Ahhh, and you will also find mention of 360 deg unobstructed light (above head height). So depending on local laws the mast may be the best "legal" place to put a light while sailing.
That's not to say it's the only place of course.
I was also thinking about LED lights shining back onto the sail from the AMA's. Shouldn't be able to miss the AI's sail all lit up like that. A torch could be used to do the same thing.
The white light on the mast head gives visibility at the greatest distance.
Lights on the amas, directed at the sail, would make the sail visible from a good distance. It would also, however, completely ruin any night vision you might have. You want to be seen, but you also want to be able to see. If you want to have a light shining on the sail, use one that is mounted behind you, so it's not shining into your eyes.
I use the white masthead LED light, and the red & green LED running lights mounted on the foredeck. I also keep a 3 D-cell mag light within reach. If an approaching boat does not appear to have seen me, I can shine that on the sail, or even towards the approaching craft. I've only done that once, and it turned out that they had seen me, but were curious what kind of boat I was. Go figure, even in the dark the AI draws folks in.
Happy Night Sailing,
- Jim L