EASA AD 2024-0209
Tail Rotor — Hub Body — Inspection / Replacement
Summary
EASA Airworthiness Directive 2024-0209 is an airworthiness directive addressing the inspection and replacement of the tail rotor hub body on Airbus Helicopters EC 120 B helicopters. It applies to all serial numbers and focuses on Part Number C642A0100103, the tail rotor hub body, and its interface with the splined flange. The directive mandates inspections to detect cracks and fretting, replacement of affected parts, and a modification involving marking bolts and nuts with red paint.
What Changed
EASA AD 2024-0209 supersedes the previous AD 2021-0069 and retains its inspection and replacement requirements while introducing a new modification that requires adding a line of red paint on each bolt and nut linking the tail hub and splined flange. This modification serves as a terminating action for repetitive inspections and replacements. The directive also updates compliance intervals and inspection procedures based on the latest service bulletins.
Why It Matters
This directive is critical for maintaining the safety and airworthiness of EC 120 B helicopters by preventing loss of tail rotor drive and potential loss of yaw control due to cracks caused by loss of bolt tightening torque and fretting. Operators, maintenance organizations, and compliance teams must adhere to these requirements to avoid unsafe conditions and ensure regulatory compliance. The directive also streamlines maintenance by providing a terminating modification that reduces repetitive inspection burdens.
What To Do
Operators must inspect the tail rotor hub body within 15 flight hours or 7 days after 1 November 2019 and continue inspections at intervals not exceeding 15 flight hours. Detailed inspections of the interface with the splined flange must be done concurrently with bolt replacements and every 1,000 flight hours thereafter. Bolts, washers, and nuts must be replaced within specified compliance times, and within 24 months of the AD's effective date, operators must apply red paint markings on bolts and nuts as per the modification service bulletin. Compliance with corrective actions and replacement instructions is mandatory before further flight if defects are found.