170112-N-PO203-226_(32609261285)

Rear Adm. David Hahn, chief of naval research, assists with loading a Hyper Velocity Projectile (HVP) into a traditional powder gun at the Naval Surface Warfare Center, Dahlgren Division, Virginia. Photo: US Navy / John F. Williams

September 12, 2017 10:47 AM (UTC+8)