For which kind of flights is IFR predominantly used?

Instrument Flight Rules (IFR) are primarily utilized in situations where visibility is reduced, such as during poor weather conditions, fog, or when flying at night. The use of IFR allows pilots to navigate and control the aircraft safely using instruments when visual references to the ground or horizons are not available. This is especially important in controlled airspace, where air traffic control (ATC) provides guidance to ensure safety and separation between aircraft. In these scenarios, it is critical for pilots to rely on instruments rather than visual cues, making IFR the standard operating procedure.

Commercial and charter flights might sometimes operate in clear weather under Visual Flight Rules (VFR), which require good visibility and distance from clouds. However, IFR is particularly integral to ensuring safety during challenging flying conditions, underscoring why it is predominantly associated with flights operating in reduced visibility.