Top speed of a Moses 633 SUP wing combo (the Onda)

[Foil]

[quote=Peter_Frank post_
Whereas other higher AR wings with thin low drag profiles, will stall very suddenly and very difficult to recover.

It is the classic "performance/agility/ease" tradeoff
[/quote]

Brilliant I have a new set of Moses race wings, I have not used them as yet, holiday in less than 2 weeks so will have a go in good winds with my gps watch on to see just how much faster they are over my standard freeride wings,I bet they mess up my gybes in fine style

[Foil]

[quote=Peter_Frank post_
Whereas other higher AR wings with thin low drag profiles, will stall very suddenly and very difficult to recover.

It is the classic "performance/agility/ease" tradeoff

Brilliant I have a new set of Moses race wings, I have not used them as yet,
holiday in less than 2 weeks so will use them there in warm waters and good winds with my gps watch on to see just how much faster they are over my standard freeride wings,
I bet they mess up my gybes in fine style
[/quote]

[grigorib]

slowboat is spot on, with a kite the stall speed can not be "claimed" - makes no sense at all.
..

PF

Kite is only a propulsion. Stall speed is not measured for a wing but for an aircraft and it’s quite defined number.

To realize you can take a 558 wing at your weight and any choice of kite and I’ll do the same with 633 and let’s see who can go slower on a straight cross-wind line not touching board on water.

[Sandras]

Kite is also lifting you up reducing the weight the foil has to support!!

In Fluid mechanics there is no stall speed, there is only stall angle of attack.

[gmb13]

Stall is not a function of speed.
Stall happens at a certain angle of attack.

What is meant above is that at that speed, you need such a high angle of attack to support your weight (minus the kite lift) that this angle of attack is critical - stalls.

I assume that gunnar said 82kg meaning no kite support, especially considering it's a SUP wing!

Yes. That is exactly how I measure the stall speed.

[TomW]

I thought it was variable amount of lift at variable AoA. Then at certain AoA lift decreases, a stall. Some wing designs, thus curve is falling drastically and deep, like cliff. Other wings the curve is more like a hill.
The cliff curve is difficult to recover from, the hill is easier.

[Peter_Frank]

I thought it was variable amount of lift at variable AoA. Then at certain AoA lift decreases, a stall. Some wing designs, thus curve is falling drastically and deep, like cliff. Other wings the curve is more like a hill.
The cliff curve is difficult to recover from, the hill is easier.

Very true.

Eventhough on the "stalled" side, any wing will behave quite erratic meaning difficult to predict what will happen.
Huge difference on dynamic stall as you can smoothly get some wings to a high stall angle, but if too rapid they will drop.

Also, the SPECIFIC stall angle of attack is of no use for comparison at all.

The high lift wings often stall at a lower AOA than the faster ones, because they have a lot of lift at zero angle of attack, as opposed to more flat/fast wings, which often outweighs the surplus lift.

Generally though, very low drag wings will have a steep polar curve, both before and after the stall point.

And thicker more blunt, high drag wings, will have a gentle hill instead, so be way easier in terms of the stall - meaning you can push too much and it still dont stall, as opposed to the faster wing that will just drop you.

What happens in reality though, is that when a beginner push too much with the rear foot (or ride too slow) without having the wing fly up, it goes past the stall point, but it still has lots of lift even when way over the "ideal" max lift point, so it will not stall immediately.
But because the drag will increase HUGELY now, riding speed goes down, and you drop anyways, because lift is squared with riding speed.
So apart from muscle memory kangarooing because one can not control pitch, you also see this stall kangarooing we know so well from the learning phase.

Lower aspect wings can be pushed to a higher AOA without stalling, because the "overall" polar gets even more blunt (hill and not steep).
This is why they stall so gently and can be recovered, especially because they often have more lifting profiles, so used for beginners, or wave wings where these characteristics are a must eventhough for two different reasons.

As opposed to race wings, high AR and faster profile, so the stall will be violent, compared.
But doesnt mean a thing for racing, so perfect

PF

[grigorib]

Peter, do you tend to associate larger/slower wings with beginner riders and pushing the race wings as a pinnacle of foil development for “experienced” riders?
Because nether Gunnar Biniasch nor Greg Drexler are beginners and they can ride either but both like large wings for freeride.
Ability to go slow easily is so obvious for large freeride wings that it makes them an natural choice for non-racers and I don’t think it’s correct to define the choice as “beginner vs. racer” because not everyone races, not everyone is trying to measure and compete in so called proficiency. As long as one’s riding is a pleasure to watch....

[cwood]

Peter, do you tend to associate larger/slower wings with beginner riders and pushing the race wings as a pinnacle of foil development for “experienced” riders?
Because nether Gunnar Biniasch nor Greg Drexler are beginners and they can ride either but both like large wings for freeride.
Ability to go slow easily is so obvious for large freeride wings that it makes them an natural choice for non-racers and I don’t think it’s correct to define the choice as “beginner vs. racer” because not everyone races, not everyone is trying to measure and compete in so called proficiency. As long as one’s riding is a pleasure to watch....

This is a great point! It's like in downhill skiing....race skis are not all that pleasant for all but the few recreational skiers who really want that edgy feel. For everyone else, even high performance non racers, there are much better all around choices for free skiing. Forcing yourself to ride race skis all the time is kidding oneself. The only thing I think we are still exploring on the race style foils is whether speed and high AR wings give us better boosting performance. Findings so far are yes but I am keen to try the 633.

[Pedro Marcos]

Peter, do you tend to associate larger/slower wings with beginner riders and pushing the race wings as a pinnacle of foil development for “experienced” riders?
Because nether Gunnar Biniasch nor Greg Drexler are beginners and they can ride either but both like large wings for freeride.
Ability to go slow easily is so obvious for large freeride wings that it makes them an natural choice for non-racers and I don’t think it’s correct to define the choice as “beginner vs. racer” because not everyone races, not everyone is trying to measure and compete in so called proficiency. As long as one’s riding is a pleasure to watch....

Well large/slower wings can be ridden by anyone: beginner, intermediate and advanced but race wings can only be ridden properly by advanced riders. Speed also means more risk. Because some advanced riders can have fun on "beginners" wings it doesnt mean those are not "beginner" anymore