Join Date: Oct 2007
Thanked 70 Times in 61 Posts
Rep Power: 10
Re: Rule 23a question
(c | d) (i) A power-driven vessel of less than 12 meters in length may in lieu of the lights prescribed in paragraph (a) of this Rule exhibit an all-round white light and sidelights.
So your motoring back to the slip and your mast head light goes out.
As long as navigation lights are working just flip on your anchor light and pop the bulb out of your stern light and you are legal.