Came accross this interesting article on another forum, it seems to be saying that the biggest drag on a multihull is the drag of the hull in the air. If this is so then why do we see such a speed advantage in flying the hull.
WIND
Sail lift - lbs 3610
Total air drag 1013
Sail and rig drag 361
Air drag of hull 652
WATER
Keel lift 3610
Total drag 687
Keel only drag 176
Hull drag (from tank testing) 511
This shows that for a multilhull the largest single contributor to drag is the windage of the hull in the air, followed by the hull in the water
from
http://www.steamradio.com/JSYD/Dogstar50-article.htmlIt is for a 50ft multihull, but I don't see any reason why it shouldn't scale.
Gareth
