Cross-braced misconception

[cloud9 0]

Ok I don’t know if I’m misinformed or if many others are. But here’s the deal; I keep hearing folks talking about canopies like the Stiletto, Crossfire2, Nitron, Cobalt well you get the picture. Now where the confusion comes in is this. I hear it said all the time they are just under the Xbrace performace or a transition canopy to Xbrace. Or it’s ok to fly an elliptical canopy but you’re not ready for a Xbrace yet. At the same wing loading like say a 1.6 what would make the Xbrace canopy any higher performance then say a Crossfire2? The only reason I can see that a cross-braced canopy is a higher performance is because you can load it heavier. I don’t think an FX 119 at a 1.6 wing loading would turn any faster, dive any longer be any more dangerous or perform any better then a Crossfire2 119 with the same wing loading. In fact it may be more forgiving.

But I don’t have any experience on either, so if I’m wrong would someone please tell me how the cross bracing makes a canopy more high performance except that it can be loaded heavier.

I’ve heard it said that until you load a cross brace canopy you wouldn’t see any improvement over a non-Xbraced. In fact it seems to me that many times at lower wing loadings a Xbraced canopy would be more docile then a non-xbraced elliptical.

Any thoughts on this? Is my thinking flawed? I guess I’m just sitting at work on a Saturday and can’t jump so it makes for some strange thinking.

[Yoshi 0]

Preface: I havent jumped crossed braced.

To my understanding the wingloanding will play a major factor in it all.. if you have a fx 119 and cf2 119 the fx will go faster.. it is more of a rigid wing and if you look at the thickness (other pilots correct me if I am wrong) the fx will be thinner from bottom skin to top skin. the fx will dive longer... cf2 will prob turn faster (I dont think cross braced canopies in general turn all that fast compared to the size and wingloand of a similar canopy) harness input with be more sensitive on the fx.... openings will most likely be a handfull more to deal with with the fx... I have been told by my brother that his crossfire2 105 flew slower than an fx 115. although this was loaded 1.9ish or in that range. if you are going to loan a canopy in the mid 1's of wingload it jsut plain wouldnt be worth the money to get a crossbraced and it would most likely be more dangerous as the speed, opening, and dive. I am sure some more posts will be made on this, but I hope I am correct in my assumptions. Anyone out there feel free to correct me


-yoshi

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this space for rent.

[billvon 2,998]

> At the same wing loading like say a 1.6 what would make the Xbrace
>canopy any higher performance then say a Crossfire2?

There are a lot of factors that go into the design of a canopy. Crossbracing really only benefits you if you are at high wingloadings and want the swoop performance; therefore crossbraced canopies are typically designed to be more aggressive. It's not the crossbracing that makes them more dangerous but the more aggressive design.

It's like saying that planes with very high power to weight ratios are more dangerous. The power to weight ratio in and of itself is not inherentlly dangerous, but often such aircraft (pylon racers and the like) are designed more for speed than for safety.

[andy2 0]

don't most cross braced canopies have a longer recovery arc, therefore making it harder to get oneself out of the proverbial "corner" than on an elliptical?

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let my inspiration flow,
in token rhyme suggesting rhythm...

[sundevil777 102]

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don't most cross braced canopies have a longer recovery arc, therefore making it harder to get oneself out of the proverbial "corner" than on an elliptical?

If it is true, it is not because of the crossbracing itself, it would only be true because the overall design is more aggressive.

Crossbracing makes it possible to have a more efficient wing. What else is done with the design is what might make it more "dangerous".

People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

[GroundZero 0]

very good question from very logical thinking... I'll watch these answers for a bit!

Chris

[GroundZero 0]

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therefore crossbraced canopies are typically designed to be more aggressive. It's not the crossbracing that makes them more dangerous but the more aggressive design.

What do you mean when you say X-braced canopies are "the more aggressive design"?

Chris

[sducoach 0]

Cloud9,

At least you are thinking about it. That is more than most do these days, but............

Look at your responses so far,

Jumps canopy
250 Heatwave 150
394 Crossfire 111
2700 Safire 129
1100 PD9 210
5300 Xaos 84

and I'll throw mine in too.

3300 Vengeance 107

You are going to get many opinions here, but very little real information.

Call the manufacturers, all of them, and discuss your questions, concerns, skill level, and desires.

You'll get some marketing from them but all have been very straight forward in the past concerning what you want from a canopy, your skill level (read experience), and what you are flying now (read experience and point of reference concerning performance). Then, make your own best choice.

Blues and be safe.

J.E.

James 4:8

[billvon 2,998]

>What do you mean when you say X-braced canopies are "the more aggressive design"?

It is the more aggressive design of a canopy like, say, the Crossfire that requires more pilot skill, not just the fact that it has crossbraces. (That and Crossfires are typically very heavily loaded.) You could put crossbracing on a Manta and it wouldn't make it harder to land, but then there's not much reason to put crossbracing on a Manta.

[cloud9 0]

Just for information I have no desire at all to go to a cross braced canopy or make any changes in what I'm jumping now. I'm just trying to put information out there and see what information I get back. I think there is a lot of misconception about canopy designs. It could be on my part or others so lets see. But I can see this thread helping many others if we get good respones from experienced folks like we have already seen. Thanks everyone for responding.

[johnny1488 1]

The reason x-braced canopies can do what they do is they stay in the shape thay were meant to be in. If you were to load a conventional canopy at say 3.0 you would lose a lot of lift due to airfoil distortion. The canopy during flight doesnt reatain its origonal shape during inputs (such as flaring). A x-braced canopy is more rigid and stays in its designed shape during flight on high winloadings. As far as characteristics? I think those are built into the design of the canopy itself, ie planform shape, trim, line length, ect. I could be in left field but this is what i've come to understand from my endless canopy info binges. By the way I have 537 jumps and jumps a xfire2 169 loaded at 1.4.

Johnny
--"This ain't no book club, we're all gonna die!"
Mike Rome

[jdfreefly 1]

Seems to be some confusion here. A Crossfire(1 or 2) is not a crossbraced canopy.

The crossbraced canopies I know of :
Icarus FX
Icarus VX
PD Velocity
Percision XAOS

The crossbraced canopies tend to have an angle of attack such that, once put into a dive, they will stay in it until flown out. This makes them ideal canopies for swooping because you can do a much longer diving aproach on your swoop. It also makes them horrible canopies for people learning how to swoop.

Methane Freefly - got stink?

[ianmdrennan 2]

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The crossbraced canopies tend to have an angle of attack such that, once put into a dive, they will stay in it until flown out. This makes them ideal canopies for swooping because you can do a much longer diving aproach on your swoop. It also makes them horrible canopies for people learning how to swoop.

Nope, but I believe their camber is greater than non-x braced. They will however return to their regular decent rate if given enough altitude.

blue skies
Ian

Performance Designs Factory Team

[apoil 0]

The crossbracing gives the canopy more rigidity. It does more than just allow it to be loaded higher. At light wingloadings the crossbracing would be at best a wasted 30% increase in cost, or at worst, might actually be harmful, more prone to collapsing, since higher speed is necessary to maintain pressurization. That last is speculation but it is a bad idea to underload a cross braced.

At wingloadings greater than 1.6 or so, there is a big difference in the way these canopies fly.

They will have roughly the same speed for their wingloading in level flight, but they will dive much harder and be able to pick up much more speed in their long recovery arc.

Also when the flare begins they have the illusion of picking up speed, because as they go from a dive to a plane out, they seem to increase the component of the speed that is parallel to the ground. They just don't slow down when you start to flare them, and they keep going and going and going. So it is unquestionably a master's canopy.

highly loaded 9cell ellipticals have to be flown more specifically to build up speed, and they will swoop long and far. But after putting in your 500-1000 jumps on one, if you try a crossbraced at the same wingloading, you will see that it's a different animal entirely.

So in short, crossbracing is not just some nifty addition to an aggressive design. The crossbracing is part and parcel of that agressive design.

[cloud9 0]

I haven't seen any confusion, everyone seems to know the difference and everyone seems to know that the Crossfire is not cross-braced.

There have been one or two that have said the design is more aggressive but not what makes it so. There have been others that have said it dives longer and has a greater recovery arc but again not why.
Some have said it will swoop farther but I have already conceded that, by saying it can be loaded heavier. Of course I ment that it's more rigid under a load so that's a given. Someone did mention the cord which I didn't think about and that makes some sense as to more speed, but then agian all those closed cells could create more drag.(don't really know)

I'm still thinking that a cross-braced canopy at a lighter wing loading would be more forgiving then a non cross-braced elliptical like the Nitron vs Xoas 21.
When I say lightly on Xbrace I mean 1.6 and under range.

This is very interesting any more thoughts?

[jdfreefly 1]

It seemed like some of the comments that had been made might confuse a newbie into thinking a crossfire is a crossbraced canopy. I have heard people refer to it as a crossbraced canopy before. Most likely due to the name. Also, the front looks crossbraced due to the partialy closed nose.

Just wanted to avoid confusion.

Methane Freefly - got stink?

[jeremyneas 0]

One of the main points to landing any cross braced design canopy is the tail deflection. On 21 celled it's around 11.25% and 27 celled around 8.7%. These compared to conventional 9 celled canopies that deflect around 20%.

This factor contributes to longer swoops becuase of the less air resistance while landing.

This also means that if you find yourself too low, or making a foolish mistake, the less deflection means that the canopy will not pull you out of a bad situation as easily, hence the greater skill required to fly them.

The cross bracing that leads to this more stable design, also allows the top skin and bottom skin to be closer together, making a 'thinner' canopy than conventionals, thus creating less wind resistance.

There are other factors, but these tend to make or break.

In the end though, it all comes down to the canopy pilot. Weaker pilots will downsize quickly to compensate for the fact they can not fully use the potential of their current canopy. Strong pilots can swoop a spectre 170 halfway down a football field (because they can!).

These factory teams that use very small cross braced canopies in a variety of situations have mastered technique and equipment, and are the leading people to ask these questions to, along with those designing them.

To just grab the advice of the local blowhole is (relitavely) foolish becuase it is your life in the end.

J.Neas

[jeremyneas 0]

Just to add on. Those small tail deflections on a lightly wingloaded canopy, would cause poor (possibly breaking) landings in a slow speed situation.

And yes, i'm a local blowhole, tread lightly.

J.Neas

[tictoc 0]

"In the end though, it all comes down to the canopy pilot. Weaker pilots will downsize quickly to compensate for the fact they can not fully use the potential of their current canopy. Strong pilots can swoop a spectre 170 halfway down a football field (because they can!)."

I like this statment. I donn't think anyone could say it better.

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Some one must go to the edge for others to be able to find it. But if you go be sure you can make it back.

[crazy 0]

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if you try a crossbraced at the same wingloading, you will see that it's a different animal entirely.

Did you try a x-braced size 98 recently? I'm wondering if there is that much difference with the blade.
I tried a VX80 recently (i usually fly a nitro 88). Apart from the much shorter toggle stroke, the VX80 didn't give me such a thrill. It was a bit faster (smaller size + smaller angle of attack), but it gives much more room for error. Way easier to land (better bottom end flare), and extremely safe to dig out of the corner (longer natural recovery arc and shorter minimal recovery arc, less risk of a dynamic stall). Landing after a half brake approach is even easier on the VX than on the nitro. On the other hand, with its extra long lines, the VX feels sluggish.
So, yes, a completely different animal, obviously higher performances... but in the same line as cloud9's comments, i'm still wondering why so many people think that x-braced are the next step after an highly loaded normal 9 cell. If that was the case, a x-brace pilot would be comfortable under a same size (or smaller) stiletto, which is hardly the case.

--
Come
Skydive Asia

[Hooknswoop 19]

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tail deflection

Do you mean cell distortion or bulge distortion?

The 8.75%, 11.5% and 20 % numbers come straight off Icarus's VX advertisement.

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This factor contributes to longer swoops becuase of the less air resistance while landing.

Longer swoops because the crossbracing doesn't allow the non load bearing ribs to rise, shrinking the canopy, end cell to end cell. You land more square feet.

Hook

[jeremyneas 0]

case in pt, tkx derika

J.Neas

[waltappel 1]

I think the description of "aggressive design" refers to the tradeoff of canopy stability vs. maneuverability. For example, elliptical canopies seem to be quite a bit more sensitive to harness input than rectangular canopies, so they are less stable, but they can turn quite dramatically.

[apoil 0]

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Some have said it will swoop farther but I have already conceded that, by saying it can be loaded heavier.

heavier load does not equal longer swoop.

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Someone did mention the cord which I didn't think about and that makes some sense as to more speed, but then agian all those closed cells could create more drag.(don't really know)

if you look at these canopies, the wing itself is not very thick (top to bottom distance). This is not "chord". It is "airfoil thickness" This serves to reduce drag among other things.

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I'm still thinking that a cross-braced canopy at a lighter wing loading would be more forgiving then a non cross-braced elliptical like the Nitron vs Xoas 21.

You aren't thinking so much as speculating. You are only taking into account a few points when you make this assumption that cross bracing might make lighter wingloadings more forgiving.

The Nitron is a very bad example, because in many ways it is one of the most forgiving ellipticals out there. It is designed to have ultra high controllability in it's slow flight modes, and a very very powerful flare. This can get you out of a lot of trouble. The Nitron may well be more forgiving than say, a sabre2 at a given wingloading. But it's hard to say.

Anyway, the fact is, that no manufacturers have considered crossbracing as a "Safety feature".

I think it would be far too expensive to include cross bracing on lower performing wings. And it is not recommended to take the existing crossbraced wings much lower than 1.6. This is from the manufacutrers who designed and tested them.

As an alternative, Brian Germain's airlocks do actually provide some of the same benefits as crossbracing along the leading edge. This is because the load is distributed along the fabric of the airlock.
Brian does consider airlocks to be a safety feature and he does recommend them at light and moderate loadings on the Lotus and Samurai.