[Sag75]

:hmm: It's depending how is modeled, anyway in RL the drag can avoid the reaching of higher speeds. The boat speed is proportional with propeller revolution, but if propeller revolution increases too much, the water/hull interaction (=drag) limits the boat to achieve higher speed. The only way to avoid it is going out from the water (i.e. plane on the water surface or use hydrofoils to emerge all the hull from water).

On the other side, the inertia is an other thing. It's the opposition by a mass body to a force. So, higher is inertia and longer is the time to achieve the speed.


Anyway, I toke a look in a random ship via S3D. If you click on "drug" in .sim file, there is a notice about drag that is expressed as F=C*V^2. I guess F is the resistance force, V squared is the ship speed, C should be a coefficent.
I saw there is a "displacement" parameter in upper position.... could be linked to inertia in your opinion??