I want to be sure of the mast height on my 2007 423 before I venture out on an ICW route. Anyone have experience confirming their mast height and if so how did you confirm. Use a halyard? tape measure? then how did you confirm down to the water line. Thanks
Beneteau 423 Mast height measurement
- Thread starter Riverdaze
- Start date
We have two issues here in the PacificNW. Bridges and tidal change.
You have the same issues. Knowing the Bridge clearance and the tide level is critical to safe passage.
Your boat is a fractional rig, with a "Deck Stepped Mast".
I measured my mast (also deck stepped) by running a tape up to the mast head using my main halyard and stretching the tape to the deck. That gave me the approximate length of the mast. I then went to the baot's side and measured the distance from the mast base to the water line. Knowing that most VHF wire antenna's run about 3 ft I added that to the number. Then I added a 2 ft safety fudge factor to the calculations. On my boat this worked out to an air-draft of 52ft.
You can also go to the Beneteau Manual and find:
X) SPECIFICATIONS OF THE BOAT
Clearance Height 54.36 ft
This does not likely include added hardware on the top of your mast (wind speed transducer, VHF Antenna, etc.).
Just being the doubter I am I would do my own measurement and add a fudge factor.
You have the same issues. Knowing the Bridge clearance and the tide level is critical to safe passage.
Your boat is a fractional rig, with a "Deck Stepped Mast".
I measured my mast (also deck stepped) by running a tape up to the mast head using my main halyard and stretching the tape to the deck. That gave me the approximate length of the mast. I then went to the baot's side and measured the distance from the mast base to the water line. Knowing that most VHF wire antenna's run about 3 ft I added that to the number. Then I added a 2 ft safety fudge factor to the calculations. On my boat this worked out to an air-draft of 52ft.
You can also go to the Beneteau Manual and find:
X) SPECIFICATIONS OF THE BOAT
Clearance Height 54.36 ft
This does not likely include added hardware on the top of your mast (wind speed transducer, VHF Antenna, etc.).
Just being the doubter I am I would do my own measurement and add a fudge factor.
Thank you for your reply. I too see mast height is 54.36 in the manual and see a number of listings state 54' mast height. The listing I purchased my boat from however stated 63' mast height, ICW friendly. To clear up my confusion and feel more comfortable, I will run a line up using the spare halyard, and measure the line. . If I measure 54' from the deck then I air draft will be closer to the 63' not including the 18" VHF antennae. I looked at a number of 423"s listed and many state 54' bridge clearance. Also I looked at the manual and the "I" measurement is 48' so I am pretty sure I have a 54' air draft plus a few feet of masthead accessories. I think the halyard technique alone will suffice to verify 54' vs 63'.
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I like it. Trust but verify. A solid plan.
It doesn’t make it easier when heading down stream towards a bridge and you know that the tide waters are running full. I still aim for the area of the bridge with the most apparent space.
It does give you an opportunity to mess with your Brother in Law. Talking about the risk of the bridge.
What of you think, will we make it?
I think I’ll slow down and we will creep up on the bridge. If you go to the bow, maybe you can better judge the problem.
Yes lay down and use your arm to get the angle of the mast and the bridge bottom. I don’t know. Oh hell in for a penny in for a pound. Full speed and damn the bridge. Hold on.
It doesn’t make it easier when heading down stream towards a bridge and you know that the tide waters are running full. I still aim for the area of the bridge with the most apparent space.
It does give you an opportunity to mess with your Brother in Law. Talking about the risk of the bridge.
What of you think, will we make it?
I think I’ll slow down and we will creep up on the bridge. If you go to the bow, maybe you can better judge the problem.
Yes lay down and use your arm to get the angle of the mast and the bridge bottom. I don’t know. Oh hell in for a penny in for a pound. Full speed and damn the bridge. Hold on.
Oh you ship head. I’m going to tell my sister what you did. 
I like that scenario and will use it. ALready had my Brother in Law on our Catalina 36 in San Diego Harbor. We left a restaurant across the bay on Coronado at night and the winds picked up. We were healing across the bay. Had one chance to swing into our Harbor Island slip without catching windward beam to push us against the opposite dock pilings. Motored into a starboard turn right into our slip against the wind and he was plastered against the forward cockpit wall breathless.