MaSt aft rig

[pironiero 93]

if foresails are more efficient- why mast aft rigs are not used in competitive sailing?

[Jethrow 411]

because they're not more efficient. Just about every development dinghy and multihull class tends towards just a mainsail or a big main/ small jib combination.

[MRS OCTOPUS 202]

1 hour ago, pironiero said:

if foresails are more efficient- why mast aft rigs are not used in competitive sailing?

Efficiency is subjective.

Certainly large headsails are not efficient to windward over a wide wind range.

Reaching is a different story.

Very easy to reef a large roller furled headsails on a cruiser.

Some IMOCA 60s have the mast stepped a fair way back from the bow and set some pretty big headsails at times.

[Somebody Else 896]

Horses for courses

[Navig8tor 1,782]

And you forget racing rules

70-80’s rigs were primarily headsail driven boats with small blade mains, if your took the main away the bulk of boat speed was from the headsail.

Mains got bigger and headsails provided gears for conditions.

Now masts have got further Aft, J measurements larger but sheeting angles even tighter, great sailing but I feel some trickledown effect will not necessarily trickle down because you still have racing boats and cruising boats and then the older boats were not geared to finer sheeting angles.

[LeoV 3,152]

[Voiled 209]

[Steam Flyer 8,441]

I saw racing dhows in Bahrain back in the 1980s, they were nothing like you see in the history books but they were not yet the full-carbon machines you can see on YouTube now. The rigs were powerful and although I never got to sail one, I was itching to try.

- DSK

[10thTonner 475]

[JimC 1,029]

Its very complicated, like most things with rig design. It is true to say that in a sloop rig there is more power per sq foot in the headsail than the mainsail, but that is solely because of the two sails interacting. Take the mainsail away and the effect is lost. Then the planform of a headsail must intrinsically create more induced drag than a battened mainsail, and the twist control of a headsail is problematic. 

All this means mast aft rigs are very inefficient, which is why they aren't used in racing. The mast aft enthusiasts are a very odd bunch, and are of the style of ultra-enthusiast that discards any information that doesn't match their preconceptions. They have a bunch of half truths, misunderstandings and misconceptions that they regularly trot out out. 

 

 

 

[pironiero 93]

Thanks guys!

[floater 696]

On 11/28/2021 at 2:36 AM, Voiled said:

you don't see that everyday. check out the canting rig - and not sure what else is going on there.

[Voiled 209]

4 hours ago, floater said:

you don't see that everyday. check out the canting rig - and not sure what else is going on there.

These boats are awesome, to see some more of what's going on check this tack at 1:15

edit: video with more pixels and a tack at 9:18

 

 

[floater 696]

now that's how to put some weight on the rail. :-)