Objective - 25 knots speed, glide, power carves with optimum control downwind in winds 15-35 knots and 2m swells (and waves).

Tested the HA wings below - all had excessive lift which I'm used to dealing with, but also roll instability pushing 20 knots in swell.
Tried a few different tails which didn't make much difference. Always max out at about 22 knots downwind regardless of wing size.

So I thought small HA wings (600-700cm2) were the problem and I needed to go back to medium aspect similar to my Simmer 920cm2 which has the same excessive lift at times but doesn't have roll instability issues.
I was guessing around 800cm2 MA would be the sweet spot.

But I tried an even smaller HA wing a few days ago (Simmer 550cm2) in 20-25 knots, 1.5m swells - the excessive lift has gone as expected, still a little roll instability (perhaps aluminum mast flex) but now I think I could learn to deal with a little HA roll instability if I'm not having to deal with excessive lift as well, to unlock the speed potential.
That thing is crazy fun
Probably have to use the bigger W114 board to get up on foil easier.
But I'm thinking worth it for next-level glide down swells
So I've ordered the Axis ART 699 (556cm2) as I've already built a Phantasm adapter.

Welcome anyone's thoughts/experiences, I don't have many answers.
Lots of things seem contradictory/counterintuitive.


Phantasm PTM 825 (758cm2), Axis ART 799 (730cm2), Phantasm PTM 730 (656cm2), Simmer 550cm2, Simmer 720cm2
Pix aren't to scale, 550 is a lot smaller.

Good points, thanks
The ART 799 definitely had heaps of lift and not especially fast.
But I'm hoping the smaller 699 will have just enough lift and thinner/faster.
Not so worried about breach recovery as I use the 103 mast so it's not a major issue.

I like the AXIS HPS wings but the problem is the smaller wings have low aspect ratio and for this experiment I want to max out on HA glide/speed.
I'm sure they'd be nice and controllable though.

I ride the HPS 700 on a 105 axis aluminum mast with a 370 tail it is a fun setup but have yet to try in open ocean conditions and yes it has it's limits usually pair it with a 4.1 or 3.4 sail and the wizard 114. It does have a good amount of glide and craves a nice turn. Would love to see how you make the adapter for the phantasm fuse as I have only used mine with the 730 front 103w mast combo.

Foil wings are lifting surfaces. The more the speed, the more the lift. Every single wing in existence will develop "excessive" lift as you accelerate down a wave face. As you increase speed down a wave face the sail mast base pressure actually decreases, making this even more of an issue.

As you are now searching, the whole goal is to get that magic balance of lift and speed in changing conditions. Once you get close, what I notice is that people are experimenting with stab shims to fine tune this.

That's the nice thing about winging or kiting on wave faces. Just step a little more forward to counterract the increased lift. For the wingers it becomes second nature. No sail mbp to worry about.

I wish I could give you some WWF feedback on the Phantasm G800 JJ but since the last Hurricane it has screwed everything up on the sand bars and the shore break is insane at most beaches.

I have been winging more because I love jumping off little faces, and we have had only one good North wind this winter and that day there was no swell for any swell riding, it's so frustrating

We have wind forecasted Friday but its West which means foiling on the Intercoastal's... it's an impossible direction on the oceanside....fingers crossed I can test it soon and let you know.

This was last week at the best foil wave spot on the G800, again better for boosts but no real swell to ride in!!

JJ, take him up on the Go foil offer! I would love to hear your comments about that gear after everything else you have tried.

I'm on the Naish Mach 1 900sqcm for high speed swell riding. These are solid carbon with very little flex and provide a very solid feel and good glide. I tried the higher aspect thin wings but they were too twitchy when throwing them into turns. I'm 80kgs, tried the 1100 Mach1 but too much lift.

Hey JJ, I am not sure I am qualified to help but I have a couple thoughts on maximizing speed and stability in high winds on a bigger wave/swell

I have been using the SAB 945 (1300 cm2)in all types of wind and waves because it makes any wave feel bigger than it is. I have come straight down (I prefer to ride waves down/up the line) some pretty big waves with very little increase in lift although it dose max out in speed. My experience is that thin flat HA Wings and Stabilizers produce the best glide and remain loose on the wave. And Fuselage length will effect turning radius. Of course you want a thin stiff mast for control. Which is were I sounds like you're heading.

jdfoils said..

CoreAS said..
I wish I could give you some WWF feedback on the Phantasm G800 JJ but since the last Hurricane it has screwed everything up on the sand bars and the shore break is insane at most beaches.

I have been winging more because I love jumping off little faces, and we have had only one good North wind this winter and that day there was no swell for any swell riding, it's so frustrating

We have wind forecasted Friday but its West which means foiling on the Intercoastal's... it's an impossible direction on the oceanside....fingers crossed I can test it soon and let you know.

This was last week at the best foil wave spot on the G800, again better for boosts but no real swell to ride in!!

If he is looking for something super stable in roll, then the g800 is not it. The g800 is super free in roll and easier to carve than any foil i have tried, including many on his list.

Having said that, for me the g800 is a great foil for high wind and swell riding. Mostly that is because it is so free in roll which helps with continuously flowing the carve radius.

Cheers Dean and JD

The G800 looks the goods - very similar in outline/area to my 926 wing I cut down 18 months ago, but without the joining lumps
I should get on it again, haven't been using it since adapting the Simmer 920cm2.

For 25 knots speed downwind in swell I think I need to find a controllable small HA wing probably under 600cm2 and 8+ aspect ratio.
Such a pain that the brands have wildly different wing to fuse connections.


G800

Axis ART 699 - first couple of sessions on the ocean in 20-25 knots and on the river in 15-20, lift for powered-up sailing is perfect but still loose in roll and also in yaw.
Was going to add winglets to the 699 but persuaded (by a QANTAS pilot ) to try a vertical rear wing and make use of the leverage/moment of the relatively long fuse.

One session adding the fin below, big improvement, had some epic downwinders, yaw and some roll mostly stabilized.
A good start, I'll see how it feels after a few more sessions.

Glide down swells is beyond epic

Taking a super loose, low drag foil then modifying it to have more drag and be more directional seems counter productive.

Grantmac said..
Taking a super loose, low drag foil then modifying it to have more drag and be more directional seems counter productive.

I agree - it is a little.

But all HA wings (above 9:1, 550cm2 to 1100cm2) I've tried are directionally unstable with a wavesail in swell, at least for me.
If we had any young ripper windfoilers they might not have the same issue.

Riding swells downwind at over 20 knots with minimal drag is so addictive I'll keep chasing a good solution.

Qantas Mike has given me a name for my malady - Dutch Roll.
The vertical fin helped a lot with the ART 699 (556cm2). I couldn't feel any difference with the Simmer 920cm2 MA foil. I guess chord adds directional stability.

Dutch Roll at Dutchies

Dihedral is a strange thing in foils. Logically all our foils with anhedral should be extremely unstable in roll, but it seems to work opposite in a foil. But adding anhedral to the tips makes tip breaches far worse.

Most foils are going to a fair amount of anhedral in the center that flattens or even goes into dihedral at the tips. This makes for good initial stability but the ability to pull the tips out.

Just my observations anyway.

The idea of a HA wing for down winding swell seemed counter to what I want if you asked me, but got out today and tried it on my AFS S670 cm2 wing, it was a blast!, very fast, could shoot down the swell troughs. Wind was in the 15-18 knot range. The long down wind runs un-hooked were my favorite part of the day.

azymuth said..

jdfoils said..
The solution th Dutch roll is at add dihedral to the main wing, coupling yaw to roll

Thanks, agree - my next move if roll is still an issue is to add dihedral winglets to a spare 400 Phantasm rear wing.
Easier than adding them to the front wing and I'm hoping works similarly.

Hey Azymuth, trusting you are noticing a difference in roll characteristics with the changes you are making. Just wondering what effect different masts may have on roll. Only because it does have a lot of surface area in the same plane. Just trying to help
Have a great day

thedoor said..
After seeing greg glazier sail in mexico, I am starting to wonder if other factors are more important to speed. He was going about 3-5 knots faster than me on all points of sail and he was handling 2m troughs no problem. this trip he was on the phantasm G800 and the 125cm mast. I didn't get the impression that the G800 was responsible for his speed.

I reckon the G800 mid aspect wing (similar to my cutdown 926 wing) is nice and controllable in bigger swells.
The 125 mast probably helps too - but not practicable for us because of all the reefs. Also it would have more drag and be slower.