Stock Photo Description: Stock photo of Cadet 4th Class Madison Chilton performing a crawl up Spirit Hill on the U.S. Air Force Academy's Terrazzo during Recognition. Recognition marks the transition of the fourth classmen to upper class status. It is the ceremonial acknowledgement that the fourth class has successfully met the training requirements expected of it, and is prepared to continue its four-year journey through the Academy. (U.S. Air Force photo/Mike Kaplan). Stock photography by Department of Defense Public Domain.