EASA AD 2021-0031
Tail Rotor Drive — Gearbox Assembly — Replacement
Summary
EASA Airworthiness Directive 2021-0031 is an airworthiness directive addressing the replacement of tail rotor gearbox assemblies on Leonardo S.p.A. A109E helicopters. It applies to all A109E helicopters with serial numbers up to 11160 inclusive and targets specific tail rotor gearbox part numbers that are not approved for installation on these helicopters. The directive mandates replacing affected tail rotor gearbox assemblies with approved serviceable parts to ensure continued airworthiness.
What Changed
EASA Airworthiness Directive 2021-0031 introduces a mandatory replacement of tail rotor gearbox assemblies having part number 109-0440-01-115 with serviceable parts having part numbers 109-0440-01-119, 109-0440-01-121, or 109-0440-01-123. It also prohibits the installation or reinstallation of the affected parts on any A109E helicopter. This is a new directive and does not supersede any previous ADs.
Why It Matters
This directive is critical for aviation professionals because the affected tail rotor gearbox assemblies are not approved for use on A109E helicopters and lack published overhaul or life limits, posing a risk of failure. Failure of these parts could lead to reduced helicopter control, impacting flight safety. Operators, maintenance organizations, and compliance teams must ensure timely replacement to maintain airworthiness and regulatory compliance.
What To Do
Operators of A109E helicopters with affected tail rotor gearbox assemblies must replace these parts with approved serviceable parts within specified flight hour or calendar time limits, generally within 25 flight hours or 3 months for parts with higher flight hours, or within 50 flight hours or 6 months for others, whichever occurs first after 5 February 2021. Additionally, no affected parts may be installed on any helicopter from the effective date onward. Compliance must follow Leonardo Alert Service Bulletin 109EP-174 instructions.
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