Air Traffic Control Systems and Procedures Practice Test

An instrument landing system is designed to guide an aircraft along a precise path to the runway, even when pilots can’t rely on visual cues. The localizer gives you accurate horizontal guidance to stay on the runway centerline, while the glide slope provides precise vertical guidance to follow the correct descent path to the threshold. Together, they ensure you are properly aligned with the runway and on a safe descent profile for landing, which is essential in instrument meteorological conditions. The other options don’t involve the ILS: weather data, flight plan data, and fuel calculations are separate functions outside what the ILS provides.