AC Wings

Started by Bee, November 10, 2009, 01:52:27 PM

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Bee

If you have not yet done so, go check out SA.

Bee

OK, I am impressed.  A 190 foot wing (oh, I mean hard sail) on a 90 foot square (almost anyway) platform that pushes the tri at 32 mph in 10 knots of breeze.  No doubt a technical accomplishment of the first magnitude.  Only questions: Can they transport it?  Is it strong enough?  What does it take to break it? Can you imagine trimming this thing? 

How about some local multi-hull sailor input.  Looks to me like this is your moment to shine.

So what's SNG's response to this?  Another law suit?  A major change of venue?  If they hang on to the "no race in winds greater than 15 knots" it would appear that they are out of luck.

Amazing what several hundred million dollars will do.

Christopher

Mahalo nui loa

edthemainsailguy

I thought it was actually easier to trim because the shape of the foil is fixed..seems like i read that somewhere

BJSailor

I had a tad bit of experience with these in '87-'88.  Easy to set up and sail - difficult to get to go fast.  The hard thing is changing gears.

The basic principal is relatively straightforward.  The hard sail is a cleaner airfoil and the basic lift/drag and angle of attack are relatively predictable.  I don't want to say that any aerodynamic engineer could figure it out, but the theory and practice have been in use for over 100 years.

The challenge is creating an airfoil that is effective and efficient at low windspeeds and is dynamaically adjustable to trim for different windspeeds and directions with height above waterline (we call it twist).  If you'll remember, Stars & Stripes ended up sailing with soft sails for the Cup.
There are 10 types of people in this world - those that understand Binary, and those that don't.

Bee

I do understand all that Brian, but have you actually sailed one anywhere near this advanced?  I am actually stunned that they got 32 mph in 10mph of wind.  I understand the physics of that as well but still 3.2 times wind speed is almost unbelievable.  If that thing could handle it it would produce 50 mph in just 15.624 mph of breeze! At that speed it would cover 6000 miles in just 5 days!

My guess is that the wing was designed with a tremendous amount of computer simulation.  Maybe even some super wind tunnel tests.  Of course I would like to know what, why, and how, but nevertheless, the engineering required to just get this thing built and up is unbelievable.

ChrisK

#6
So if the technology trickles down, 10 years from now I'll never have to buy 'cloth' sails again? Just retrofit mast and sails with a wing? Could this be a million dollar idea? You heard it here first. LOL

Interesting to see the 1988 wing was designed by Scaled Composites. Aviation types know what I'm talking about.
http://www.scientificamerican.com/article.cfm?id=americas-cup-fixed-wing-sail

The upcoming Americas Cup, with these exotic machines, with hopefully bring alot of much needed attention to our sport and maybe even bring in some new sailors (Rum Race anyone?)

If the coverage is good (ESPN?) and they keep it out of the courtroom, expect to have alot of conversation about the America's Cup around the company water cooler in 2010.
Past Commodore, 2010

BJSailor

Bee, I don't think anyone in this world sailed anything this advanced until this week!  It's an amazing piece of technology. 

I've got a bit of a background in aerodynamics and that served me well in an effort back in the late 80's with another hard sail - even got a number of rides...  Lately, the only real effort in hard sails has been in the A-Cat class.  I was fortunate enough to get an in-depth interview with Ben Hall who sailed a hard sail at the A-Cat Worlds in FL a couple of years ago.  He and I spend a couple of hours both on the boat and at the bar drawing diagrams and talking technical stuff.  His hard sail rig was simple in concept, but complex in construction and new to everyone in trimming.  I beleive Ben finished in the top 25% in that Worlds sailing a hard sail.

Multihulls especially frequently sail at multiples of the true windspeed.  Sailing at a 3.2 multiple is amazing but not unheard of if the boat is on its fastest point of sail.  If I remember correctly, Hydropere (sp?) broke the absolute speed record topping 50kn in a tri with cloth sails in about 20kn true wind.

Whatever...  We'll all see how this hard sail works soon.  I'm curious whether Oracle will actually sail with it in the AC.  Tearing a jib is easy to repair / replace, but breaking the wing will be a disaster.  I hope they have Plan B handy.
There are 10 types of people in this world - those that understand Binary, and those that don't.

KevinBednar

I bet they're doing it to "one up" the Allinghi guys.  This race is currently being sailed in winds made of money...

Bee

SA if full of comments about one-upmanship and right now the big money bet is on BMWO.  Still, I would like to know more about how they did the simulations.

Keith

It broke

And did someone actually compare this technology to the late 80's??

Stars and stripes could have sailed the original cat with a canvas sail and still won the A-Cup you are talking about.

STuma

The hard wing is incredibly efficient... the problem is storage...  The C-cats and S&S 87 had to store the boat on it's side...  this has always been the problem with hard wings, storage... I remember a friend of mine being anchored near "Royale", a 87' offshore maxi-cat, in 30 knots of wind...  this boat only had a large wing mast... He didn't sleep all night because the boat would sail up on it's anchor; first one tack and then the next... He thought the boat jumped from 0-20 knots instantly...  the load on the hard wings are so much less than soft sails, the sheet runs horizontal instead of mainly vertical...  Yea, S&S 87 could, and should have, run the soft sails and still won... But, do you go for the guaranteed win or the predicted win?
cheers...
Scott