EASA AD 26-121
Equipment / Furnishings – System Interface Unit – Replacement
EASA Airworthiness Directive Proposal 26-121 is a regulatory document addressing the replacement of the System Interface Unit (SIU) on Airbus Helicopters Deutschland GmbH MBB-BK117 D-2 (except D-2m variant) and D-3 helicopters. The directive applies to SIU Manufacturer Part Number 503-24-6-G installed on helicopters with serial numbers 20001 to 20360 and 21001 to 21999. It aims to ensure continued airworthiness by mandating replacement of affected SIUs based on their time since manufacture or last overhaul.
Airworthiness DirectiveMaintenanceSafety MgmtAirbus Helicopters MBB-BK 117Airbus Helicopters MBB-BK 117 D-2Airbus Helicopters MBB-BK 117 D-3Airbus Helicopters MBB-BK117 D-2Airbus Helicopters MBB-BK117 D-3