What is the purpose of an Instrument Landing System (ILS)?

The purpose of an Instrument Landing System (ILS) is specifically to guide aircraft during landing in low visibility conditions. ILS provides precise guidance to pilots by using a combination of radio signals and high-precision approach aid. It consists of two main components: the localizer, which helps in horizontal guidance for aircraft to align with the runway centerline, and the glideslope, which gives vertical guidance to ensure the aircraft descends at the appropriate angle during approach and landing.

This system is critical in situations where weather conditions such as fog, rain, or snow significantly reduce visibility, making it difficult for pilots to land safely using visual references alone. By relying on the ILS, pilots can confidently navigate their approach using instruments, ensuring a safer landing process under challenging conditions.

The other options provided do not align with the primary function of the ILS. While takeoff, flight weight balance calculations, and mid-flight navigation are essential aspects of aviation, they do not involve the direct application of an Instrument Landing System designed for landing procedures.