Civil service mariner Fred Walker conducts engine air intake filter maintenance in the mission bay of the Military Sealift Command’s joint high-speed vessel USNS Spearhead (JHSV 1) Jan. 22, 2015. Spearhead is on a scheduled deployment in the U.S. 6th Fleet area of operations to support the international collaborative capacity-building program Africa Partnership Station. (U.S. Navy photo by Mass Communication Specialist 1st Class Joshua Davies/Released)