Which rules apply when visibility is poor for pilots?

When visibility is poor, pilots are required to follow Instrument Flight Rules (IFR). IFR provides protocols for flying in conditions where visual navigation is not possible, which is typically due to low visibility, such as clouds, fog, rain, or nighttime conditions. Under IFR, pilots rely on instruments for navigation and must adhere to specific air traffic control instructions to ensure safe operation.

Flying under IFR ensures that pilots maintain appropriate altitudes, communicate with air traffic control, and use navigation aids such as GPS and radio signals. This system is designed to manage air traffic in less-than-ideal conditions and enhances safety by providing structured guidelines for pilots to follow.

In contrast, visual flight rules (VFR) are appropriate when visibility is good and pilots can safely navigate by sight. Night Flight Rules apply specifically to operations conducted after sunset and do not necessarily address poor visibility conditions, while Emergency Flight Rules are implemented during unexpected situations that require immediate action, which does not relate directly to the usual operational procedures based around visibility.