EASA AD 2018-0066
SUPERSEDED BY EASA AD 2020-0022
Summary
EASA Airworthiness Directive 2018-0066 is an airworthiness directive issued by the European Aviation Safety Agency affecting Airbus Helicopters AS 332 L, L1, C, and C1 models. It addresses the inspection and replacement of certain second stage planet gear assemblies in the main gearbox to prevent failure due to higher outer race contact pressures. The directive mandates repetitive inspections and replacement of affected parts to ensure continued safe operation.
What Changed
This directive introduces mandatory repetitive inspections of the main gearbox particle detectors and requires identification and replacement of affected second stage planet gear assemblies with serviceable ones. It also prohibits installation of main gearboxes equipped with the affected planet gears from the effective date. These measures align the AS 332 helicopter fleet with safety standards previously applied to the EC 225 LP/AS 332 L2 models.
Why It Matters
This directive is critical for aviation professionals because it addresses a known failure mode in the main gearbox that could lead to catastrophic helicopter failure. Operators and maintenance organizations must comply to ensure aircraft safety and regulatory compliance. The directive helps prevent in-flight failures by enforcing early detection and removal of susceptible components.
What To Do
Operators must inspect the main gearbox particle detectors within 10 flight hours of the directive's effective date and every 10 flight hours thereafter. If particles are detected, they must be analyzed and corrective actions taken before further flight if limits are exceeded. Additionally, within 50 flight hours, the part numbers of second stage planet gears must be identified and affected gear assemblies replaced with serviceable ones. Installation of affected main gearboxes is prohibited from the effective date onward.
Your fleet's weekly compliance brief
AI-summarized regulatory changes, compliance deadlines, and action items — filtered to your aircraft, every Monday.
AI-generated summary from official EASA source document. Always verify against the original.