So, the asymmetrical vs the symmetrical discussion has been going on forever. So, I thought I'd add a new wrinkle (pun intended). My boat has dramatically swept back spreaders (H34) so the main gets against the spreaders when sailing much down of a beam reach. I understand that a symmetrical spinnaker allows a deeper downwind run but what if your main is draped over the rigging at that point? Have you lost any advantage to having a symmetrical spinnaker? Might you just as well go with the asym and steer a bit higher? Anyone with experience with this?
Spinnaker type for boat with swept back spreaders
- Thread starter markwbird
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I had that problem on the Venture 22, but if you're deep downwind (like wing-wing) then the main is on the spreaders - that's Just The Way It Is. If you like you can oversheet the main til it's off the spreaders and I doubt you'd see much difference in boat speed unless you're racing. (although it would be hard to sail By The Lee like that)
druid
druid
Yes. I would say that with the B&R rig you are better off with the asymmetrical, sailing higher angles and jibing your way down wind.
Even with a symmetrical there is a phenomenon known as the downwind cliff - if I remember my North U. course. It refers to the fact that polars for most racer/cruisers show a significant drop off in speed below an angle of 120 degrees or so. So the Rx is to sail above that angle and the increase in speed will make up the distance. Having said that, I believe it applies to Windward/Leeward courses primarily. In "Regatta" type races, which tend to use natural landmarks or government buoys for marks, you sail on a direct course from mark to mark and will not make up the extra distance sailed jibing downwind.
BTW, it never bothered me that much to have the main rest on the spreaders some.
Even with a symmetrical there is a phenomenon known as the downwind cliff - if I remember my North U. course. It refers to the fact that polars for most racer/cruisers show a significant drop off in speed below an angle of 120 degrees or so. So the Rx is to sail above that angle and the increase in speed will make up the distance. Having said that, I believe it applies to Windward/Leeward courses primarily. In "Regatta" type races, which tend to use natural landmarks or government buoys for marks, you sail on a direct course from mark to mark and will not make up the extra distance sailed jibing downwind.
BTW, it never bothered me that much to have the main rest on the spreaders some.
Actually backwards. 'Off the cliff' or 'down the shaft' refers to the fact that above a certain wind speed, its often best to point the boats almost DDW at the mark. Below 12-14 knots or so, a hotter gibe angle for best VMG speed is the ticket. Depending on a boat's polars, you'll sail 140-150 degrees. But with more wind, down the shaft! Aim at the mark!
You can see it here of the First 260 polars. Below 14 knots we are sailing wider for best VMG speed (ticks on the curve). But from 12-20, down the shaft.
But fun awaits for us at about 20knts; the First 260 planes and you heat back up to take advantage of that. On boats that don't plane you stay pointed at the mark.
You may be right about that Gunni. My understanding is that the H34 is pretty fast downwind which tends to add control. We will see. Sailing on a broad reach in heavy air is just as you describe. This is mainly due to the boat being way out of balance. A reefed main fixes it.
First of all, it is not advisable to fly a spinnaker with no mainsail (as someone suggested) unless the winds are pretty mild. Ever raised a kite in heavy air before hoisting the main in heavy air? You'll be in for a surprise and perhaps some rope burn. And the real question might be, despite the B&R rig with swept back spreaders, which spinnaker would you prefer depending on whether you are cruising or racing, lots of crew, or short handed? Because swept back spreaders inhibit deep dead down wind sailing, even without a spinnaker, as you will be more quickly be sailing on the lee because the mainsail cannot be let out as far as a boat with normal spreaders, the asymmetrical spinnaker might make more sense so that you can gybe downwind. Since a Hunter 34 is not usually considered a racing machine, the cruising A-kite might just be the best choice and if you can add a retractable sprit, that is even better. When you look at one design boats with a sprit for an asymmetrical spinnaker, the purpose of the sprit is to get the spinnaker out away from the mainsail so it doesn't block the wind. But, keep in mind, when raising the sail, the main does help keep control while the spinnaker sail is hoisted, otherwise, once raised and the wind fills the sail, you will experience a huge "whoomp" as the sail fills instantaneously and either broaches the boat because the crew and helms person isn't ready, not to mention the trimmer losing copious amounts of flesh as the line screams out through the blocks.
Perhaps the best reason why a spin sock is preferable to a spin furler - you can carefully control the set, in and out. And stuff the entire rig in a bag for compact stowage...
But for short-handed cruisers who needs the hassle of kite in a fresh breeze, just put the thing away, roll out the Genoa, and grab a sandwich.
But for short-handed cruisers who needs the hassle of kite in a fresh breeze, just put the thing away, roll out the Genoa, and grab a sandwich.
I probably should have mentioned that this is for racing. The question is all about performance. I do not use the spinny when cruising. I would much rather grab a sandwich.
That makes it easy. Spreader patches. Get some for your mainsail. Then go with a symmetrical, and sail to VMG angles.
Go up in a chair and check your spreader tips. Make sure they are perfectly smooth, and cannot catch the sail. Line up the patch so it centers on the spreader when the sail (vang!) are in downwind position. Don't worry about the sail pressing against the spreader. It can handle that. And so can the sail, unless it is WAY out (bad anyway) or relentlessly sawing against the tip.
Wind. 1992. For all of it's over-the-topness, actually not a bad movie, in particular if you like sailboat racing. FFC produced it. Loved when Jennifer Gray says 'You've got to put up the Whomper'. Anyone with a big-ass kite loves that line.
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If a boat does not plane, more breeze adds more apparent wind as the boat maxes out on boat speed. Then any 34 footer is is going as fast as it can. This inevitably makes the boat LESS stable. Things like hull form, rudder design, VCG, etc help but at the end of the day you gotta deal with the pressure before you wipe out.