I've thought about this to help me get under the bridges at Fremantle.
I calculated I'd need to heel over about 45 degrees, but then I'd have the problem that the bridge span may not be wide enough.
Select to expand quoteRamona said..fishmonkey said..
trigonometry?
Sextant.
i would definitely like to learn how to use a sextant.
however to fit under the bridge using this audacious method simply requires that the rope plus the length of the weighted bags is shorter than the bridge clearance. then you just need to add enough ballast to the bags so that they are touching the water.
if the span between the pylons was limited some basic trigonometry using the mast height above water would tell you if you'd fit horizontally...
It is possible to get stuck under a bridge. On a Manitou, getting closer and closer to the St Huberts Island bridge on Central Coast our for'ard hand called "she'll fit" She'll fit". We had the boat heeled over too. Then for'ard jumps up in a panic calls out "It wont fit" GO BAAAACK!!!! Too late. We were running with a decent current as well.
The mast hit with a nasty scraping sound. The boat then twisted around broad side onto the current and wedged herself hard against a pylon of the bridge. Bits from the top of the mast sprinkled onto the deck.
A crowd of locals showed up. Many saying "you guys are stuck". Call the coast patrol. etc. Our skipper (big scary ex bouncer) said to them $***%& dont you think we know that shut the ^*(^( up. They shut up because at this point he could easily step off the boat onto the shore and they could see that.
We got unstuck by 30 minutes of pushing and pulling the boat. Left a white zig zag scratch in the concrete under the bridge from one side to the other showing where the masthead had been. The Manitou had a few dings on the hull but not too bad, and the wind vane and anchor light were removed from the top of the mast. The original plan was to sail to the Newport Arms for lunch but because the weather was bad decided to circumnavigate St Huberts Island. Should have stuck to the lunch!
