190517-N-YM590-1019 MASSACHUSETTS BAY (May 17, 2019) Sailors assigned to the Knifefish unmanned undersea vehicle (UUV) test team man tending lines during crane operations of the Knifefish UUV after a mission as part of an operational test conducted by members from Operational Test and Evaluation Force (OPTEVFOR). Knifefish is a medium-class mine countermeasure UUV designed for deployment off the Littoral Combat Ship. OPTEVFOR is the Navy’s sole test and evaluation organization for surface, air, and undersea warfare, along with various other programs which impact the Navy’s overall mission. (U.S. Navy photo by Mass Communication Specialist 1st Class Brian M. Brooks/RELEASED)