EASA AD CF-2024-18
Rotors Flight Control — Cyclic Stick Tube Cracking
Summary
Canadian Airworthiness Directive CF-2024-18 addresses cracking in the cyclic stick tube assembly on Bell Textron Canada Limited model 407 helicopters with specific serial numbers and part numbers 206-001-342-101 or 206-001-342-101FM. The directive mandates revisions to the Interior and Prestart Check procedures and requires inspections and corrective actions to detect and repair or replace cracked cyclic stick tubes. This AD aims to prevent in-flight failure of the cyclic stick tube and potential loss of helicopter control.
What Changed
CF-2024-18 introduces mandatory revisions to the Rotorcraft Flight Manuals for affected Bell 407 helicopters to limit cyclic stick movement during prestart checks. It also requires a one-time detailed inspection of the cyclic stick tube assembly and mandates repair or replacement if cracks are found. The directive enforces compliance with Bell Alert Service Bulletin 407-23-130 and establishes repetitive inspection intervals for repaired parts.
Why It Matters
This directive is critical for aviation professionals to ensure flight safety by preventing cyclic stick tube failure due to fatigue cracking. Operators and maintenance teams must update procedures and perform inspections to detect early signs of cracking, reducing the risk of in-flight control loss. Compliance ensures continued airworthiness and regulatory adherence for affected Bell 407 helicopters.
What To Do
Operators of affected Bell 407 helicopters must revise their Rotorcraft Flight Manuals within 100 flight hours or 90 days from 2024-06-12, whichever occurs first, and inform flight crews of the changes. They must also conduct detailed inspections of the cyclic stick tube assembly within the same timeframe and repair or replace any cracked parts following Bell ASB 407-23-130. Repaired parts require ongoing inspections every 300 hours or 6 months and must be replaced within 24 months.