[TorpX]

I was never able to make any changes to ships physics with the *.cfg file. Everything I did had to be done with the *.sim file.

Like so:

mass = 2.0

surface
displacement = 0
draught = 0.3

submerged
displacement = 0
draught = 0

Imo, the submerged displacement/drafts are best left to the subs. The game does have values for the ships, but I found issues with ships not sinking if the submerged draft wasn't low enough. Setting the submerged values to zero gives the game control, and seems to work well. One can set the surface values to zero, too, but I wanted to be able to control these to correct any instability or such.

You might also check/change the put_on_water = True item.