Main Rotor Drive — Main Gearbox — Replacement
- Published
- Effective
- Deadline
AI-generated summary of the official EASA document. Verify against the PDF before acting.
What to do
Operators of EC 155 B and B1 helicopters with affected main gearboxes must replace these gearboxes within 10 flight hours or 75 days from 16 March 2020, whichever occurs first. All operators must also ensure that no affected main gearboxes are installed on any helicopter from the effective date onward. Compliance must follow the instructions detailed in Airbus Helicopters Alert Service Bulletin EC155-63A020.
Summary
EASA Airworthiness Directive 2020-0043 is an airworthiness directive issued by the European Union Aviation Safety Agency concerning Airbus Helicopters EC 155 B and EC 155 B1 models. It addresses the replacement of main gearboxes (MGB) with specific part numbers and serial numbers due to potential manufacturing inspection errors. The directive mandates actions to ensure continued safe operation of affected helicopters.
What changed
This new airworthiness directive requires the replacement of affected main gearboxes identified by certain part and serial numbers with serviceable units. It prohibits the installation or reinstallation of these affected main gearboxes on any EC 155 helicopter. The directive introduces mandatory compliance within a specified timeframe to mitigate the risk of gearbox failure.
Why it matters
This directive is critical for aviation professionals because it addresses a potential safety risk from incorrectly evaluated non-destructive tests on main gearbox housings. Failure to comply could lead to gearbox failure and reduced helicopter control, posing serious safety hazards. Operators, maintenance organizations, and compliance teams must ensure timely replacement and avoid installation of affected parts to maintain airworthiness.
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