mad moth idea

   It's not the rig being angled to windward but the fact that the boat, when foiling, pivots around the bottom of the foils (the roll centre?) so leaning to windward moves the CoG of the boat plus helm further to windward of the 'roll centre', the righting moment works vertically downward (gravity) so the more you heel the greater righting moment you have. The opposite applies too as anybody who has allowed a Laser to heel too far and the point of no return comes when the sailor is above the centre of buoyancy (which in the case of displacement sailing is effectively the equivalent of the roll centre?)

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Sam.Spoons Send Private Message Find Member's Posts Really should get out more Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3400	Post Options Post Reply Quote Sam.Spoons Report Post Quote Reply Topic: mad moth idea Posted: 18 Apr 20 at 6:09pm
	It's not the rig being angled to windward but the fact that the boat, when foiling, pivots around the bottom of the foils (the roll centre?) so leaning to windward moves the CoG of the boat plus helm further to windward of the 'roll centre', the righting moment works vertically downward (gravity) so the more you heel the greater righting moment you have. The opposite applies too as anybody who has allowed a Laser to heel too far and the point of no return comes when the sailor is above the centre of buoyancy (which in the case of displacement sailing is effectively the equivalent of the roll centre?)
	Spice 346 "Flat Broke" Blaze 671 "supersonic soap dish"

giraffe Send Private Message Find Member's Posts Posting king Joined: 10 May 07 Online Status: Offline Posts: 148	Post Options Post Reply Quote giraffe Report Post Quote Reply Posted: 18 Apr 20 at 5:57pm
	the rig canted to windward gives more righting moment too - and I believe this aspect is considered to be highly beneficial - but I may be out of touch

ian.r.mcdonald Send Private Message Find Member's Posts Far too distracted from work Joined: 24 Feb 06 Location: United Kingdom Online Status: Offline Posts: 440	Post Options Post Reply Quote ian.r.mcdonald Report Post Quote Reply Posted: 18 Apr 20 at 5:42pm
	Being able to cant the rig radically to windward is essential- a shorter fall for me as I tip it in (yet again)

Sam.Spoons Send Private Message Find Member's Posts Really should get out more Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3400	Post Options Post Reply Quote Sam.Spoons Report Post Quote Reply Posted: 18 Apr 20 at 12:18pm
	With a fixed rig it's basically down to the righting moment balancing the heeling moment like any dinghy. It would probably be possible to sail the upright with the helm out on the wing but by heeling to windward you gain considerably more righting moment as the Centre of Lift/Buoyancy is further to leeward of the 'ballast'. Getting the mast vertical would reduce the lift component from the rig but will increase the drive component but I'd guess only a little. I think canting the hull with the rig would slightly reduce the righting moment so may not have any benefit. Edited by Sam.Spoons - 18 Apr 20 at 12:24pm
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423zero Send Private Message Find Member's Posts Really should get out more Joined: 08 Jan 15 Location: United Kingdom Online Status: Offline Posts: 3420	Post Options Post Reply Quote 423zero Report Post Quote Reply Posted: 18 Apr 20 at 11:33am
	Presumably the lift from foils while boat is heeled to windward also stops boat making too much leeway ?
	Robert

423zero Send Private Message Find Member's Posts Really should get out more Joined: 08 Jan 15 Location: United Kingdom Online Status: Offline Posts: 3420	Post Options Post Reply Quote 423zero Report Post Quote Reply Posted: 18 Apr 20 at 11:08am
	They all appear to heel to windward in this short video. https://www.youtube.com/watch?v=WEj_xNcZXF0 Edited by 423zero - 18 Apr 20 at 11:08am
	Robert

GarethT Send Private Message Find Member's Posts Really should get out more Joined: 21 Apr 07 Online Status: Offline Posts: 714	Post Options Post Reply Quote GarethT Report Post Quote Reply Posted: 18 Apr 20 at 10:02am
	I'd always assumed it was so the foil was lifting upwind as well as up out of the water.

Rupert Send Private Message Find Member's Posts Really should get out more Joined: 11 Aug 04 Location: Whitefriars sc Online Status: Offline Posts: 8956	Post Options Post Reply Quote Rupert Report Post Quote Reply Posted: 18 Apr 20 at 9:32am
	Isn't one of the ideas on windward heel that when you catch a gust, the mast goes upright, rather than to leeward, which would cause you to crash and burn. My poor understanding was that it was the combination of rig and foil angles that would cause the crash, but I'm clutching at ideas which are slightly beyond me.
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Riv Send Private Message Find Member's Posts Far too distracted from work Joined: 23 Nov 13 Location: South Devon Online Status: Offline Posts: 353	Post Options Post Reply Quote Riv Report Post Quote Reply Posted: 18 Apr 20 at 9:17am
	Parasitic drag on a Moth must be large. So far I've not seen any effective way of streamlining the sailor. So in comparison the complexity and weight of a canting rig may not give as much advantage as extra research into drag reduction. On the other hand rig canting ideas can be pursued more easily at home.
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The Moo Send Private Message Find Member's Posts Really should get out more Joined: 01 Jun 06 Online Status: Offline Posts: 809	Post Options Post Reply Quote The Moo Report Post Quote Reply Posted: 18 Apr 20 at 8:29am
	National 12 3489 Radical Edward started out life with a canting rig in the 2000s. It was the brain child of Mike Cooke of Aardvark fame who went on to do things in the Int Moth class