Navy SEAL SDV mini submarine.



3:15 video:



More: https://theaviationist.com/2019/11/0...e-shadowy-sdv/

Previously:

U.S. Navy submarine missile launch tubes - photo
Narco-submarine captured by U.S. Coast Guard - video and infographic
Submarine drone captures lionfish - video
Submarine cutaway - photo
steam-powered submarine
The H.L. Hunley, the first submarine to sink a warship