Beating Questions

[Dockhead]

Originally Posted by alan_za

120-130 degrees tacking angle?? Better follow the trade winds on that cruise and hope you never have to beat Angle that the boat tacks through is a pretty bad indicator since so many other factors can influence your boat speed and hence the apparent wind and hence the angle after tacking.

I think he's talking about tacking angle on the GPS.

Yes, with those kinds of angles, you are hard pressed to make any miles dead upwind, but that is the reality for many cruising boats, especially old ones with old sails and inefficient underbody designs -- like my old boat.

You do more motoring, that's all.

[zydecotoad]

Boulter,

From an engineering/design perspective, the boat characteristic that allows good windward performance is LOW DRAG.

DRAG is produced both in the air and in the water. Drag in either is seperated into 3 types for design purposes.
1) Form drag, caused by just pullin the hull/rig through the water/air.
2) Induced drag, a side effect from generating lift (forward force on the sails, lateral resistance from the keel )
3) friction drag

Form drag is reduced by having the smallest possible hull in the water and the least windage above the waterline.

Induced drag is reduced by having high aspect ratio rig and keel.

Friction drag is reduced by having a smooth bottom.

Anything that you can do to reduce drag will improve windward performance. Anything that adds drag will reduce windward performance.