U.S. Air Force Lt. Col. Thomas Blake, 157th Air Refueling Wing pilot, and Lt. Col. Daniel Stone, 64th Air Refueling Squadron pilot, from the 22nd Air Refueling Wing out of McConnell Air Force Base, Kansas, fly a KC-135 Stratotanker during Red Flag 13-2 Jan. 25, 2013, above the Nevada Test and Training Range. The KC-135, which entered service in 1957, is one of six military fixed-wing aircraft with more than 50 years of continuous service. The KC-135’s provides the core aerial refueling capability for the U.S. Air Force. (U.S. Air Force Photo by Airman 1st Class Jason Couillard/Released)