The 128th Air Control Squadron (ACS) is a unit of the Wisconsin Air National Guard based at Volk Field Air National Guard Base. Originally established as the 128th Aircraft Control and Warning Squadron in 1947 at General Billy Mitchell Field, it was subsequently re-designated as a Control and Reporting Post, and a Forward Air Control Post-Heavy. In October 1991, the unit was transferred to its current base as the 128 Air Control Squadron. The 128th ACS may be deployed world-wide to provide tactical air control, data links, and data transfer in the Theater Battle Management arena.