Just another Moderator
Join Date: Sep 2005
Location: New Westminster, BC
Thanked 470 Times in 444 Posts
Rep Power: 10
As I understand it, the initial 'sideslipping' creates the angle of attack... as the boat picks up speed this translates into a partially compsensating lift force to windward, reducing ultimate leeway.
Excessive pinching/trying to point too high can defeat this effect (the keel can 'stall').. which is one reason why rearranging the deck plan of some boats to improve sheeting angles won't necessarily improve VMG to windward.
From discussions with my son (racing a Melges 32) failure to attach that flow to the foil really hurts because these keels have minimal lateral plane to resist leeway otherwise...
Any true experts should feel free to correct this if necessary....
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)