Recently reading North Sails
U-Trim I found the comment on pg 146 that a symmetrical spinnaker
is not an optimal shape specifically on the luff and leach length and that this compromise is due to the fact that they must be interchangeable. The commentary then goes onto talk about rigging
an asymmetrical with a normal pole. It's also described nicely here:
Quantum Sail Design Group AY Promotion
I normally run an asymmetrical on a bow sprit so my question to the forum is if this described method would still be optimal to achieve a better VMG closer to a run. Normally the use of an asymmetrical on a bowsprit
forces one to reach down the course more so than one would with a symmetrical. To clarify further, the described method would enable one to move the tack and luff further to the windward side out of the shadow of the main, as you can with a symmetrical. My guess is this would be a great trick to improve VMG but there may be an issue with the resulting sail shape. With normal asymmetrical setup with the bowsprit
fully extended, the luff is the correct length, but with the tack on a normal spinnaker
pole, it's moved aft and windward, so I'm guessing the Tack distance to the head
shortened. This would mean the sail draft
would have to increase significantly to still fill.
Has anyone tried this? Does it result in a less than optimal sail shape or work perfectly? Would I need a different size and shape A sail compared to my normal Gennaker
? Any thoughts in general.....