Mast height above water

Oct 19, 2017
7,733
O'Day 19 Littleton, NH
Welcome to SBO, Thedroubies.
You have come to the right place for all things sailing. You obviously have a great sense of good sailing to make this decision for answers to your questions.
Others who know a lot more than I will be along to help. In the mean time, I would suggest two immediate solutions. One, as a former Maths teacher and design engineer, trigonometry. The other, run a 50' tape measure up your halyard and add the distance from water plus a foot for the mast head and weather vane to the measurement. That should get you pretty darn close.

It is great to welcome you aboard and good luck and good weather.

-Will (Dragonfly)
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
If you are nerdy, you could build a simple klinometer like this out of a PVC pipe and a simple protractor. You look through the pipe at the top of your mast, place your finger on the string to hold the position, then look at the protractor for your angle.
1565962588382.png
or
1565963312707.png
... part "A" would be a level.

and then use this equation and process

1565962699462.png


If you are standing on a dock, then "h" would be the height of your eye above the dock plus the height of the dock above the water. You can probably find the mast length on this forum but if you have antenae etc. on top of your mast and/or your water line is a little different than the average... this process will allow you to find the exact mast height. Add 6" for a buffer and you can feel safe crossing under a bridge.
 
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Likes: Will Gilmore
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
Did Hunter make a 31 in 2008? I thought it was between '83 and '87. Anyway, the 31 had a mast height of 47' above DWL.
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
This link is for an H33. The OP said he had an H31. @Brian D 's question might be the key here. :rolleyes:

According to this link, they stopped making the 31 in 1987
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
@Hello Below
According to this link, Hunter was making the H33 in 2008
 
Feb 17, 2006
5,274
Lancer 27PS MCB Camp Pendleton KF6BL
It appears that Hunter did make a 31 in 2006. It was the H31-2 but prior to 2006 it was the H30. Appears to be the same boat. Mast height above DWL is 44'.