Senior Master Sgt. Jim Masura conducts pre-flight checks on his C-17 Globemaster III during Operation Deep Freeze Aug. 20 at Pegasus Runway in Antarctica. A C-17 and 31 Airmen from McChord Air Force Base, Wash., began the annual winter fly-in augmentation of scientists, support personnel, food and equipment for the U.S. Antarctic Program at McMurdo Station. WinFly is the opening of the first flights to McMurdo Station, which closed for the austral winter in February. (U.S. Air Force photo/Tech. Sgt. Shane A. Cuomo)