Re: Boating 101+3 - ANSWER
18 rabbit. It is an absolute. The configuration and type of lights displayed is what lets others know how big your boat is and what kind of activity you are engaged in. i.e. sailing, trolling, trawling, piloting, search and rescue, towing, not under command, etc. etc... (red over red, the pilot is dead / red over green sailing machine, and so on. That's how I learned them anyway.) Most work boats have mulitple configurations to utilize depending on what they are doing. The only variance I can think of is this. Vessels under 16' in length not under power i.e. rowboat, canoe, etc. are required to display a flashlight only, however they may also display 225 degrees forward facing split red and green and 135 rear facing white. There may be other isolated exceptions, but I cannot think of any. Remember this is for Nav Lights only, of course you can have other non-navigation lights on your boat.
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