The 98th Operations Group is a component unit of the Nevada Test and Training Range, assigned to the United States Air Force Air Combat Command. The group is stationed at Nellis Air Force Base, Nevada.It provides day-to-day control of the Nevada Test and Training Range (NTTR) and directly supports Air Force, joint and multi-national test and training activities; and operates two Air Combat Command bombing ranges; the NTTR and Leach Lake Tactics Range, near Barstow, California.