Summary: The Air Force has greatly overestimated the number of airfields worldwide that can accommodate the wide-bodied, C-17 cargo plane; when runway strength is considered, the C-17's wartime advantage over its C-5 predecessor shrinks from 6,400 to about 900 airfields. The C-17 advantage dwindles even further when only airfields that have been determined by the Air Force to be suitable for military operations are considered. So far, the Air Force has surveyed about 2,800 airfields as suitable for military operations. When wartime landing requirements, including minimum runway strength, are considered, the C-17's wartime airfield advantage is 145. When airfields in the United States, Canada, and Mexico are excluded, the C-17's wartime advantage falls to 95 airfields. Although the Air Face claims that the C-17's ability to land at small, austere airfields during wartime is a significant military advantage, the Defense Department has identified only three such airfields that the C-17 would use in major regional contingency scenarios; two are in Korea and one is in Saudi Arabia.