U.S. Army Spc. Mclenzy Bristow, 757th Expeditionary Rail Command railway planning and advisory team member, measures the distance between rail ties during a training course at Joint Base Langley-Eustis, Va., Oct. 4, 2016. Railway planning and advising are part of a new rail field, which was consolidated from three previous railroad specialties in 2015. (U.S. Air Force photo by Staff Sgt. Natasha Stannard)