Dave and I have been puzzling over this all day (among other things): How much ballast should QUIDNON carry? Its beam and hard chines will make it very stiff for very little ballast, but how much is enough, and under what conditions?
To answer that question, let's ask another one: Take your typical cruising sailboat if you take it out into a near gale, a fresh gale, a whole gale, or a strong gale, corresponding to 7, 8, 9 and 10 on the Beaufort scale (we won't do this exercise in a whole storm because that would be completely stupid in any boat). What happens if you then put up all the sails (in this case, 1000 ft of canvas), sheet them in as tight as you can, and... turn the boat sideways to the wind?
Answer: instant knock-down. Right?
Wrong! I did this with HOGFISH in a near gale, and what it did was wallow at a 45ยบ angle, gently drifting to leeward. Her builder, Chris Morejohn, said he did this same exercise on purpose during her sea trials, with his friend who is a naval architect, in a gale, and found that doing so had a similar effect. He said that she is impossible to capsize, and I believe him.
I want QUIDNON to behave similarly well, so I did some math. Here is a little table I put together:
The thing being calculated is the amount of ballast needed to achieve this effect under various conditions. Now, 40,000 lb of ballast is borderline reasonable. Above that we get into the somewhat ridiculous territory; the boat would still float fine, but would be fully loaded with ballast in order to make it safe for a completely incompetent, borderline suicidal skipper. And that just isn't me.
Keeping in mind that 1000 sq. ft of canvas is quite a lot, and that this exercise is about as extreme as I can imagine (don't try this with your boat, please!) I am tempted to just dial in the ballast at around 20,000 lbs and leave it at that. After all, the Junk rig is so easy to reef when the wind picks up.
To answer that question, let's ask another one: Take your typical cruising sailboat if you take it out into a near gale, a fresh gale, a whole gale, or a strong gale, corresponding to 7, 8, 9 and 10 on the Beaufort scale (we won't do this exercise in a whole storm because that would be completely stupid in any boat). What happens if you then put up all the sails (in this case, 1000 ft of canvas), sheet them in as tight as you can, and... turn the boat sideways to the wind?
Answer: instant knock-down. Right?
Wrong! I did this with HOGFISH in a near gale, and what it did was wallow at a 45ยบ angle, gently drifting to leeward. Her builder, Chris Morejohn, said he did this same exercise on purpose during her sea trials, with his friend who is a naval architect, in a gale, and found that doing so had a similar effect. He said that she is impossible to capsize, and I believe him.
I want QUIDNON to behave similarly well, so I did some math. Here is a little table I put together:
Keeping in mind that 1000 sq. ft of canvas is quite a lot, and that this exercise is about as extreme as I can imagine (don't try this with your boat, please!) I am tempted to just dial in the ballast at around 20,000 lbs and leave it at that. After all, the Junk rig is so easy to reef when the wind picks up.
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