We have gust of high thirties forecast tomorrow. Both boats have mast floats, and have and have a single tie down rope to the center of the aft cross bar. At what wind strength do boats start getting knocked over?

I may head there to drop masts, or add a second tie down under the mast. A buried timber under a few feet of sand, and some goid rope.

Thanks.

--
John

Nacra 5.0
CT
--

what kind of tie down?
what kind of soil?

mast floats add windage
so do jibs, i would take mine off

we have seen cats flipping on the beach (actually nose on the trailer, transoms in the sand) around 30knots
i would think flat on the ground is safer but if/when wind gets under the tramp ... it becomes a sail so unure if higher on a trailer may even be better

if tied to a trailer i would chock the wheels - i've had my boat/trailer pushed down the beach in a gust a few times

we took our masts down nacra 570 & Dart 18. Gordon put away/called it a season, his new Astus 23 trimaran to avoid himicane Jose,`lost a Dart 18 to Irma in Ft Lauderdale last week! Our cats are moored on mushrooms on Great South Bay Long Island.. we used to keep cats on a beach on the Atlantic side of Fire Island and than on bay side. We used screw downs approximate length 48 inches 4 per cat in the sand. We also took a 2by4 and screwed cross pieces of 18 inch 2by4 to bottom and dug down 4 feet and buried them (in wet sand that deep ) screwed in a hook atop 2 by 4 and tied down cats to rope thru hooks all 4 sides. worked great we always tied down after every day of sailing, when winds exceed 25mph & get under tramp cats can flip. I believe i lost my nacra5.2(see my photo album for pictures)during hurricane Sandy to rope tie downs because with tidal surge cat was literally tied down and then submerged for days and broke up, so tie downs not good for flood conditions move cats to higher elevation first i lost a hobie 16 that floated out into the atlantic on beach wheels to early 70s n'or easter

I'm assuming your question refers to how much wind does it take to flip a cat under bare poles. With sails up would obviously take much less wind. I would think with the boat sitting flat on the beach you would need at least mid-30 knot winds for the average cat and there probably isn't much real danger until the wind starts going over 40. A light weight boat like an A-cat or F-16 would be significantly less however.

To be safe, definitely anchor the boat either at the front crossbar or with one anchor on either side connected to the trap wires. The recommendation to take down a furled jib is also a good one. If it starts to unfurl accidentally, it will get shredded.

sm

Quote

The recommendation to take down a furled jib is also a good one. If it starts to unfurl accidentally, it will get shredded.

even if it doesn't open. it will add a LOT of windage .. .that could create a failure to your forestay attachment somewhere ... or just work/worm beam bolts and stay fittings with hours and hours of strong gusts

I would also add that having a snorkel over the jib is not a guarantee that the jib won't unfurl. Several years ago, I had my boat stored on the beach with the jib furled and a snorkel over top thinking it would be fine like that. We had a strong Nor'Easter come through and it ended up blowing apart the zipper on the snorkel and then the jib partially unfurled and got very beat up from the flogging. Lesson learned, always drop the sails when strong weather is forecasted.

sm