What is the period within which a pilot-in-command must pass a check of route and aerodrome proficiency under CAR Part 135?

The requirement for a pilot-in-command to pass a check of route and aerodrome proficiency under Civil Aviation Rules (CAR) Part 135 is set at 12 months. This timeframe aligns with the regulations that ensure pilots maintain a current understanding of specified routes and aerodromes, which is crucial for safety and operational integrity. By requiring this proficiency check every 12 months, it helps ensure that pilots are up to date with any changes in routes, procedures, or aerodrome layouts. This regular evaluation supports the competency of pilots operating under this part of the regulation, ultimately contributing to safer aviation operations. The other timeframes such as 6, 18, and 24 months either do not meet the established standard or exceed the necessary frequency for maintaining proficient operational capability.