they have missed it compleatly.
If you use metric system on the sea, you still use NM when determen travel distances. becaus the boat does Kts, not Km/h. (and for subs all targets does Kts, so torpedo speed is in Kts, but not range to target, meters or NM if determin travel time to target.)
So siplyfied it is just the deapth that is different, M instead of Ft.
Please can some one that know how to, fix it.