Quick question. Assume a 40 foot cruising cat flips in heavy weather offshore. The wind is 30-40 knots and waves are 2 meters same direction as the wind. The boat is 110 degrees and the mast is holding
The wind and waves will push the boat keel first or mast first?
Based on numerous capsizes to 90 degrees on Elementarry,
ELEMENTARRY – Harryproa http://harryproa.com/?p=1753I think the mast will act as a sea anchor and the boat will end up downwind. Not many cats (racing or cruising) will stay on their sides at 110 degrees for long before the float is destroyed or the rigging breaks. How do I know this?
38 years ago, I capsized a racing cat in the Atlantic. It inverted quickly enough that I hardly slid down the shroud I was clutching. The boat then lay side on to typical Force 5-6 waves. Each time one went past, the boat would move sideways, the sails would fill and the boat would accelerate up to a knot or so. The motion (and the temperature) were bad enough that we got in the liferaft (cheap rental, which did not auto inflate, nor have a double floor) which we tied to the stern. There is a picture from the aircraft that found us (only just, the hired EPIRB was rubbish as well) with the liferaft streaming astern of the boat at 90 degrees to the breeze. The motion in the liferaft was worse than on the boat, but warmer. Each wave would cause it to jerk and spin so I had to hold onto the painter and play it to minimise the motion. Not all bad, it stopped me thinking about sailing at 1.5 knots to America, how I was going to pay back the loans and the scorn I would (rightfully) get for joining the stupid enough to capsize club.
A cruiser would have needed more wind causing bigger waves to capsize, with bigger loads from the waves. The float or mast would not have had a chance.
I see what your saying but the ama is traditionally much lighter, shorter, and smaller which makes the boat unstable when inverting.
The model uses an ama much longer than the main hull to ensure stability.
Not real sure how this would work.
First, lets use sensible terms.
The lee hull is the long one, (or 2 short ones arranged fore and aft in the picture above and the model, which is atypical of harryproas and makes no difference to the righting) which has the rig, rudders and false floor in it, but nothing else. It is always to leeward.
The windward hull is the short one, closest to me in the video and has the crew, accommodation, and all the stuff usually on a boat. On a typical harry, it would be bigger than on the model.
The lee hull supports about 40% of the total weight, the windward hull about 60%.
The windward hull is shorter, has little effect on fore and aft stability when capsized as it is out of the water. The lee hull, when submerged has none either. Hence the need for a schooner rig.
It is not a traditional set up and will not work for a proa that is. Nor will it work for a cat or tri, unless the crew weight is an appreciable part of the total. ie a beach cat.
The model has a masthead float to compensate for the mast being set inboard. It does nothing after the lee hull starts to sink. It would not be required on other harryproas as the sealed, large diameter masts are in the lee hull so they don't capsize beyond 90 degrees.
Hope this makes it clearer. If not, please say so.
As far as winching floating objects - how do you do that in conditions that are so bad that the boat capsized? At the very least one will normally have to wait until the weather improves, which brings problems of its own. I'm still not aware of any of the self righting systems that have really been proven to work after an accidental high-wind capsize.
Agreed. As did Harvey, who owned Orion. It was only meant to work in flat water and daylight. As such it was a fun project, but pretty hopeless for real life so he removed the float.
Derek Kelsall built a cat with a tricky arrangement of ballast tanks which could be flooded and drained so the boat would right stern over bow from inverted. There is a video somewhere of proving it on a lake. There is nothing obvious in the system, (the boat, rig and crew are a different story) that would stop it working in big seas. Walter Greene built a 50' cat with a sinker hull (no core) which in theory would flood and allow righting. Not sure if he ever used it in anger. Neither of these were self righting as both needed crew input. There is a proa with a small ballast keel being built in Italy. Should be self righting. In theory, it should not capsize in flat water.
