A three-dimensional permissive fire support coordination measure used to facilitate integration of fires is referred to as what?

The term that describes a three-dimensional permissive fire support coordination measure used to facilitate the integration of fires is a Kill Box. A Kill Box provides a designated area where units can conduct fires on targets without needing further coordination, as long as they adhere to certain pre-established guidelines and rules of engagement. This designation allows for rapid execution of fire missions and enhances the efficiency of fire support while minimizing the risk of friendly fire incidents. The three-dimensional aspect indicates that it encompasses not just horizontal space but also the vertical space in the air, allowing aircraft and ground forces to operate within it without the need for further approval for engagement against enemy forces.

In contrast, the other options refer to different categories or types of control measures. An Airspace Coordination Area typically focuses on managing and coordinating airspace use to prevent conflicts between air and surface operations. A Free Fire Area designates an area where any unit may engage targets without any restriction, but it may still entail certain limitations and requires pre-combat coordination. A No Fire Area, on the other hand, prohibits any fire support within its boundaries, which is the opposite of what a Kill Box facilitates. Thus, the Kill Box stands out as the most fitting choice for this particular question regarding permissive fire support coordination measures.