I have bought a carbon windsurfing mast to make the pole for my Taipan project hooter. I will be creating a Nacra style bridle foil with a dolphin striker for the jib and am wondering if there is any magic formular for the length of the pole and the height of the mast fixing for the hooter sail.
Rick, I know you have been through this exercise...??

Yes there is a magic formula. The texel rule states no part of the pole shall extend horizontally more than 800mm longer than the distance from your beams to the bow. This is the baseline that most cats are using today.

As far as height it has been argued that a safe distance between the tang and the mast head is anywhere from 1/3 to .65. If I remember correctly, Bill Roberts says 1/3 is the place where you can accidentally release the mainsheet with a spinnaker load and not break your mast. I can tell you that most of us do not heed this advice and use between 1/2 and .65. There is more risks involed with making mistakes when going higher.

Matt

from F18 Rules

for hooter, not spinny

what's the difference between a hooter and spinny? I actually dont know what a hooter is, I thought it was a spin :P

It is a flatter sail and roller furling. Can be sailed up wind.