Bomber “box” formations allowed guns in each aircraft to protect vulnerable blind spots on the other airplanes in the group. The formation was vital for defense. Assembly Ships were older aircraft, usually having completed their schedule of active sorties, which were painted in bright colors and patterns to be highly visible. As bombers launched from their many fields they would line up behind these Assembly Ships to create their formations. (Consolidated-B-24 Liberator)
https://flic.kr/p/etXqSz | Planes of Fame Air Show 2013 - Consolidated PB4Y-2 Privateer; BuNo 66302, N2871G | Consolidated PB4Y-2 Privateer; BuNo 66302, N2871G, departing Chino Airport, Chino, California after the 2013 Planes of Fame Airshow. This aircraft was on static display during the airshow.