Senior Airmen Jess Evans, Detachment 1, 66th Training Squadron, Arctic Survival School Instructor, demontrates a water machine to a class attending Arctic Survival School Feb. 25 at Eileson Air Force Base, Alaska. A water machine melts snow in a sea anchor or other improvized device, then water is collected in a container. (U.S. Air Force photo/Airman 1st Class Willard E. Grande II)