When must an operational check on the aircraft VOR equipment be accomplished to operate under IFR?

The operational check on the aircraft VOR equipment must be accomplished within the preceding 30 days to legally operate under Instrument Flight Rules (IFR). This requirement ensures that pilots can rely on VOR navigation systems for accurate and safe navigation. Regular checks help to identify any malfunctions or inaccuracies in the VOR signals that could compromise navigational safety during flight.

While the frequency of checks may seem straightforward, it's critical to adhere to the 30-day guideline as it aligns with FAA regulations. This regulation helps in maintaining the operational integrity of the navigation equipment and prevents unexpected VOR failures that could occur if the equipment is not regularly assessed. Therefore, ensuring that the VOR equipment is functional and checked within this timeframe is essential for compliance with IFR requirements and overall flight safety.