of monitoring manufacturer service bulletins and regulatory updates for emergent safety issues.
What To Do
Affected operators must remove ballast weights from the aft movable ballast box assembly in accordance with Bell ASB 505-25-44 before the next flight. From the effective date of March 20, 2025, the use of ballast weights in the specified assembly is prohibited. Operators should coordinate with Transport Canada or authorized service centers for further guidance and monitor for any subsequent directives.