Ram airs crash at New Zealand National Titles

[mickpilch]

Yeah, I really don't see this battle thing, foils, leis we were all out together on Sat.

Sun was out, it was breezy everyone havin a ball, I'm no rocket scientist (Lei rider & all ) I couldn't tell you shit about profiles & dynamics, I just get off on having a good session with my buds, maybe a pint or two after, discussing 'heroic moves' pulled.

Point is, on the beach, where it matters there's none of this shit, live & let live we all help each other - regardless of 'creed'.

We're all passionate about OUR sport, sometimes we get carried away - nothing wrong with a bit of piss taking, f*** its the norm, but stay focused on the primary issue: you gotta love it!!

[Guest]

- The most important aerodynamic aspect of any kite, after sheer size and aspect ratio, is the LUFF CURVE (profile depth).

The luff curve is the curve of the leading edge, not the profile or foil shape.

- Rams are unable to handle the shear stresses and turbulence at the very edge of the window because they lack a semi-rigid structure. This is why inflatables like the X3 are superior to rams. They sit closer to the edge of
the window,

Some foils sit just as high in the window, if not higher. They tend to have stability issues. Foil zealots will usually blame the riders skills.

enabling flying off the front lines, low bar pressure, extreme penetration to the top of the window (enabling very high jumps) etc.

The Rhino 2 sits further back with good solid bar pressure and outjumps or at least matches any other kite currently on the market. Kites that fly too far to the edge of the window suffer at the low end and hang time. Its definitely not black and white.

- Because large rams (eg Warrior 16.5) have a HUGE "D" coefficient compared to inflatables, they are unable to generate the sudden upward power spikes.

Nope. They don't jump worth beans because they turn too slow and accelerate poorly out of a turn. What do you think is the mass of all that air inside a big foil? It has neutral boyancy in air but it all needs to be accelerated regardless.

Glad I could sort this out for ya.[/quote]

[Guest]

1. fact one, i'll outpoint any lei rider in any wind condition for upwind ability riding a psycho, lei's do not penetrate as far upwind as foils and are less effeicient designs primarily due to their tiny projected area....

It's supremely easy to outpoint 99% of all riders (foil or tube) because they just don't give a crap whether they are getting max vmg. Unless you race other racers it's pointless to make this claim. And if you do win, congratulate yourself on you skills first and choice of equipment second. Anyways, 99% of us don't care.

2. my roughly put together demo titan quite happily outpoints any lei from even a static position on the beach,

Completely irrelevant, how a kite flies unloaded.

do you seriously expect people to believe that a static wing system with only pivot from the leading edge attachments points, such as your x3 can be more efficient than a soft foil that has a totally adjustable foil profile. have you even seen the psycho, they have a fully cambered and adjustable profile, not just angle of attack, they are a reflex design, not just a pivoting sheet like an lei.

Putting reflex in your profile adds stability and decreases performance. When you deform your profile you are introducing canopy distortions, increasing drag. It's not a win/win situtation. In order to get a lot of aoa adjustment out of a foil profile, you need heaps of reflex. To get performance you want less reflex. Pick your poison.

3. leis more stable at the edge of the window, thye aren't more stable not the x2 i used last week, with the titan, or the mach 1 i used all saturday, they were just the same. if youd tried a new set of foils and had the skill to handle them, you might find this out.

The x2 has top notch stablility. It far outperforms the psycho on this criteria.

just as big foils turn slowly so large leis are ridiculously heavy and impossible to relaunch, the 16 warriro is equaivilanet in pull to a 22m lei, so lets compare like with like.

You can fly either one in too little wind to relaunch. One of them you can jump, the other is cruising only. Whatever rings your bell.

[Guest]

i find it funny that people are letting themselves get drawn into this.

The ultimate irony

bottom line, leis are just simpler more basic kites, with less performance and less adjustability, simple kites for simple people....

Now that's the dumbest thing I've read in a while.
You and pmu deserve each other.

[KiteGlider]

The luff curve is the curve of the leading edge, not the profile or foil shape.

Having limited sailboat experience, I was interested in learning more about "luff curve". This what I found on a web search.

Relating to sails, boat and windsurfer, luff curve is the depth or belly of the sail. The sail cloth/material is cut to allow excess to give profile or "depth".

So PMU is saying that the LEI is a fat belly sail anchored with 2 or 4 lines.

I had some of the best times in my life flying my fat belly sail anchored to a control bar with 4 lines.

I do like the big foils for light wind.

[sq225917]

max air.

i'll happily take all that and lie down from you. becasue you know exactly what you are talking about and not proffering twisted rhetoric to make a point, obviously my responses to pump me up are aimed at pump me up and his type of empty post, fire with fire so to speak..

my own real actual viewpoint on the whole thing is thus.

ride what you want to ride, what works for you. leis are better comp kites, but generally due to their relaunch something from flysurfer is probably a better cruising kite as you say.

kites like the psycho are balls out performance kites in the vein of the x10 and shouldn't considered with other offerings from flysurfer, i don't beleive that they will ever jump as high as an lei due to having greater flat surface area and lower flying speeds.

but i think we can probably agree that they exceed leis in hangtime from same height jumps, due to that very surface area...

its as simple as that its so personal, hence my post on upwind ability, an area where i know i'm bettter than most as i ride in the most marginal of winds and really know how to milk the power in any conditions.


thanks for the heads up fella its nice to see someone with a reasoned viewpoint.




AND YES, THE I CANT BELIEVE YOU GUYS..... was irony.....

[Guest]

The luff curve is the curve of the leading edge, not the profile or foil shape.

Having limited sailboat experience, I was interested in learning more about "luff curve". This what I found on a web search.

Relating to sails, boat and windsurfer, luff curve is the depth or belly of the sail. The sail cloth/material is cut to allow excess to give profile or "depth".

Could you give us a link?
I have never heared of the draft (depth/belly) of a sail refered to as luff curve. Any link I can find explains the luff curve as the curve of the luff (leading edge). When you match a curved luff sail to a straight mast, you introduce draft into the sail. The term "luff curve" refers to the leading edge!

[sq225917]

max air, i like you more and more with every post...

if you check you'll find i never mentioned that the psycho was stable, its way not, thats why its a good performer otherwise.


keep up the good posts..

[KiteGlider]

Thanks, Max Air.
Still reading up.

mast deformations possible : luff curve, rotation, rake and inclination. -

So the amount of luff curve being one of the mast deformation factors that introduces dept or foil profile into the sail.

If related to the LEI, then we're talking about a 180 deg luff curve?
The curve is also on a different axis than used in sail design.

Taken out of context from: http://www.lo0.com/fireball/readings/firezone-a10.html

To understand mast tuning one must know a little about how a sail is designed and what gives it its shape. Seam taper and luff curve are the two main components to sailshape and depth. Seam taper (also known as broadseaming) is the depth built into the sail. Seam taper has a percentage depth (percentage of chord length), a maximum draft position source of the shape you see in your main when you are sailing. When you put a positive luff curve on a straight mast the extra cloth (beyond the straight luff) is cloth added to the depth of the main. Most of added shape appears in the luff. How much luff curve is the question most often asked by sailmakers.

Luff curve seems specific to sail design. When talking LEI profile shape IMO we're considering geometry in terms of air-foil design.

[sq225917]

lei might have been marketted by windsurf companies but it has more to do with pargliding and fixed wing theory than sailing.

perhaps pump me up would like us all to buy dinghys.