160418-N-DN943-317 (April 18, 2016) FORT KNOX, Ky. - A U.S. Army HH-60 Blackhawk helicopter participates in a simulated medical evacuation drill with Coastal Riverine Squadron Four (CRS-4) during an annual training exercise at Ft. Knox, Ky. The coastal riverine force is a core Navy capability that provides port and harbor security, high value asset protection, and maritime security operations in coastal and inland waterways. (U.S. Navy Combat Camera photo by Mass Communication Specialist 2nd Class Gabriel Bevan/Released)