U.S. Air Force Senior Airman Patrick Marvel, 633rd Civil Engineer Squadron pavement and construction equipment craftsman, uses a compass during a Prime Base Engineer Emergency Force land navigation training at Joint Base Langley-Eustis, Va., June 15, 2017. During the training Airmen were provided maps, compasses and protractors to find a designated location within a one hour time limit. (U.S. Air Force photo/Airman 1st Class Kaylee Dubois)