What is the typical course width of a Localizer?

The typical course width of a Localizer is indeed 3°-6°. The Localizer is a key component of the Instrument Landing System (ILS), providing lateral guidance to pilots as they approach a runway. The width of the Localizer signal is crucial as it ensures that aircraft remain on the correct flight path during the final approach phase.

A narrower course width allows for more precise alignment with the runway, which is particularly important in conditions of low visibility. The chosen range of 3°-6° strikes a balance between providing sufficient lateral guidance while also allowing for some margin for error in the aircraft’s approach. This course width helps to reduce the likelihood of course deviation during critical phases of flight.

In practice, this means that pilots need to maintain their aircraft within this narrow band to successfully intercept and follow the Localizer signal to touchdown. The wider the signal, the more room there is for error, which may not be ideal during the final stages of an approach, where precision is paramount.