When does a sailboat need to follow navigation rules for a powerboat?

A sailboat must follow navigation rules for powerboats when it is under power (using its engine) rather than sailing. Additionally, when a sailboat is operating in a situation where it is overtaking or crossing paths with a powerboat, it must adhere to the same navigation rules to avoid collisions. It's important for all vessels to be aware of and comply with the relevant maritime rules to ensure safety on the water.