The FFM-1 is a five element Yagi array antenna used primarily for monitoring the signal of a localizer array used in air navigation instrument landing systems.
The antenna consists of a rectangular aluminum support boom with two driven elements, one parasitic reflector, and two parasitic directors mounted to it. The driven elements are folded dipole designs giving broadband performance over the 108-112 MHz range. The optional antenna support is designed for FAA frangibility requirements. The antenna is designed to mount to a 2-1/2″ IPS pipe.