How to get an 80' tall sailboat under a 65' tall bridge

The bride on the Okeechobee Waterway near Indian Town is 49 feet, and there barrels and other devices which are used regularly to heal sailboats over to get the bridge at tis max hight. These water bags have been used by some boats for going up and down the ICW. But--it is risky--and 80 feet under a 65 foot bridge is a fair amount. (I didn't do the math), but I would prefer to go outside...As recollect there was one one boat which lost the bags when under a bridge--not a good situation!

Most ICW bridges are 65 feet--a few are 70 feet. There are still some on the Gulf Coast which are 50 fee.
 
Actually it looks like simple physics and trigonometry to me. I'd do it with my sailboat, too, as long as I was certain of no big powerboat wake coming along.

65 ft vs 80 ft would be a 36 degree heeling angle, by the way. Not a big deal.

If it started to heel too far, the water would unload the force on the bag and the boat should be stable right there. The only problem then would be steering with the drag on the bag way off to the side. That would be impossible. I'd think you'd want to be going pretty slow if it had a chance of touching down. I could see adding a couple of spring lines forward and backward from the bag for stability. It looked pretty steady, though.

-Jeff
 
Jeff,
I have done a lot of sailing--and a 36 degree angle of heel is more than I like to have, even when going to weather. However I would not be at all comfortable with less than 3" between my mast and the bridge (at 36 degrees)--I would want 5 feet to work with, and that would mean an angle of heel of 42 degrees. You are correct--not only the water bag (or dinghy full of water) could cause a drag, but also as you heel the boat over, the dynamics of hull, keel and rudder do change the steering. If it works out to 36 degrees, I would want at least 5 feet of clearance for wake, etc--and that would work out.

I have real world experience in this--having taken a boat with a 62.5 foot bast, plus 3 foot SS whip antenna on the top--up and down the Atlantic Coast ICW. It is a bit scary as the whip goes ting ting on the lowest point of the bridge.

It has been done, but not a great idea on a regular basis. I tabernacled a 65 foot mast to fit under a 20 foot bridge (Anaheim landing PCH bridge at Huntington Harbor) That allows regular access under low bridges, at a price.
 
1. (Christian Religious Writings / Bible) (often capital) Old Testament
a. the portable sanctuary in the form of a tent in which the ancient Israelites carried the Ark of the Covenant (Exodus 25-27)
b. the Jewish Temple regarded as the shrine of the divine presence
2. (Non-Christian Religions / Judaism) Judaism an English word for sukkah
3. (Christian Churches, other) a meeting place for worship used by Mormons or Nonconformists
4. (Christianity / Ecclesiastical Terms) a small ornamented cupboard or box used for the reserved sacrament of the Eucharist
5. (Christianity / Ecclesiastical Terms) the human body regarded as the temporary dwelling of the soul
6. (Christianity / Roman Catholic Church) Chiefly RC Church a canopied niche or recess forming the shrine of a statue
7. (Transport / Nautical Terms) Nautical a strong framework for holding the foot of a mast stepped on deck, allowing it to be swung down horizontally to pass under low bridges, etc.
Click to expand...

it mush be risky and require pray. and Hear I though it was just a singing group :note
 
Tom, this is a tabernacled mast.

145-06-Photo-for-web.jpg


Not easy on a big boat as the weight as it gets past the 45deg angle becomes very difficult to handle. Particularly if the boat is rocking at all.. :shock:

I had one on a 23' boat in Monterey, just used it for travel and storage, not for bridges..

Charlie
 
I have had several sail boats with tabernacled masts: Most were pivoted at the deck level, and were a simple hinge on the deck stepped mast and used the boom as a level arm. The 65 foot mast was on an ocean racing boat, so we had to have both a very sturdy locked system when the mast was up, but easy enough for one man to take the mast down when going in and out of the harbor. It involved pivoting the mast 7 feet above the deck with a 3" diameter pivot pin. The stub of the mast, was braced with an "A frame" aft (braced by a structure under the deck), and a 12,000 lb capacity Holmes tow truck winch with 3/8" cable on the cabin house in a teak box, provided the force to take the mast up and down, thru the fulcrum arm of the lower 7 feet of the mast off the cabin top. (There was a box section consisting of the front of the mast, which fit into the stub, and locked with another 2" SS pin driven into the base of the mast at deck level. There was a hydraulic pump to tension the back stay (and forestay--which was released, as well as the forward lowers, and there was a pivot point at the 7' level on the upper shrouds. )

Yes, Tom, there were prayers the first time we used the system (at the dock), and as Charlie pointed out that the boat had to be in calm water. The boat also had to be aligned with the wind fort and aft. When the mast was down, the boom rested on a crutch on the cabin top, and the mast on a crutch which fitted into a socket on the transom.

The whole procedure up or down, took about 3 minutes, and was done with the boat underway. It was done hundreds of times with no failures.

I am sure that the water ballast bags are far cheaper than the extensive modifications we made to the mast and boat.....and work find for an occasional trip under a bridge.
 
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