Airworthiness Directives; Bell Textron Canada Limited Helicopters
Key claim: The FAA is superseding AD 2024-02-55 to require replacement of the vertical stabilizer top end cap assembly on certain Bell Model 505 helicopters with an improved design, which terminates the recurring inspections.
Abstract
(Rule · Transportation Department, Federal Aviation Administration) The FAA is superseding Airworthiness Directive (AD) 2024-02- 55, which applies to certain Bell Textron Canada Limited (BTCL) Model 505 helicopters. AD 2024-02-55 required initial and recurring inspections of the vertical stabilizer top end cap assembly and corrective action if a crack is found. Since the FAA issued AD 2024-02- 55, the manufacturer introduced a new one- piece vertical stabilizer machined top end cap assembly, which is implemented during production, and designed a new replacement for the vertical stabilizer machined top end cap assembly currently in service. This AD continues to require the inspection requirements of AD 2024-02- 55 and would limit the applicability to exclude certain serial numbered BTCL Model 505 helicopters with an improved design vertical stabilizer top end cap installed at production. This AD also requires replacing the vertical stabilizer top end cap assembly with an improved design top end cap assembly, which constitutes a terminating action for the recurring detailed visual inspections. The FAA is issuing this AD to address the unsafe condition on these products.
Why this matters
This supersedure converts a recurring inspection regime for vertical stabilizer top end cap cracking on Bell 505 helicopters into a one-time terminating replacement with an improved design, reducing ongoing maintenance burden while addressing the underlying unsafe condition. It illustrates the FAA’s typical AD lifecycle where interim inspection-based mitigations are eventually retired once a redesigned part is certified.