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Old 18th June 2011, 02:42 AM   #22
Floyd
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Join Date: Sep 2006
Posts: 459
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Ken
Agree with you about all points except tail walk.

Tail walk is a result of board producing more lift than load;it lifts up;lift drops ;it drops . In effect board is too wide and it can no longer reduce its wetted area to a point where balance would be achieved. Its why boards with high tail rocker (ie wave boards) do not tail walk. They just carry on reducing wetted area; planing on a smaller and smaller area. Its exactly why cut outs were introduced; a way of reducing area at rear of board but still maintaining width for leverage on fin.There is no way on earth a vertical fin can produce lift against gravity.It must be inclined to produce actual lift. Bigger incline ;the more the lift.(ie at 45 degrees lift would be distributed half against lift ;half against leeway..
And even when inclined it can only produce lift in one direction.ie it must try and flip board.It needs an angle of attack to produce any force.Inclined away from wind it would pull back under(actually aiding gravity!)(ie if inclined down wind it produces negative lift !!!);inclined to wind it would try and climb out of water. ie both instances rotating board in same direction !!! Sounds crazy but its how it is !!!(look up Bruce foils)
My take on things anyhow.

Last edited by Floyd; 18th June 2011 at 03:00 AM.
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