Col. Stephen Langford, Nevada Test and Training Range commander, speaks to members of his organization during the NTTR assumption of command ceremony, Jan. 28, 2013, at Nellis Air Force Base, Nev. The NTTR is the largest contiguous air and ground space available for peacetime military operations in the free world. The range occupies 2.9 million acres of land, 5,000 square miles of airspace, which is restricted from civilian air traffic over-flight, and another 7,000 square miles of military operating area, which is shared with civilian aircraft. (U.S. Air Force photo by Senior Airman Matthew Lancaster)