The United States Army Air Force (USAAF) trained its field maintenance crews in camouflage painting to make aircraft difficult to distinguish from the ground. Constructed in the spring of 1943, this building was designed for teaching and facilitating aircraft camouflage techniques. A catwalk, unique among Lewistown Airfield’s buildings, allowed students to lay out their designs and provided instructors a bird’s eye view to evaluate them. While American allies used elaborate camouflage, USAAF heavy bombers never widely adopted it. This building more frequently functioned as an auxiliary hangar for base utility aircraft shuttles that carried payroll and mail between Lewistown and the main base at Great Falls. It also may have housed the small twin engine AT-6 “tug” used in target practice. The plane towed a windsock-like target over the gunnery range north of Grass Range. The B-17 gunners fired painted, color-coded bullets so the instructor could determine who hit the target. Vintage pinup posters and calendars decorate the “camo” building’s main walls, colorfully recalling the years the building saw active use.