Thought ya might enjoy comparing our lil yachts against others....they more than hold their own in 'capsize screening and motion comfort' ratios. Have fun comparing www.image-ination.com/sailcalc.html I found it interesting that our lil Ariel has better #'s in both departments than my former beneteau 331 !!!
Last edited by frank durant; 07-27-2005 at 05:20 PM.
Is heartbreaking what has happened to the S/V Wingnuts in the Chicago to Mackinac race yesterday and today. If you haven't heard, the 35 foot vessel capsized in 60 to 70 knot winds and 6 foot seas off of Charlevois Michigan. Six were rescued, but two drowned. I'm posting the first pictures of the overturned vessel, but I can't make out very much about the design to understand what might have gone wrong and why she didn't right herself after the knockdown. The keel seems to be in place, and with the seas, I'd think that she'd roll back over. Anyone heard what the design is or have thoughts after looking at these first pictures?
Looking at the displacement number, I'm not surprised the boat could not come back after turning turtle, unless there's a mistake in that number. This boat is half the weight of an Ariel! I don't think it had a bulb.
I think it's just like a catamaran really, counting on stability from it's broad beam. Once it flips, there's no coming back!
That thing did have a bulb on the end of that keel blade - remains are there - that cream colored stuff looks like foam.
Also, the 35 footer had a beam of 8.5', with foldout "deck wings" that increased the 'beam' to 14'.
I don't know for sure, Ebb. The picture isn't very clear, and it appears the Coast Guard attached some hazard beacon and warning signals on the boat. Why would a bulb have foam? I'd think they would put the densest, heaviest material at the end of that blade. If the boat is only #2800 pound, even if there was a bulb, it would have minimal righting moment. And they carried a crew of 8 on it! That might be good when you can use them for rail meat on the wings, but at night they probably crammed in the cabin. Terrible boat to be in tough conditions, they seem more like hobie cats, and less a displacement boat.
Stephan, You're right!
Bulb and sheel shapes on the bottom of a keel have been shown
to actually slow a boat down, even tho you get more weight lower for your buck.
So this all out speedster probably wouldn't have a shape on the bottom.
Your forensics show that bodies rather than lead was used to race that thing.
However, if it is a Kiwi35 you can bring up drawings that show its keel has a torpedo
shape added to the bottom of the keel.
Can see the sails down in the water in one foto. Do you think they might have created enough drag to keep the hull from righting itself?
As you point out, it's too light a displacement to have ANY lead anywhere!
Too bad lives were lost. There is no excuse for that.
But where would SPORT be
without extremes and danger?
In those winds and seas any boat, even an Ariel, would be in trouble.
A Kiwi35 should not be out in anything more that 25knots and a light chop.
Quite recently one of those America'sCup sleighs hit a bumpy wave on SFBay and nosed right in.
And around the same time a small seaplane did the same before a bunch of diners in a restaurant on the Sausalito waterfront. Captured on video, the plane is taking off at speed,
hits a bump, noses up - and immediately dives in!
Lots of fun!
Here's a picture of Wingnuts in better days. Sure looks like the Kiwi 35 that Stephan posted the link earlier. I read that the crew had doused the mainsail and put on harnesses prior to the storm hitting, but that they were capsized when a 75 mph gust hit. If that design is as light as in the specs listed in the article Stephan posted, and if the "bulb" was just a smaller ballast type (this design can be trailored), it doesn't surprise me that a gust of that magnitude could have lifted up the side of the boat when it hit under one of those wings on either side which flare out at the deck and flipped her over. Wind resistance would be awesome. Kind of like trying to carry a sheet of plywood to the truck outside of Home Depot on a very windy day.......
This boat would really have to move tons of water to right itself when capsized with those hull wings and sails up. Looks to be a very stable platform when inverted. Very sad indeed, 25% of the crew lost.
Is there an answer?
Some thought has to be given to the worst case.
That hull has nothing to hang on to when upside down. No place to even plant a foot.
The boat survives, as often the case, some people don't.
Like you say when those deck wings caught that gust who knows what the boat actually did,
WHAT ARE THOSE ROCKET WINGS SUPPOSED TO DO ANYWAY? Lift the boat going to windward? Increase the aeroline length, instead of the waterline?
Guys could have been knocked unconscious, couldn't fend for themselves,
were they wearing safety gear that automatically turns you face up? There seems to be very little deck gear/rope/life lines they could get tangled in.
There must have been some indication that this type of boat has the propensity to catch wind by its hull shape.
There has to be a record of wind and tank testing.
When the hull is leaning on a beat, does the leeward wing dig into the water?
Does the windward wing catch the wind when it's standing? It certainly is a deliberate tube like cove shape.
Maybe the rudder broke. Were they in control? They must have broached, they must have had 5 seconds to get ready.
Maybe the wings outer edge should terminate in a hollow torpedo shape for bouyancy. Make it harder for the boat to be driven under. Like a trimaran ama.
Maybe there should be openings in the wide deck to let wind through - and water.
And provide footing for dumped crew.
My assumption is simply moves the meat on the rail further outward to gain a weight multiplying advantage. It appears a hard chined hull designed to sail pretty flat, needing the crew on the rail. Any Alberg design couldn't remain inverted like this even if the mast stuck in the mud!!
www.image-ination.com/sailcalc.html I found it interesting that our lil Ariel has better #'s in both departments than my former beneteau 331 !!!
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