R of R Basics ------ Page 3 of 10
When you see the red side light of another vessel, that means you are the Give Way vessel and should either turn to starboard (right) and pass their stern or slow down.
The red and green side lights have an arc of visibilty of 112.5 degrees from the bow leading aft. If a vessel can see your own ship's side light it is most likely what the rules refer to as a crossing situation.
