What is required for a vessel to take early and substantial action to avoid a collision?

Taking early and substantial action to avoid a collision is primarily the responsibility of the give way vessel. The give way vessel is the one required to yield to the other in order to prevent a potential collision. This responsibility involves actively maneuvering the boat, which could include changing speed or direction, so that the stand on vessel can maintain its course and speed.

In the context of navigation rules, the give way vessel must be vigilant and take necessary measures whenever a situation arises that may lead to a collision, while the stand on vessel typically has the right of way and can assume the other vessel will act appropriately to avoid a collision. Thus, understanding the roles of give way and stand on vessels is essential for boat operators to ensure safety on the water.