Approach Gates
An instrument approach procedure is often described as a series of windows, or gates, extending from the final approach fix (FAF) to the missed approach point (MAP). Stay within the ever-narrowing vertical and lateral limits and youll arrive at the MAP on glide path and centered on the inbound course. Its far less common to extend this concept backward from the FAF through the terminal area to the en route environment, and forward from the MAP through the missed approach to the holding fix.