When does a ship "raise its hull"?

Question

When does a ship "raise its hull"?

Answer 1

when it goes fast enough, the bow rises out of the water.

Answer 2

just before it planes out... the bow rises at take off and sits down at cruising speed.

Answer 3

Any time the ship begins to move forward the bow will raise in resistance to the water it is pushing through until such time the desired speed is reached, then it will settle some this is called planning out, but it will not fully drop to it's normal waterline until stopped again.