If I'm reading this right you are suggesting the use of the white
masthead, while undersail alone, when in traffic or poor visibility?

If so, ....BIG NO-NO.

I must not have written my message very clearly. You are right. I
would never consider running with just the white masthead light. What
I was trying to say was that the difference between a powerboat and a
sailboat under sails alone is that the sailboat turns the white
masthead light OFF.

Have seen this rarely, and usually on a much larger sailboat (small
"Tallship". Remember it being quite distinctive, but due to rarity of
sightings, it took a few seconds to remember. (will get to usefulness
for your case later)

From what others have posted or e-mailed to me directly, the option is
pretty rare. But, if you were to see it again, because it is unusual
it probably would grab your attention. That is what I am trying to
achieve. Even if the observer didn't know what the lights meant, at
least he/she would recognize that something different was out there
and probably stay clear. And, of course, it is the big boys out there
that can do me the most harm. Professional skippers of large
commercial boats are more likely to know what the lights mean.

When you saw the lights in use where you able to see how the lights
were installed? The biggest problem seems to be how to keep them from
being blocked by the mast. It has been suggested that two lights for
each color - one on each side of the mast - be used.

To be certain, check Annex I, in the rules, but I think you'll find the
minimum to be 1M apart.

You are correct. For Truelove at 13 meters the separation is 1 meter.

G pushing it a bit. For the red over green, they are to be "at or
near" the top of the mast. However, breakdown light can be where "best
seen".

That is a very good point. So if I wanted to build a hoistable set of
lights for vessel not under command etc. I could do that, but for red
over green I would need a permanent set up, probably on the peak of
the

OK, Here's where I get confused. If you all ready have the tri-color,
why would you also want the "red over green"? I ask, because you can
only display one or the other, not both (at the same time), and that
tri-color does an excellent job .... though, admittedly, the red over
green, coupled with normal sidelights, might be better in close quarters.

If a skipper of another boat sees the red of my tricolor, for example,
he might conclude that he is seeing the starboard side of some vessel.
If he assumed that all other lights were working properly, he might
conclude that he was looking at a sailboat under sails. But a single
red light could be any number of other vessels with one or more lights
not properly functioning. If, on the other hand, he sees a red light
over a green light, there is only one type of vessel it could be - a
sailboat under sails. Also my thought is that two lights of two
different colors would be that much more visible.

You raise some good questions, the answers to which in some cases, may
come down to your own preferences and how many options you want to have
available.

Thanks for your post.

Lee Huddleston
s/v Truelove