U.S. Air Force Senior Airman Mason Wyman, 633rd Aerospace Medical Squadron physiology technician, tests a new Reduced Oxygen Breathing Device at Langley Air Force Base, Va., Dec. 11, 2014. Unlike the hypobaric chamber, the ROBD simulates flights on a digital screen, which a pilot would operate while experiencing hypoxia. (U.S. Air Force photo by Airman 1st Class Devin Scott Michaels/Released)