On Wed, 23 Apr 2008 10:29:26 -0400, Marc <noone@[EMAIL PROTECTED]
> wrote:
>
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>Last November. I brought my F36 to a DIY yard for winter storage and
>bottom work. The yards benefits were off set by distance, tolls and
>a 55' fixed bridge. But, with a 6' tide, still a net plus.
>
>Come March, I discover that the DOT has begun re-decking the bridge
>and has hung a safety scaffold below. Checking the Notice to Mariners
>(belatedly) I find that the public notice was given and permits were
>issued for a five foot reduction in bridge clearance.
>
>I did not want to remove the mast for a number of reasons including:
>inexperience of the yard in handling a Freedom mast, not wanting to
>disturb a perfect, non-leaking seal, not wanting to carry the mast as
>deck cargo to another yard, and the cost of removal and re-stepping.
>
>My best measurements showed a 55' mast hgt. including anchor light,
>with all instrumentation removed except for the VHF radio antenna.
>Hitting the optimum tide at my target launch date would give me 5.8'
>below Mean High Water and a calculated clearance of 55.8'.
>Accordingly, I figured a 15 degree heel would see me safely under the
>bridge.
>
>Having made the decision to heel the boat, the next considerations
>were how to load, how much to load, what to load and how to rig the
>boat. I wanted to deck load as much as possible and keep as much
>strain off the mast as I could, while at the same time preparing the
>mast for as much strain as needed. I opted not to use the main halyard
>but instead installed a choker around the mast just above the fore
>stay attachment point.
>
>Using the blocks from my vang and the second reef line I created a 3
>part tackle by attaching a block with becket to the choker and a block
>to the boom. The free end of the reef line was then rove from the out
>haul at the end of the boom up to the choker block, back down to the
>boom block and back up to the becket on the choker block. Now I had a
>crane with control lines that led through my deck organizer, clutches
>and to my winches; Up and Down by the reef line, In and Out by the
>main sheet and traveler. A preventer to a snatch block on the bow
>completed the rig.
>
>I began loading by filling the 60 gal. potable water tank below and
>la****ng a 55 gal drum to the deck and filling that. It barely made a
>dent, 3 degrees at best. I then decided on sand bags. At $1.75 for
>each 50 lb. bag, they were cheap and easily jettisoned. After loading
>1200 lbs at the toe rail, I still had only 10 degrees of heel.
>
>On to plan B. I bought a 1 cubic yard bulk load polypropylene bag with
>a 3300 lb rating for $40.00 , attached it to the boom and began
>loading the individual sand bags into it. Ultimately, it took 900 lbs.
>on the boom and 300 lbs. on the deck to heel the F36 to 15 degrees.
>
>Ultimately, The boat made it under the bridge, but barely. For all the
>figuring in the world and all the careful prep work, my VHF antenna
>bent in half acting as curb feeler on the underside of the bridge. I
>knew the height of my mast from an empirical measurement. I knew the
>degree of heel needed for a worst case scenario. I had an accurate
>method of measuring the heel. The only variable was the tide. I had a
>tide prediction for the exact point I had to pass, including moon
>phase. We got to the bridge exactly at the time predicted. All
>indicators were good to go, slack water, calm seas, tidal indicator on
>the bridge, known visible sand bar exposure at low tide etc. and still
>we just made it. It appears that the tidal range prediction was not
>accurate.
>
>.
That's why they call them "predictions". :')
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