Tail Rotor Drive — Tail Gear Box — Inspection / Replacement
- Published
- Effective
- Deadline
AI-generated summary of the official EASA document. Verify against the PDF before acting.
What to do
Operators of MBB-BK117 A-1, A-3, A-4, B-1, B-2, C-1, and C-2 helicopters must inspect the tail gear box bellcrank attachment arm within 100 flight hours from 2018-03-05, following the Airbus Helicopters Alert Service Bulletin instructions. If any cracks or anomalies are detected, repair or replace the TGB before the next flight. Only install TGBs that have passed the inspection from the effective date onward.
Summary
EASA Airworthiness Directive 2018-0046 is an airworthiness directive issued by the European Union Aviation Safety Agency concerning Airbus Helicopters Deutschland GmbH MBB-BK 117 series helicopters. It mandates inspection and possible replacement or repair of the tail gear box (TGB) bellcrank attachment arm on affected MBB-BK117 A-1, A-3, A-4, B-1, B-2, C-1, and C-2 helicopters to address detected cracks. The directive applies to TGB parts with specific part numbers and aims to prevent potential loss of helicopter control.
What changed
This new airworthiness directive introduces mandatory inspections of the tail gear box bellcrank attachment arm within 100 flight hours after the effective date. If cracks or anomalies are found, the directive requires immediate corrective actions including repair or replacement of the TGB before further flight. It also restricts installation of TGBs to only those that have passed the required inspection.
Why it matters
This directive is critical for aviation professionals as it addresses a safety risk that could lead to loss of helicopter control due to disconnection of the bellcrank attachment arm. Operators and maintenance organizations must ensure compliance to avoid potential accidents and regulatory penalties. The directive ensures continued airworthiness and safety of the MBB-BK117 helicopter fleet by enforcing timely inspections and corrective measures.
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