A depth-limited Advanced V-Carving should work well – just deselect the outer geometry if you want the white areas to be lowered (figure-ground reversal is key for these designs)
Post the .c2d file if you have difficulties.
You may find:
and
- USN Masterdiver: Need help creating / editing a picture - #5 by WillAdams
- Nvy logo svg file
- Drew up a rough version of the U.S. Navy Submarine Warfare Insignia
of interest.
If you don’t have a vector see: