Originally Posted by
sleddog
A book could be written on this subject.
Dedicated twin jibs of light weight spinnaker cloth (.75 oz - 1.5 oz.) are as stable as a spinnaker. Heavier and flatter wung out jibs, like a #2, cause increased side to side rolling. In any case, when running DDW with twins, no matter what the brand of autopilot or self steering, the boat will likely yaw 15-20 degrees either side of course. But with the main furled, there is no worry of an accidental jibe.
Twins are arguably better for displacement boats with roller furling compared with lighter designs that pick up significant speed under spinnaker when sailing on a broad reach (AWA 130-160). Unless your AP is really good, you're gonna have to hand steer and tend the sheet with a spinnaker for long hours. Not so with twins.
Back in the day....
Doug Graham on Big Dot, his Yankee Dolphin 24, did a SHTP in 1996 with no spinnaker and flew twins, instead. Note that he won his division and corrected out 2nd overall if I remember rightly. I remember watching Big Dot coming down the estuary flying twins, in dead last place during a race many years ago....but he was moving.
You can read about Doug and Big Dot on the Dolphin 24 website - http://www.dolphin24.org/stories_big_dot.html
If you watch this old Kite-Cam video from SSS'er and 2x SHTP vet, Chris Humann, you'll see his boat, a Dana 24 under dedicated, custom-made twins, with the mainsail down in mid-Pacific.
I think the success of twins depends somewhat on the nature of the boat.
Last edited by AlanH; 07-20-2017 at 12:24 PM.
1968 Selmer Series 9 B-flat and A clarinets
1962 Buesher "Aristocrat" tenor saxophone
Piper One Design 24, Hull #35; "Alpha"