I am designing a rig for a 42′ cruiser (monohull). Due to the nature of the hull I need a lot of sail area and a low center of effort. James Wharram, about 20 years ago, developed what he calls a “soft wing sail”. It is a gaff rig with the leading 1/4 of the sail made up as a sock which slides over the mast, in place of hoops, lacing, etc.
It’s obviously efficient aerodynamically.
My concern is that friction between the sail and mast could cause problems with reefing/dropping the sail. Wharram has been using the design now for decades and says that there is no problem, that it can be dropped on any point of sail. He has lots of boats sailing with this rig.
It seems to me that if this works on a cat it should work on a mono as well. I’ve crunched the numbers on rigging loads and mast compression and these can be made to work.
I’d greatly appreciate your thoughts any any experience you have to share on how this rig might work on a mono.
Leading edge socks have been around for many years. We used a version of this on a C-class cat in 1968. They are efficient, but bring a lot of baggage with them in terms of reefing, friction, cost, and complexity.
Some of the early free standing rigs tried to develop this approach, but ran into the practical problems above. If you are cruising locally, and into tinkering, might be an interesting project with which to play.
But my feeling is that for a long distance cruising boat they are not suitable.