I'm just wondering if anyone has tried modifing the sail to accomodate conventional shrouds. Instead of or even with the mast helper, make a cutout in the sail 2/3 up the mast and add a clamp to harness the shrouds. Similar to a conventional sailboat. This would keep the mast from bending or twisting.

Im not sure how performance would be affected but I think durablility and safety could be.

Regarding durability, the stayed sail/mast generating lift creates a big down force at the mast base. However, with the mast helper, the down force is distributed between the mast bottom and the bottom of the mast helper. Ive heard that windsurfing mast stayed up high can "explode" while sailing and this doesnt happen with the mast helper config as used on the ice flyer. However, the mast helper does put a load at the point where it contacts the mast but this is also where the mast is normally beefed up to handle the loads of the boom. If the mast is stiffened with an extra top peice slide inside the mast, they pretty much dont break when used with the mast helper.

Regarding safety, you can tip over an ice flyer (partly because they are fun to sail in high winds with too big of a sail). If you have the mast stayed up high and you break the mast in a tip over.. well, it wouldnt be a good safe thing to do. However, if the mast helper and stay arrangement is strong, you could break the mast and the helper arrangment still gives you a roll bar.

Performance wise, who knows but it would probably be a big unkown since they sails were not designed to be used this way. I think you get a fair amount of extra drag from the longer stays (there are three of them). The isabella ice boat design (also uses a windsurfing sail) started out with he stays up high on the mast but seems like a lot of them have migrated to a configuration similar to the ice flyer mast helper. However, I dont know why they did this but it might be a good source to ask.

Finally, the reason for the design being the way it is in the first place was to allow any windsurfing sail to be used without much hassle.

Dont want to damper any experiments you might be doing so I would say the main thing would be to keep the safety consideration in mind in case of a flip over.

Regards,

Wh