Microwave landing system
![The NASA 737 research aircraft on the Wallops runway in 1987 with the Microwave Landing System equipment in the foreground.](/Images/godic/202501/27/P41a1109.JPG")
![An MLS azimuth guidance station with rectangular azimuth scanning antenna with DME antenna at left.](/Images/godic/202501/27/MLS_Azimuth_Guidance1109.jpg")
![An MLS elevation guidance station.](/Images/godic/202501/27/MLS_Elevation_Guidance1110.jpg")
![FIG 1-1-10 Coverage Volumes 3-D Representation](/Images/godic/202501/27/Microwave_Landing_System.svg1110.png")
A microwave landing system (MLS) is an all-weather, precision landing system originally intended to replace or supplement instrument landing systems (ILS). MLS has a number of operational advantages, including a wide selection of channels to avoid interference with other nearby airports, excellent performance in all weather, a small "footprint" at the airports, and wide vertical and horizontal "capture" angles that allowed approaches from wider areas around the airport.