Is it worth tacking upwind with a Flat Earth sail?^

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Douglas Wilcox
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Is it worth tacking upwind with a Flat Earth sail?^

Post by Douglas Wilcox » Mon Sep 26, 2011 9:43 pm

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There was a 12 knot headwind blowing directly from our destination the Heads of Ayr.

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I decided to try and tack upwind to see if it would be quicker than just putting my head down and paddling straight for the Heads of Ayr.

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At first I tacked upwind while both paddling and sailing. I covered 1600m over the ground but only 600m upwind in 15.28mins. The over ground speed was 6.3km/hr but the upwind speed was only 2.4km.

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Next I dropped the sail and paddled directly upwind. I covered the next 600m in 6.72mins which meant the upwind speed was 5.4km/hr.

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It was good to take a rest at Bracken Bay and work all this out. My conclusion is that it is not worth tacking up wind when kayak sailing but if you can lay your destination sailing closehauled it is worth kayak sailing. In this example the close hauled speed was 6.3km/hr and the paddling only upwind speed was 5.4km/hr.

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Of course the downwind blast home was much more fun...

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...my maximum speed regularly went over 14km/hr with a max of 14.6

Douglas

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scotty
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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by scotty » Mon Sep 26, 2011 9:52 pm

Hi Dougas did you get a chance to compare the angles between your tacks on your compass with the angles between them on your gps track,i guess without any kind of dagger board you side slip quite a bit and maybe a hull with a deep v keel would sideslip less,only ideas looks like fun.

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Douglas Wilcox » Mon Sep 26, 2011 10:26 pm

Hello Scotty, a decent dighy with a centre board will sail about 45 degrees off the wind. I was only making 68 degrees but that is still "up wind", which I think is quite remarkable given that a sea kayak like mine does not have a centreboard or lee boards. Also quite remarkable is that it will paddle/sail up to 68 degrees from the wind at about 20% faster than you can paddle in that direction!

Douglas :o)

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Mikebelluk » Mon Sep 26, 2011 10:31 pm

Douglas, what do you think of the Delphin?

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Douglas Wilcox » Mon Sep 26, 2011 10:35 pm

Hi Mike

the Delphin is absolutely stonking!

Douglas :o)

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Jim
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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Jim » Mon Sep 26, 2011 10:37 pm

Whilst I think your overall conclusion is correct based on the upwind heading you can achieve, you're sacked as tactician.
Any fool knows that you lose speed through the tack so beating in 7 legs where 2 would have sufficed is reason enough to send you to go and dangle your legs over the side!

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by al27 » Mon Sep 26, 2011 10:53 pm

Any fool knows that you lose speed through the tack so beating in 7 legs where 2 would have sufficed is reason enough to send you to go and dangle your legs over the side!
Allowing for the wind shifts, obviously!! Don't want to go too far out on one tack, just in case......

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Jim » Mon Sep 26, 2011 11:07 pm

al27 wrote:
Any fool knows that you lose speed through the tack so beating in 7 legs where 2 would have sufficed is reason enough to send you to go and dangle your legs over the side!
Allowing for the wind shifts, obviously!! Don't want to go too far out on one tack, just in case......
Is this why I keep losing in the buggy? Oh no, that will be lack of raw pace and technically poor tacks and gybes mixed with a conservative approach where I usually allow myself too much extra room to lay the mark.....

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by PhilAyr » Mon Sep 26, 2011 11:18 pm

"I decided to try and tack upwind to see if it would be quicker than just putting my head down and paddling straight for the Heads of Ayr."

... So that's what you were up to !..... and I thought you were having problems with your skeg.. Silly me ! ;-)

Surprised that any of the photos I took came out Douglas.
Douglas Wilcox wrote:Hi Mike

the Delphin is absolutely stonking!

Douglas :o)
...... I'll second that ! :-0........Phil

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by al27 » Mon Sep 26, 2011 11:35 pm

I...... lack of raw pace and technically poor tacks and gybes mixed with a conservative approach where I usually allow myself too much extra room to lay the mark.....
Yep, sounds like most of my races.....

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Jim » Tue Sep 27, 2011 12:18 am

al27 wrote:
I...... lack of raw pace and technically poor tacks and gybes mixed with a conservative approach where I usually allow myself too much extra room to lay the mark.....
Yep, sounds like most of my races.....
At least with a mast, technically poor tacks and gybes usually don't end up with the sail in a tangled mess on the deck/in the sea :-)

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by gnarlydog » Tue Sep 27, 2011 4:48 am

Douglas, thank you for confirming (with evidence) what I have suspected for ages: it's faster to paddle alone upwind than to sail/tack/paddle. Since I don't do GPSs I never really knew what my real course was when sailing upwind.
Also nice to know what is a definitive angle of max tack (including drift) when trying to sail upwind.
Of course there might be slight variation between hull shapes (more pronounced "V" might give you a better angle? maybe a rudder could be an advantage there too?) but a sea kayak lacking a positive deep keel will never be a true sailing boat.
To me the real fun is quartering stern winds where surfing is possible to then "cut" the wave and accelerate sideways. That's when I hear my skeg hum :-)


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FEKS sailing_2_c by gnarlydog, on Flickr

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Douglas Wilcox » Tue Sep 27, 2011 10:51 am

Jim>
Any fool knows that you lose speed through the tack so beating in 7 legs where 2 would have sufficed is reason enough to send you to go and dangle your legs over the side!
Hi Jim that's usually true on open water or on the beach! However, when I was a boy I used to race Fireflies in Ayr Bay and so have the tactician's benefit of local knowledge! In an ebb tide (especially if there is a lot of flood water coming down the Ar and the Doon) and a SWly wind we used to tack up close inshore to take advantage of the ebb current sweeping round close to the southern edge of Ayr Bay. Offshore I was tacking at the edge of the brown river water and blue sea water and inshore when it got too shallow! Whatever, I couldn't catch Phil who paddled straight up wind.

I suspect the Delphin will tack much faster than your buggy, it just zips round, lift the skeg, sweep and apply a little edge and its round! It's much quicker tacking than my Nordkapp LV.

Douglas :o)

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Jim » Tue Sep 27, 2011 12:35 pm

Aha, I see.
In the buggy we rarely have to worry about current when beating, but the slope of the beach can be an important factor during a tack or a gybe, as can the firmness or softness of the sand and the smoothness of it - even with wide low pressure tyres it's amazing how much we can tear up the beach. All these factors can affect how fast you can actually go, a bit like currents and it can be hard to decide whether to go for fewer longer tacks over mixed terrain or more shorter tacks sticking to the fastest terrain.
So was your test done with the assistance of the eddy helping your upwind heading?

Tacking the buggy takes a bit of time to learn, like a boat you need to have enough forward speed to roll around the turn whilst the sail (kite) is not adding any drive, but if you have too much speed there is a danger of the front (steering) wheel losing grip and then scrubbing speed as it slides sideways instead of rolling. Generally speaking though, this can be controlled by shuffling forward to weight the wheel and taking a slightly wider turn at higher speeds, and fast tacking is better than slow tacking. I just wish I could be as consistent at it as the good guys, my usual issue is losing too much speed and struggling to re-build the apparent wind in the sail (kite) to keep going - sitting almost stationary at the point where everyone else wants to tack is quite a vulnerable feeling, fortunately I almost never stop completely these days, or let the kite luff out and plummet to the ground.

Whether it is faster or slower than tacking a Delphin I couldn't say, it must however be amazing to watch a large fleet approaching the first tack of a race (start upwind so there is usually one fairly soon) - as the leaders start to make their tacks others find themselves running out of space ahead and have to react by tacking underneath as late as possible, it sort of ripples back through the fleet!

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Yakdiver » Tue Sep 27, 2011 1:46 pm

I didn't realize that there was so much interest in kayak sailing as I have never seen any in my area.
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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Oarsome » Tue Sep 27, 2011 5:28 pm

Yakdiver wrote:I didn't realize that there was so much interest in kayak sailing as I have never seen any in my area.
Whatever you do, don't call it "cheating"!!

(lol)

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by mick m » Tue Sep 27, 2011 9:56 pm

Is the Delphin a demo boat ? or have you added it to your colection ? Im keen to give one a go , my only consern is the foot space with my long legs and size 12 feet . and ther arnt eny around hear to try , the other consern is the wait of the plastik , dont now if I can go back to hevy boats . but the size is a step in the right direction , my boat of choice is 14' with a plum bow . being skin on frame and only 15kg fullie fited out I find a standard flat earth sail a bit of a handful in a fresh wind, and with a smaller sail its more responcive and points beter , its got no ruder or skeg ether . Im going to have to get out ther with a 2 sail rig and see if it makes much diferance to taking and holding ground , I generaly find that on a long run the aft sail helps balence the rig , but is realy tiaring on proper trips and not worth the efort on enything more than a day paddel

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Douglas Wilcox » Tue Sep 27, 2011 10:23 pm

Hi Mick, the Delpin is on long term loan from P&H but already I think quite a few of us will be buying one. It surfs incredibly easily without a sail and I thought the hard chines at the bow would be ideal for shedding water with the extra drive of a sail providing the go to overtake the waves. I wasn't wrong, it's a fantastic sailing kayak. It tacks a dream due to its tight turning. For a poly kayak I didn't think it was excessively heavy at about 27kg. It's also very comfortable and my size 10 boots have plenty space.

Douglas :o)

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by chrism » Wed Sep 28, 2011 12:13 am

Jim wrote:Any fool knows that you lose speed through the tack
I presume you can't roll tack a buggy?

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Jim » Wed Sep 28, 2011 1:02 am

chrism wrote:
Jim wrote:Any fool knows that you lose speed through the tack
I presume you can't roll tack a buggy?
Er, no. Best to keep all 3 wheels on the ground all the time, besides with the kite not attached to a mast it wouldn't pump any more wind into it.
I guess in some ways tacking a kite is a bit like a roll tack in that it is best to keep the kite moving slowly over the zenith during the turn to make sure it stays inflated and also because the lines will cross and the easiest way to make sure you pull the right way to start the power dive out of the tack, is to have been gently pulling that way all the way through. Otherwise it's really easy to pull on the wrong handle due to the line twist messing with your perception!
Oh, and keeping fairly tight on the kite brakes throughout is useful to stop it getting too close to the edge (i.e. reduced AOA) where it will luff. There is actually quite a lot going on during a tack!

A major disadvantage of kites over masted sails (at least with wheels), is that a dead run is impossible, the buggy soon gets faster than wind speed and huge kite movements are needed to keep it flying faster than wind speed, to keep the pressure in the lines your track will naturally start to become a zig zag. Mind you since we can go several times the wind speed on a broad reach the only real disadvantage is in feeling for the limit with the risk of stepping past it.

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by downunder » Wed Sep 28, 2011 6:22 am

Here is a clip that may solve the problem of sailing upwind and the inherent drift to lee. It does seem a little complex though.

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Graham T » Wed Sep 28, 2011 7:12 am

Good video thank you Bill.

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Douglas Wilcox » Wed Sep 28, 2011 8:16 am

Hi Bill reading your post I thought the link was going to take me to a complex technique video! :o)

The Kayaksailor rig was one that we looked at before going for the Flat Earth rig. (We also looked at and bought a Pacific Action V rig but were disappointed in its overall sailing performance.) We decided not to try the Kayaksailor rig for several reasons. Firstly its sail area looked too big for the winds we get on our open sea conditions; it is designed for kayaks up to 94cm wide but my Nordkapp LV is 55cm wide. The videos of Kayaksailor in action are mostly light winds, flat water and in lakes where it sails very well indeed but I don't think it would have been so good on my Nordkapp LV in the bumpy force 4-5 winds Tony and I were in at the weekend. Secondly the Kayaksailor weighs 4.5kg and I did not fancy having having that weight on the foredeck of a kayak like my Nordkapp LV. The Flat Earth rig weighs 800grams. Thirdly, as you say, the Kayak Sailor is complex and we did not want to convert our kayaks into dinghies. Lastly it is expensive.

The advantages of the Flat Earth rig are its simplicity and lightness. I am willing to trade those against the Kayaksailor's extra few degrees upwind but with its disadvantages I have mentioned.

Douglas

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by downunder » Wed Sep 28, 2011 9:47 am

Hi Douglas,
Sorry for the confusing post. I would agree with you on all the points you raised. We have a couple of flat earth sails in our paddling group. I am seriously considering getting one myself for my Cetus. The only problem with that is that I will have to buy one for my wife's cetus as well.

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Bill

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by JulesT » Wed Oct 12, 2011 10:07 pm

Hi Douglas & all - I use an experimental sail but its nowhere near as efficient as the Flat Earth, there is no way I can sail upwind, probably the best I can manage is an angle of about 100 - 110 degrees to the true wind.
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I think its quite amazing that you sail at such an angle with no centreboard of any kind. I do appreciate that high speed windsurfers can go upwind with no centreboard but only a rear fin (I windsurfed with a passion for 25 years).

So I think I'll have to invest in one of these sails, in this country we sea kayakers have perhaps been conservative as the Maatsuyker paddlers of Tasmania were making and using their own for many years

So to finish its back to that old chestnut; the rudder. To get the best out of the downwind run IMHO and many others a rudder is essential. Yes one can trim the kayak with sail by using the skeg and paddle but you're never going to be able to get the manoeverability necessary to be in full control and make the best of the conditions without a rudder. Check out this fantastic recent trip by the Aussies with Rockpool Tarans and Flat Earth sails with some excellent video footage. See here for a great downwind run and here for the whole expedition. Note the epic mid-wing paddles are great for skimming over the water for gentle bracing at speed. As a footnote their preparation of the kayaks for that trip is very impressive.

Question - do the flat earth sails come in different sizes? If so which do you use and where can one get them from in the UK?
Jules

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by Douglas Wilcox » Wed Oct 12, 2011 10:41 pm

Hi Jules, like you I have been windsurfing for a while, I started in the late 70s. Mind you some upwind windsurfer skegs are pretty long and the upwind lift at speed must be considerable.

With regard to Flat Earth sails, they are available in a variety of sizes from about 0.7m2 to 1.0m2. The most common ones in the UK are 0.8sqm, which I think are ideal. You can get them from Karitek and Poole Bay Canoes.

I have sailed Valley kayaks with a skeg and a with rudder. I prefer a skeg. Yes a rudder is great off the wind but when trying to go upwind in a decent breeze the area of the rudder is so great it causes the kayak to leecock and no amount of steering will bring it back into the wind, you just end up with the rudder blade at an angle, gurgling and slowing you down.

I have fitted a Flat Earth rig to a Rockpool Alaw Bach (mine has a skeg), details here:

Jules, you will not regret it!
Douglas :o)

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by mick m » Fri Oct 14, 2011 9:32 am

JulesT wrote:Hi Douglas & all - I use an experimental sail but its nowhere near as efficient as the Flat Earth, there is no way I can sail upwind, probably the best I can manage is an angle of about 100 - 110 degrees to the true wind.
Image
I think its quite amazing that you sail at such an angle with no centreboard of any kind. I do appreciate that high speed windsurfers can go upwind with no centreboard but only a rear fin (I windsurfed with a passion for 25 years).

So I think I'll have to invest in one of these sails, in this country we sea kayakers have perhaps been conservative as the Maatsuyker paddlers of Tasmania were making and using their own for many years

So to finish its back to that old chestnut; the rudder. To get the best out of the downwind run IMHO and many others a rudder is essential. Yes one can trim the kayak with sail by using the skeg and paddle but you're never going to be able to get the manoeverability necessary to be in full control and make the best of the conditions without a rudder. Check out this fantastic recent trip by the Aussies with Rockpool Tarans and Flat Earth sails with some excellent video footage. See here for a great downwind run and here for the whole expedition. Note the epic mid-wing paddles are great for skimming over the water for gentle bracing at speed. As a footnote their preparation of the kayaks for that trip is very impressive.

Question - do the flat earth sails come in different sizes? If so which do you use and where can one get them from in the UK?
Thats one big bit of sail !!!!
Im just back from a week off, only spent a day 1/2 on the water in a kayak, but did get a chance to test a new design , and it impresed me , at .75m sqr it had all the drive of the old duwell batern sail, and was very polite in stiff winds with a realy good seting ability , just set it and forget , its got less twist so its more responcive, close haled it wont point a high, but with the conventional sail what you gain I think you loos with side slip of the kayak. I was yousing my big expodition boat, with a ruder, and I tend to agree with Douglas the ruder stall (when you tern it to much to one side is a pain, and the skeg when trimed is more responcive and wont cock as much , the new shape boasts what yous to be referd to in sail making terms as a ''fat hed'' which I did find hard to role, ( a re enter role up job for me ! ) but im also playing with a mid wing , and the change from a big coriebrecan blade to the wing might have been enough to up set things ?
another thing, Im realy liking the new tri laminate fabrick to

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by tommfuller » Tue Oct 18, 2011 7:51 am

So, how long before someone fits a second skeg box, between their feet say, to act as a centreboard...

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Tom.

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by mick m » Tue Oct 18, 2011 9:08 am

tommfuller wrote:So, how long before someone fits a second skeg box, between their feet say, to act as a centreboard...

Cheers,

Tom.
Do you wont a small sail boat that can be paddeld or a sea kayak that can cary a sail ?

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Re: Is it worth tacking upwind with a Flat Earth sail?

Post by chrism » Tue Oct 18, 2011 9:54 am

Here's a sailing canoe

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