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MazeRat7 09-22-2009 12:14 AM

Knock Down Drills?
Excuse my paranoia, but last weekend on a perfectly tame day I watched two larger boats (a Catalina 28 and a Benateau 30-something) almost put their spreaders in the water when we were hit with out-flow from a passing thunderstorm. I saw it happening and had barely enough time to douse the genny and point up.... I still cleaned the windows and took on water.

Granted my little cat is really tender, but still I would like to avoid a salvage operation that cost more than my boat.

In a previous thread I posted this link about The Science of ballast and heeling for a Catalina 22 and as you can see from the analysis, anything more than about 70lbs of weight on the midpoint of my mast will keep the boat from righting after a 90 degree heel.

70lbs is not much margin when you consider water in a sail, a crew member hanging on, etc.

So I guess my question is, how do I vet my "knock down" plan. I know its going to happen someday, though I try my best to keep her on her feet. Its not like a MOB or Hove to drill... its more a thought experiment or plan. What things would/have you folks done when the mast is in the water and there is not enough counter torque to right the boat?


Stillraining 09-22-2009 01:33 AM

I have never laid a big boat over but I have laid 21 &< over on ocation...

First boat was a mac21..she laid on her side for a good 30 seconds before one of the crew grabed the keel and pulled himself up on it at which time she righted herself with force and with a full mainsail of water and me standing in the sail to boot..I would not worrie about the righting so much..I would worrie about the down flooding.

We almost lost a buckaneer 20 due to that.

saildork 09-22-2009 09:01 AM

Interesting post, MazeRat.

Great link too. Having filled the cockpit a couple times on very windy days,:eek: I can tell you that the first thing to do is to keep your hatchboards in place and find a way to make the cockpit drain faster. I invested in the kit from Catalina Direct that allows you to drill holes in the transom to mount their thru-transom scuppers. They work great, draining the cockpit a whole lot faster than the little factory-mounted drains in the forward end of the cockpit. The instructions in the kit are straightforward, and the tools they send you almost assure a professional result. Mine look great and don't leak into the bilge.:)

Something else I've toyed with is finding a way to fill mast with styrofoam popcorn, or otherwise making it somewhat water-tight by somehow sealing the ends of the mast to limit how fast water can get into and fill the mast. This wouldn't make the mast bouyant enough to keep the boat from turning turtle, but it would slow the ingress of approximately 2.7 cubic feet of water entering the mast. This might at least slow the capsize process long enough for the skipper to regain his wits, and to climb onto the keel to re-right the boat before it's too late. Has anyone else done this?

C22 'Stargazer'

Faster 09-22-2009 09:42 AM

I seem to remember someone making an automatic inflatable bag for the mastheads of boats that won't self-right.. much like the inflatable collars many of us wear these days.

Put the mast in the water, the bag deploys and prevents turtleing.

t22cayuga 09-22-2009 09:58 AM

I think that was Donald Crowhurst. Not sure you'd want to follow his example...

Sailormon6 09-22-2009 10:19 AM

In a knockdown, the most important thing is to keep water out of the boat. If it fills, it'll sink. When foul weather is expected, the hatchboards should be in place, and all opening hatches should be secured. Also, people often forget to secure the cockpit hatch lids, and, if the lids fly open in a knockdown and the locker fills, it can quickly sink a boat. A padlock or other device should be kept in the hasp at all times.

tommays 09-22-2009 10:24 AM

The only thing you do is keep things like hatches doged closed(fasten them closed) so they cant allow large amounts of water in

On the bigger boat when we get into dicy conditions we use a different lower hatch board that locks into place which keeps water out of the cabin if the cockpit floods

In are last distance race on the J24 it got crazy near the finish and many bigger boats that had failed to reef early got into far more trouble then we did by carrying less sail and being aware of the changing weather

PCP777 09-22-2009 11:47 AM

Good idea for a thread. Some real good tips here. Check out from the top of page 151 on the BFS thread for some interesting pics of a boat that got pretty close to this position in last Wednesday's race. The good news is they made it.

Faster 09-22-2009 11:52 AM


Originally Posted by t22cayuga (Post 525006)
I think that was Donald Crowhurst. Not sure you'd want to follow his example...

Yeah... but this was more recent and with today's auto inflating technology it could actually work.

midnightsailor 09-22-2009 12:36 PM

One thing I didn't see mentioned was to place some flotation like a life jacket or throwable flotation device under the mast head should the boat go over and lay on its side. This is standard for small boats like a Blue jay, etc. when going about righting them. THis goes along with getting weight on the keel which was already mentioned. When I first learned to sail way back in 1963, it was on a blue jay and was one of the first things we were tought. I believe on your CAT 22 this might be helpful. Of course, your going to have to getwet, but from what you describe looks like that may be a given anyway, Rick

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