Here is the closest link I could find, it’s mentioned
some where in this file. This research was in the 2005s
and I seen nothing current, so maybe they spent millions
and it didn’t work, or maybe it did and has gone dark.
This was to be a piloted underwater craft comparable to
a jet fighter, they were experimenting with something
called a “Vortex” drive, but now there is nothing.
N a r r a t i v e T i t l e FY 2003 FY 2004 FY 2005 Loki / Mobile Undersea Distributed Systems 3.945 0.000 0.000 (U) The...Loki program evaluated technologies that had the potential to enable a revolutionary “fighter-like” submersible to counter the asymmetric threat posed by diesel submarines and other forces operating...
https://www.darpa.mil/attachments/(2G12)%20Global%20Nav%20-%20About%20Us%20-%20Budget%20-%20Budget%20Entries%20-%20FY2005%20(Approved).pdf
Thank you sir, I appreciate that