Aero-rig benefits?

[C08]

Was at Millbrook and spotted the catamaran of a venerable forum member and after sucumbing to a serious spell of boat envy started looking at the aerorig set up. I know nothing about these and I wonder what the benefits and downsides are to this rig compared to a traditional bemuda rig?

 

[Woodlouse]

Downsides are weight windage and cost. Modern materials can offset the weight penalty. But for the same price or less you could have a lighter conventional rig.

I'm sure said venerable forum member will be along to express the vertues of such a set up.

 

[Twister_Ken]

Benefit. No one knows whether you're coming or going.

 

[30boat]

A friend of mine sailed an Aero rig 60f footer from Vigo to Portimão last weekend.It was very windy but he said he loved it.A very easy to sail boat.

 

[Sybarite]

Was at Millbrook and spotted the catamaran of a venerable forum member and after sucumbing to a serious spell of boat envy started looking at the aerorig set up. I know nothing about these and I wonder what the benefits and downsides are to this rig compared to a traditional bemuda rig?

A test was carried out some years ago by a French magazine on two Bénéteau 42's, one with a conventional rig and the other with an aerorig.

A test of two Beneteau 42s7's differing only in the Aerorig on one corroborates the predicted performance advantage or the Aerorig. Even though the boat with the Aerorig had 15% less sail area, it performed 10% faster upwind and 30% faster off the wind in 10 to 20 knot winds. (http://www.barbara-ann.net/vpp_results.htm)


Carbospars got into difficulty when they botched the building of one rig. Instead of scrapping it, they added additional layers with the result that the rig weighed nearly twice its design weight, with a consequent adverse effect on performance. They did not survive the resulting legal issue.

Although the mast was more expensive there was a significant saving in the price of rigging and winches meaning that the final difference was not all that much.

Conceptually IMHO it is the ideal cruising rig especially regarding the simplification of downwind sailing : just square off the rig.

It's a pity it's not more widespread as volume would bring the unit price down.


Here's what the venerable member said 10 years ago:




from the horse\'s mouth...



i have a freewing which is just like an aerorig but the mast is a wing section and rotates independantly. that makes it a bit more efficient but most of the advantages are common:

gybing is easy as the jib acts as a damper, also no shrouds to hit so you can let it go right round & it doesn't stop with a crash.

when running you square the rig across the boat, fully efficient and no risk of gybe, when a squall gets up you just ease out, till it's right out over the bow if necessary, then haul in when the wind eases.

fully self tacking, short tack up a narrow channel by just turning the wheel

the biggest advantage, which i now couldn't live without, is the ability to reef by turning downwind, letting go the sheets and allowing the rig to weathercock, no more rounding up into a rising gale.
no risk of dismasting through rigging failure

much faster on a reach than conventional, slot effect remains as sails always sheeted flat.

stresses on the hull from the unstayed rig are actually less than on a conventional rig.

the down side is cost, it's a lot more expensive than a conventional rig though you do save a lot on deck gear, especially winches.

there is no possibility of running controls back to the cockpit because of the rotation so sail handling has to be done on deck.

as has been said, carbospars has gone belly up recently but you can still get the freewing (which is cheaper) see <A target="_blank" HREF=http://www.freewingmasts.co.uk/>http://www.freewingmasts.co.uk/</A>

 

[robertj]

I'm not sure if it was carbo sails but I did look over one in Plymouth with my late Father.
Apart from looking so unwieldy the control side of things were very apparent. It performed very well indeed for the light winds close hauled and off the wind all good but on thing stuck in my mind to this day was stopping. The boat could brought to a halt just like under engine the restarted with a flick of the joystick.

 

[Seajet]

There are a few aero rig dinghy Challenger trimarans at my club, we have a large ' sailability ' section, for the disabled.

These rigs are easy to handle, though may not appeal to racing performance types.

 

[snowleopard]

As predicted, here I am again. My previous comments stand but a few more points...

These rigs are easy to handle, though may not appeal to racing performance types.

In the 1930s someone put an early version of the Aerorig on a Bembridge Redwing. after a season or two it was banned - because it kept winning all the races. How the handicappers deal with them is another story. It is limited to a non-overlapping jib and spinnakers are seldom used. I have just two sails.

It's a bit of an academic question these days as they are no longer made though you can still get a Freewing. The massive cost of the Aerorig was partly in the hardware = it used a hydraulic back and forestay to maintain jib luff tension with a flexible spar.

 

[snowleopard]

I'm not sure if it was carbo sails but I did look over one in Plymouth with my late Father.
Apart from looking so unwieldy the control side of things were very apparent. It performed very well indeed for the light winds close hauled and off the wind all good but on thing stuck in my mind to this day was stopping. The boat could brought to a halt just like under engine the restarted with a flick of the joystick.

That sounds more like a Walker Wingsail.

 

[snowleopard]

Benefit. No one knows whether you're coming or going.

Indeed. You can sail as fast backwards as forwards.

 

[bigwow]

I would imagine the join between the unstayed rig and the coachroof would be the biggest worry as the stresses must be enormous.

 

[snowleopard]

I would imagine the join between the unstayed rig and the coachroof would be the biggest worry as the stresses must be enormous.

There is no stress on the coachroof as all the load is taken by a pyramid built up from the main beam. Everyone assumes that the loads are huge but in fact they are no higher than a conventional rig. Remember that the tension in the shrouds is trying to push the heel of the mast out through the bottom. In an unstayed rig the forces are horizontal instead of vertical and the magnitude is pretty small, e.g. at the maximum heeling force, when a hull starts to fly, the load at the foot of the mast is just 7 tonnes.

 

[Poignard]

I think one of the major problems with anything unconventional, be it house, car, yacht or whatever, is likely to be the difficulty of selling it.

This is a pity, because it tends to discourage innovation and development.

 

[Seajet]

Snowleopard,

I remember reading about the Redwings and aerorigs, I suspect the high costs are with big boats and carbon fibre, the dinghy ' sailability ' jobs seem to get on OK ?

I'd like to see such a boat go as fast backwards as forwards, hull shape might have a bearing !

I saw the Walker Wingsail project boat abandoned ashore, interesting idea but the 1960's technology was lacking.

 

[snowleopard]

I suspect the high costs are with big boats and carbon fibre, the dinghy ' sailability ' jobs seem to get on OK ?

Yes, the bigger sizes take a lot of carbon. The pillar that supports mine has walls of solid carbon an inch thick.

I'd like to see such a boat go as fast backwards as forwards, hull shape might have a bearing !

Wouldn't want to do it at speed or in rough water, especially with sloping transoms.

I saw the Walker Wingsail project boat abandoned ashore, interesting idea but the 1960's technology was lacking.

Too much sail area in heavy weather, not enough in light. Of the half dozen still sailing I believe only one still has a computerised control system, the rest have reverted to manual. I was impressed though by how well the rig weathercocks.

.

 

[Sybarite]

.

http://www.voilesetvoiliers.com/gra...e-3-matin-bleu-la-goelette-ailee-en-question/

http://www.voilesetvoiliers.com/popup/media_id=8742/

This schooner-rigged boat is featured in this month’s Voile et Voiliers.

Rather than having a spar in front of the mast supporting the jib, flexible battens are used to create a “fat” sail around the mast. The batten provides a sail shape which gives the same type of lift as flaps on the wings of a plane.

The whole rig is controlled by two tiny winches in the cockpit. The boat is nine years old, has sailed over 60000 nm without problems – except that the crew say that they don’t have enough to do.


Another boat reviewed : an Elan 37 with a wing sail.

http://www.google.fr/imgres?q=voile...w=190&start=0&ndsp=46&ved=1t:429,r:3,s:0,i:92

 

[lw395]

Aero-rig type arrangements are very common in radio control yachts.
I assume that's because they don't mask the jib down wind.
Moving the tack of the jib to windward does not seem to me to be a recipe for sailing well close to the wind.
I don't believe they've figured in any 'no rules' racing or record breaking?

Wing sails are a separate animal, having serious racing history in Catamarans since the late 60's.

 

[robertj]

That sounds more like a Walker Wingsail.

then I stand corrected.

 

[LittleSister]

A
It's a bit of an academic question these days as [Aerorigs] are no longer made though you can still get a Freewing. The massive cost of the Aerorig was partly in the hardware = it used a hydraulic back and forestay to maintain jib luff tension with a flexible spar.

So what's the difference between a Freewing and an Aerorig? And may we see a pic of yours?

 

[snowleopard]

So what's the difference between a Freewing and an Aerorig? And may we see a pic of yours?

The Aerorig is one solid assembly and the mast is of fairly conventional cross-section. The Aerorig is in 3 parts - a short pillar attached to the boat, a boom assembly pivoted on the pillar and a freely-rotating wing sitting on top of the boom. The mainsail pulls the wing to one side or the other to form an aerofoil leading edge. You can sail on just the mast of the Aerorig so it also serves as a storm sail (I have done 9 knots under mast).

http://www.freewingmasts.co.uk/