Which system is primarily responsible for guiding aircraft during the landing phase?

The Instrument Landing System (ILS) is primarily responsible for guiding aircraft during the landing phase. This system provides precise lateral and vertical guidance to pilots as they approach the runway, ensuring safe landings even in poor visibility conditions. The ILS typically includes a localizer that helps with horizontal alignment to the runway and a glideslope that provides vertical descent information.

While the other systems mentioned play important roles in aviation, they do not serve the primary function of guiding aircraft during landing as effectively as ILS does. For instance, the Glidescope offers vertical guidance but is part of the ILS system itself. The Precision Approach Path Indicator (PAPI) provides visual cues to help pilots maintain the correct approach angle during landing, but it does not provide the same level of precision that ILS does. Distance Measuring Equipment (DME) is used for measuring the distance to the aircraft from a specific point along the approach but does not assist with the actual landing guidance.

Understanding these distinctions highlights the critical role that ILS plays in ensuring safe and accurate landings, especially in challenging weather situations.