A class results from Hop

Any results yet from Lake Hopatcong Yacht Club, NJ? Did the wing sail stay upright?

Matt

I am also interested to know how the wing did!

I think it's this one: http://bp1.blogger.com/_mLM5Q9YpULE/RwBfvQZKX3I/AAAAAAAAAAc/CfXVrbhXwCc/s1600-h/LHYC+results.bmp

What happened in the last race to have only half the fleet finish?

Sunday the wind was light and the lake had lots of holes. The SI gave the fleet 30 minutes to finish after the first boat. Fred, Charlie and a couple others were within a boat length of the finish and the race committee called the race. I gave up and got a tow in. The DNF's either gave up and went in or didnt finish within that 30 minute window. We only got one race off on Sunday.

Sat we had a range of wind starting out rather puffy (20 on/5 off) and settling down to a more managable 5-10 knot wind by the third race. 3 Races on Sat.

Friday we had good wind in the afternoon for the clinic with Lars. We did start drills and mini races.

Overall a great regatta, great people, great party, and interesting wind, very shifty and lots of holes, even when its windy. It was easy to sail into a hole and get stuck. Big shifts at the start made the starts interesting.

The wing didnt win, although Ben is very fast. The top section came off in the last race on Sat and Ben had to go in. When I asked him about it he said something about the tape coming off. He didnt capsize and on Sat when it was windy and puffy I was pacing him upwind on the first beat. Once we went around the top mark he was gone, way deeper and faster. He said later that upwind he was pinching and needed to put the bow down and go. It was puffy enough that it was probably better to play it safe. I predict that Ben will be fast at North Americans, but he's still got to beat some really great sailors. It was very thrilling to go upwind with him and down was fun too until he got away from me.

Great regatta.

Bill

Bill,
as your the first guy Ive seen here who was there, did the LR2 put in a good performance or is it just a hyped dud?
Q

Questioner,

Neither, it looks to me that it did as a normal A-cat design would have.

In the VERY preliminary results so far there is no basis to conclude that it is either significantly better or significantly worse. As such the result can at best be considered a draw.

Far more races will need to be run to determine which of the three possible outcomes it is.

Wouter

Here's my impression of the LR2, based on watching both Ian and Fred sail, looking at the boat on land and talking to John L.

The build quality is great, John does quality work. The daggers and rudders are so low aspect they are almost swords. It has no deck and I would think that this makes it slower in hiking conditions when you would want to sit and lean out on the deck. I would add a deck and this would also allow you to trap out further, by at least 4 inches. I think that would make a big differience. You might connect the outboard beams with some flaired in deck that might give it an even more radical appearance.

In the water it went well, Ian is a good sailor, so I didnt see him much, he was usually ahead of me. He did a horizon job in race 2 on the whole fleet upwind, but that was because the wind swung way right at the start and the whole fleet got caught on the line in irons and he was able to tack out of it and go speeding away up the right side.

Fred and I spent some time going downwind in 5knots and he was very smooth and the boat cut through the water well. He's got a stylish position downwind and lays on the tramp on his shoulder and looks up from this prone position. At one point I was ahead of him, we were going upwind in light air and a powerboat wake got us both. My boat did the slam, slam routine, Fred's didnt slam as much and I think he gained on me a little. The V in the forward bow cut the wake a bit, while my boat is flatter up front in the low bow, so it would probably shed a wake/wave better upwind. Downwind, I think that you wouldnt be able to push it hard in heavy air, and that it might be more prone to pitchpoling. My boat has a much flatter section upfront and I notice its very hard to stick the bows in, I can sit on the front beam and not worry about a puff downwind and I dont have to sit on the travelor like you do in the A2/A3 in heavy air. Lars and I are about the same weight and he has to sit on the travelor downwind in heavy air. I think you would have to do this as well in the LR2 since it doesnt have the volume down low. This comes from listening to Lars speak during his seminar he gave us and thinking that I didnt have to do that in my boat.

Its nice to see a designer and a builder doing something radical. John and Ian were not expecting this design, but John went with it. Ian was looking to do a next version on a flat bottom boat he once sailed. So, kudo's to both John and Ian building something radical and also somewhat unexpected from their designer.

Its not a dud, its probably better in light to moderate wind, as opposed to heavy air. It will probably be the same as the A2/A3 downwind in heavy air and want to stick the bow in a bit.

I take back my previous unflattering comment. Nice work John.

Bill

What an interesting class! Solid wing going deep and fast down wind and a new hull shape holding onto the top boats and maybe being competitive....!!!!

Could a cloth sail be split like that? What makes it go deeper and can a simpler less bulky tech do the same job?

Does everyone want scimitars for boards?

I hope they don't ban that wing....that would be gutless....go "A"s!...fight it out and keep the rest of us watching you.

I have posted this else ware, but here is a link to some update to my site.
http://mysite.verizon.net/vze28w8n/

As an outside observer (former 18sq. skipper/builder)
it looks as though the new LR2 will be a design to be watched. As far as the wing boat it looks that it need
some more development and it will be a winner. You have to remember that the 18sq Wild Turkey was built by a team that
had build and campaigned two ICCC wing boats before Wild Turkey was started.

I believe it to be exactly the other way around. Watch the wing closely and check out the LR2 occasionally. Ben Hall is at the bottom of the learning curve concerning wing sails. Ian Lindahl is however well ahead in the learning curve with his conventional rig and the hulls are simply not that important overall. I expect Ben to make lots of progress therefor while Ian's is expected to be limited.

Wouter

I agree with the Woutman.

Keep an eye on the wing as well the platform it is riding on.

Bill

Why is the wing more efficient, is it because it doesn't deform?

It deforms. I believe it is generally considered that wing sails have less drag, hence more speed.

A true wing has more differential pressure, from the lee side to the windward side, than a soft sail. More pressure diff. = more lift = more drive = faster, as long as you can control it. The biggest issue is to sail it (or Fly it) without stalling it, which would create much more drag.

Find your answers here: http://www.sailinganarchy.com/forums/index.php?showtopic=59168&st=100&start=100

Pay close attention whatever Steve Clark and Basiliscus says

Yes, unlike an airplane wing it needs to tack and sail in two directions. Kind of like being able to fly and airplane upside down and right side up and change at a moments notice.

I believe one of the more important benefits of the wingsail WITH slots is that it can perform optimally at larger angles of attack and thus make use of high lift coefficients without stalling or seeing high drag coefficients. This is something a soft sail is less suited for.

Now this won't help you too much upwind where the angles of attack are basically around 15 to 20 degrees and you experience very high airflow velocities (200% windspeed). Here you want low lift coefficients and low angles of attack.

However on the downwind legs this all changes. Here you want to have very high lift coefficients as the airflow velocities are so much lower (75% windspeed) and you have to achieve this at angles of attack that are around 60 degrees.

Basically the solid wing has a much larger range of optimal operating conditions then a soft sail.

Wouter

Wouter, I don't think your posts are even in english half the time.

You understand alot of physics that I couldn't hope to.

First concept is that a sail is sucking you forward. The wind isnt necessarily pushing you, the lift created by the differiences in pressure as it goes around the mast and over the sail suck you forward. This is called lift and its how we all go upwind so well.

Now to create more lift you need a rounder sail shape. Once the wind speed increases you need less power and you flatten your sail by having less rotation and more sheet on.

Wings do all that better and allow for slots and other mechanisms that allow the airflow to attach to the surface better, and create a more efficient sucking or lift. This also allows for the wing to operate at higher angles of attack (more round sail shape) than a soft sail can get to.

Acat go upwind really well because the sail is very efficient. Downwind Acats need to gybe down the course at very hot angles because they dont have spins. When an Acat is going downwind the travelor is all the way out, the mast rotator is off (all the way out) and the outhaul an downhaul are also off. This gives you a very full, round sail shape and creates more power or lift downwind.

The wing sail does this better because it can be basically turned sideways on the boat. This allows Ben to go downwind deeper and faster, while the rest of us mortals need to go less deep and probably less fast. Our vmg isnt as good as Ben's.

If you are having trouble picturing whats going on think about what happens on an airplane wing. The the plane is taking off and landing the flaps are down (high angle of attack) and extended aft. This creates more lift and power. The path the air has to travel to get over the top of the wing is very round.

When the plane is up to speed the flaps are moved up and into the wing. Since you dont want to fly around at take off speed, the wing needs to change its shape to allow the plane to go faster. The flaps are moved forward and up and this is a less round path the air needs to take (lower angle of attack)

Next time you are on a plane get a window seat by the wing.

Now go re-read Wouters post and then you'll be ready to read the posts on sailinganarchy.

Bill

Btw Wouter, I though your anwser was concise and well worded.

Thank you Bill.


correction :

Quote of "60 degrees" should be replaced by "over 30 degrees", basically 30 to 45 degrees depending on some details.

I had to do some quite calculations and took the wrong angle when writing my initial posting. Any wing will stall at 60 degrees angle of attack (even delta wings), so I should have spotted that immediately.

Sorry,

Wouter

I agree, Wouter - nicely well worded reply.

Bill - one minor point:


The flaps increase the camber, not the angle of attack. More camber creates more lift at higher angles of attack (without stalling), but at the expense of greater drag. The extended flaps (and leading edge slats) also introduce a slot that helps the airflow remain attached (not stall), as does the slot on the sailing wing.

OK, now that we have that sorted out, let's start talking about Vortex Generators... <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

And Bill, all top level competition aerobatic aircraft use completely symetrical wings now, they fly just as well upside down as right-side up, same as Ben's Wing has to be symetrical for use on each tack. The difference is Ben has a slotted flap that he uses to change the camber to asymetric, on each tack. The competition acro planes do not use flaps. (Google up a good picture of a Sukoi 31 wing)

Matt,
I wasnt going to introduce the concept of camber, but you are right, wing on planes dont rotate.

And Timbo, thats interesting, I didn't know that.

I've always been able to relate whats going on with a modern wing mast with whats happening on a passenger jet. Probably because I spend so much time on passenger planes.

Well, passenger jets only have to fly right side up, but the competition acro stuff has to do both, changing the angle of attack gives one side of the wing more lift, thus they can fly with a 100% symetrical airfoil. If you put a big enough engine on it, you can make a barn door fly, but they had to put two of them on the F4! <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

Inside joke for any of you sled drivers out there.

Our soft sails are akin to the Wright Bro's. early cloth covered wings. Wing development has come a long way in the past 100+ years, but we are still using soft wing technology. It does add to ease of use (you can roll them up and put them in a sock) and keep our costs down.

Who wants to be a "Wing Sherpa" at a regatta and buy a huge box to carry it in? Not too many, so I predict the Wing, while being obviously better ie. generating more lift, will not catch on in large numbers. Too cumbersome to transport, might be too fragile if you land on it in a capsize... and too expensive to replace if (excuxe me, I meant WHEN) you break it. <img src="http://www.catsailor.com/forums/images/graemlins/blush.gif" alt="" />

Can the wing rigged cat be righted solo after a capsize? Has this been tried, or tested? Furthermore, if one should pitchpole in big air, how likely is the mast to stay in one piece?

maybe this

WOW
That's really flying a hull to the limit. <img src="http://www.catsailor.com/forums/images/graemlins/ooo.gif" alt="" />
And check the guy doing a hand stand on the upper hull.
Those kids and their wacky toys!

Man, that looks fast, what with the reduced drag by keeping only one hull in the water and the lift from the sideways wing...and check out that trapeeze style, upside down and backwards! <img src="http://www.catsailor.com/forums/images/graemlins/shocked.gif" alt="" />

thanks for all those pics lesburn1, very interesting to see close ups of things people are talking about here, like those narrow daggers, rudders and of course the wing

in the oops pics you have what looks to be the wreckage of a homebuilt? ply cat called "kiwi magic"

what happened to it, stress failure, collision?

long way to bring a boat from new zealand to have that happen to it

eric e

http://www.catsailor.com/forums/sho...umber=120051&page=1&vc=1

http://share.shutterfly.com/action/...p;amp;emid=sharshar&linkid=link4

lots of pics from the Hop.

According to the online book "See How It Flies" from John Denker, flaps increase the camber and the angle of attack.

He uses the definition of angle of attack as being the angle of the wing relative to a position where it would provide zero lift. Your definition might be different.