U.S. Air Force 1st Lts. Andrew Crispin and Emily Barkemeyer, C-17 Globemaster III cargo aircraft student pilots, run through the C-17 pre-flight checks in the flight simulator, Sept. 16, 2014. Students spend 136.5 hours in the simulators, the majority of the C-17 pilot course. Simulators operate at five percent of the cost of a real aircraft, saving a substantial amount of money. (U.S. Air Force photo by Airman 1st Class Nathan Clark/Released)