Light wind trim

   Having just come back from Grafham.

On the light wind day I noticed some crews lying along the leeward hull forward of the beam, while some others lie along the windward hull. Which is fastest? and why?

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Wee Man Send Private Message Find Member's Posts Far too distracted from work Joined: 24 Aug 06 Location: United Kingdom Online Status: Offline Posts: 214	Post Options Post Reply Quote Wee Man Report Post Quote Reply Topic: Light wind trim Posted: 18 Oct 10 at 1:08pm
	Having just come back from Grafham. On the light wind day I noticed some crews lying along the leeward hull forward of the beam, while some others lie along the windward hull. Which is fastest? and why?

mattmd Send Private Message Find Member's Posts Posting king Joined: 23 Mar 09 Location: United Kingdom Online Status: Offline Posts: 151	Post Options Post Reply Quote mattmd Report Post Quote Reply Posted: 18 Oct 10 at 5:11pm
	When I sailed F18, On lightwind days id crew, by sitting on the leeward side, this is because it would lift the windward hull and reduce wetted surface area, and consiquently go faster. But just getting your weight forward helps speed as it stop the transom from digging in. But I personally would sit on the leeward side, however be carefully if your sailing somewhere gusty, be ready to run over the other side if it heels massively, gain speed from gusts do not pinch. Hope this helps
	Matt MD Contender GBR-620

Black no sugar Send Private Message Find Member's Posts Visit Member's Homepage Really should get out more Joined: 04 Dec 04 Location: Somewhere between Brighton and Lancing Online Status: Offline Posts: 3941	Post Options Post Reply Quote Black no sugar Report Post Quote Reply Posted: 18 Oct 10 at 7:41pm
	It's only a Topper tale so feel free to ignore. During the summer, we were two Toppers side by side on a broad reach / run in light wind. We were both on a starboard tack with me on the outside, trying to get faster. We sailed most of that leg at the same speed. Thinking I'd had enough, I assumed the monkey position (holding on to the daggerboard, leaning to starboard, as good instructors teach) and I was surprised to see how much quicker the boat went. I pulled away from the other boat really quickly, considering the wind strength. In your question, you don't mention the point of sail so this answer is probably... pointless! Edited by Black no sugar - 18 Oct 10 at 7:42pm
	Lancing SC

zailor Send Private Message Find Member's Posts Visit Member's Homepage Far too distracted from work Joined: 10 May 09 Location: Penparc Online Status: Offline Posts: 249	Post Options Post Reply Quote zailor Report Post Quote Reply Posted: 18 Oct 10 at 8:09pm
	so was that windward or leeward heel?^

Wee Man Send Private Message Find Member's Posts Far too distracted from work Joined: 24 Aug 06 Location: United Kingdom Online Status: Offline Posts: 214	Post Options Post Reply Quote Wee Man Report Post Quote Reply Posted: 18 Oct 10 at 8:52pm
	Mainly noticed the different style upwind, I was wondering if it has anything to do with the different bows on the newer boats (Wild Cat, Edge, Infusion).

kfz Send Private Message Find Member's Posts Groupie Joined: 02 Nov 10 Location: UK Online Status: Offline Posts: 96	Post Options Post Reply Quote kfz Report Post Quote Reply Posted: 01 Dec 10 at 9:35am
	Depends on how light the wind is. Very very light winds where your struggling to fill the main I tend to get the crew on the leeward side and get the boat healing just a little, Its holds the boom out and helps the sail get some sort of shape. Vital theres virtually no kicker, though I have experimented with using a little outhaul lately. Once you have enough wind to hold the main shape then whatever side holds the boat dead level. Let the outhaul off and get the slack out the kicker. Not sure if this is right or not.
	GP14 Fleet Captain Liverpool Sailing Club Liverpool SC

alstorer Send Private Message Find Member's Posts Really should get out more Joined: 02 Aug 07 Location: Cambridge Online Status: Offline Posts: 2899	Post Options Post Reply Quote alstorer Report Post Quote Reply Posted: 01 Dec 10 at 9:37am
	kfz- this is the multihull section!
	-_ Al

kfz Send Private Message Find Member's Posts Groupie Joined: 02 Nov 10 Location: UK Online Status: Offline Posts: 96	Post Options Post Reply Quote kfz Report Post Quote Reply Posted: 01 Dec 10 at 10:02am
	oops
	GP14 Fleet Captain Liverpool Sailing Club Liverpool SC

snowleopard Send Private Message Find Member's Posts Visit Member's Homepage Groupie Joined: 02 Oct 17 Location: Cornwall Online Status: Offline Posts: 66	Post Options Post Reply Quote snowleopard Report Post Quote Reply Posted: 15 Mar 18 at 1:59pm
	Regardless of the number of hulls, at very low speeds, skin friction is more significant than waterline length or hull form so altering the trim of the boat to reduce wetted surface does help speed. In cats, there is less opportunity than monos but moving forward to lift the stern clear of the water does help. At what speed you stop doing that is a matter for experimentation. I remember competitive Laser sailors sitting forward of the mast to lift 3 ft or more of the stern clear of the water in ghosting conditions.
	One hull good, two hulls better.