U.S. Air Force Staff Sgt. John Patrick Thorpe, aerospace and operational physiologist technician from Beale Air Force Base, Calif., provides instructions to Airmen prior to their high altitude training test inside a high-altitude chamber April 4 at Offutt Air Force Base, Neb. This was the chamber’s “fini flight” as newer technology has started to replace high-altitude chambers across the Air Force. (U.S. Air Force Photo by Josh Plueger/Released)