Abstract: Actuation apparatus for linearly engage and disengage pins respectively disposed along two predetermined (orthogonal) axes using a single actuator. The actuation apparatus comprises a housing and the actuator, which may comprise a DC torquer motor disposed in the housing. The actuator or motor has a threaded rotary shaft. A common plunger is coupled to the threaded rotary shaft that has an elevation ramp formed therein. Azimuth and elevation actuation pins are disposed along the predetermined axes within the housing that are moveable and extend outside the housing and retract into the housing when selectively actuated. Azimuth and elevation springs are disposed around the azimuth and elevation actuation pin. In a preferred embodiment, the pins are extendable into and removable from slots disposed in a moveable gimbal of a missile seeker, and locks an antenna disposed on the gimbal.