The 504th Expeditionary Air Support Operations Group is an active United States Air Force unit. It was first activated in 1966 for service during the Vietnam War, and was reactivated in 2009 for service in Afghanistan.In Vietnam the group provided combat ready aircraft and crews in support of air and ground operations in Southeast Asia (SEA); conducted visual reconnaissance and convoy escort; trained Air Liaison Officers (ALO) and Forward Air Controllers (FAC), 1966–1972.