Wingsail shrouds

[Trudel.s]

Hi guys,

I'm designing a wingsail on a F18 cat for a university project and I have a question.

The wing will have no flap, therefore we keep the front sails of the boat. We think of attaching the wing with 3 shrouds (one fixed on each hulls and a center one holding the gennaker). For us to be able to rotate the wing, the shrouds must not rotate with it, so they need to be fixed on some pivot. Currently, I'm puzzled on what's the best way to do it. I know AC45 have a shroud config. similar to ours, but I cannot find the info on how they join the shrouds to the wing.

So, if anyone knows what's the best way to do it, please tell me.

Thanks a lot for your time!

[Doug Lord]

Originally Posted by Trudel.s

Hi guys,

I'm designing a wingsail on a F18 cat for a university project and I have a question.

The wing will have no flap, therefore we keep the front sails of the boat. We think of attaching the wing with 3 shrouds (one fixed on each hulls and a center one holding the gennaker). For us to be able to rotate the wing, the shrouds must not rotate with it, so they need to be fixed on some pivot. Currently, I'm puzzled on what's the best way to do it. I know AC45 have a shroud config. similar to ours, but I cannot find the info on how they join the shrouds to the wing.

So, if anyone knows what's the best way to do it, please tell me.

Thanks a lot for your time!

-----------------------------
Look in "Understanding Wing Technology" toward the end for a bit from Steve Clark on wing mast rotation that may help. The thread is in the "Aerodynamics and Hydrodynamics" section of the forum. I'll try to provide a link later.

[Trudel.s]

Thanks, I took a look at it.

To be more precise, our wing's pivot is at the 1/4th chord. So, the hounds should rotate about this point, right?

[Doug Lord]

Here is the info: Understanding Wing Technology
post 148

[Trudel.s]

Alright, thanks a lot. Lots of good info there.

I think we won't have to build this type of track for our sail, because our sail is in 2 parts (for transportation) and we think of attaching the hounds at the junction, so there'll be a gap where we could place a rotating plate.