In the search mode APG-66 performs uplook and downlook scanning. Downlook uses medium PRF for target detection in heavy clutter environments. The search mode also performs search altitude display, which displays the relative altitude of targets specified by the pilot. Once a target is located via the search mode, the engagement sub-mode can be used. The OCU is designed to provide the radar with the necessary data link to perform mid-course updates of the missile.
Target acquisition can be manual or automatic in the track mode.
There are two main manual acquisition modes, single-target track and situation awareness. While in this mode, the search area does not need to include the tracked target's sector. Once a target is detected, the radar performs automatic lock-on. A boresight ACM mode is used for multiple aircraft engagement situations. This is especially useful in preventing engagement of friendly aircraft.