Sailors assigned to Coastal Riverine Group (CRG) 1 explain the Unmanned Aircraft System to Rear Adm. Brian Brakke, center, commander of Navy Expeditionary Combat Command, during NMCB 4's field training exercise (FTX).

FORT HUNTER LIGGETT, Calif. (May. 16, 2017) Sailors assigned to Coastal Riverine Group (CRG) 1 explain the Unmanned Aircraft System to Rear Adm. Brian Brakke, center, commander of Navy Expeditionary Combat Command, during NMCB 4's field training exercise (FTX). The FTX prepares and tests the battalion's ability to enter hostile locations, build assigned construction projects and defend against enemy attacks using realistic scenarios while being evaluated by Naval Construction Group 1. (U.S. Navy photo by Utilitiesman 2nd Class Jasmine Flores) File# 170516-N-XJ502-058