AD FAA-2025-1735

The FAA is superseding Airworthiness Directive (AD) 2021-20- 16, which applied to all Airbus Helicopters Model AS355E, AS 355-F, AS 355-F1, AS355F2, AS355N, and AS355NP helicopters and certain Model AS 350B3 helicopters. AD 2021-20-16 required repetitive cleaning and visual and detailed inspections of the right-hand side of the vertical fin spar and vertical fin upper attachments for discrepancies (cracking) with corrective action, if necessary. Since the FAA issued AD 2021-20-16, Airbus Helicopters developed a modification of the upper fin assembly. This AD requires the same actions as AD 2021-20-16 and replacement of the upper fin assembly with a modified upper fin assembly, which constitutes a terminating action for the repetitive inspections. The FAA is issuing this AD to address the unsafe condition on these products.