"Red" Mast light ?

[Recovery Room]

Just curious, I was out at Martha's Vineyard last week and saw a sailboat (a very large sailboat) that had a red mast light. I'd guess it was between 80' and 100' and the mast was much higher than any of the other boats around. It also had a more traditional white light on the rear mast (it was a ketch) as well as on the first spreader down from the top.

Though it sounds foolish, the only thing I could think of was that it was a warning for aircraft as that sucker was pretty tall. Does anyone know?

[ReelWork]

Could be for bridge clearance markers? But I dunno....

[mole2]

Take a look on this page under sailing vessels and vessels under oar. You'll see a red/green or red/green/white mast light are of the types used on vessels under 20 meters.

http://www.boatsafe.com/nauticalknow...ting/4_2_b.htm