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are accurancy landings easier with some wind versus no-wind?

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Just curious - I'm still trying to consistantly land in the 25m radius circle & getting a bit better - I'm kind of finding that the days where there are low-medium wind are a bit easier than the no wind days. Would kind of make sense based on the smaller angle you glide in at on a no-wind day perhaps?

Am I correct here? Is this what others/experienced canopy flyers find too?
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Just curious - I'm still trying to consistantly land in the 25m radius circle & getting a bit better - I'm kind of finding that the days where there are low-medium wind are a bit easier than the no wind days.



Yup.

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Would kind of make sense based on the smaller angle you glide in at on a no-wind day perhaps?



Classic accuracy canopies and some other traditional seven cell designs have a range of glide ratios from about 2.2:1 in full-flight to straight down in a full-sink with 2/3 brakes providing a 1:1 descent that still produces a soft landing with a full flare. The canonical classic accuracy final approach tries for a 1:1 glide path aimed just past the target and terminates with a sink over the top (preferably onto a soft surface like a tuffet or pea gravel so you can sink from higher up). You make the glide path steeper or flatter to accommodate where your final approach started and finish it off where ever you need.

Modern skydiving canopies have a flatter glide in full flight, get flatter still with some brakes, and pretty much stay there until just short of stalling. Instead of controlling where you land without wind brakes just determine how fast you get there. Contemporary skydiving wing loadings (about 0.7 is ideal for classic accuracy) wouldn't produce enough aerodynamic drag after they stop flying to land you softly after a sustained sink even if that was easy to get to. So accuracy with them is largely about turning onto final approach at the right spot + altitude.

Some wind gives you control over the steepness of your approach and makes modern canopies act more like accuracy canopies.

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Am I correct here? Is this what others/experienced canopy flyers find too?



That's how it works.

With contemporary canopies, no wind, and nothing bad happening when you miss (flying into a boulder/tree/stadium) an accelerated approach followed by popping the canopy up, stalling, and sinking when you get where you're going works well. OTOH, with extra speed getting that wrong makes it easier to break things.

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Yes, it is easier to control one`s glide angle towards a target area when there's some wind.

Part of it is just a matter of angles, a shallow vs. steep approach:

If you have a really shallow glide angle in low wind, mis-estimating your approach angle by a small amount can leave you sailing well past the target. But if you are descending more steeply, the same size error in flight path will result in less change in where one touches down.

The second part of it is how much difference brakes will make in your glide angle, in headwind vs. no wind:

Lets say you have a canopy that moves 25 mph horizontally, and you can easily add some brakes to slow it to 20, with a similar rate of descent. Glide ratio starts at 3:1. (I'm oversimplifying in that there can be all sorts of different speeds and descent rates depending on the canopy, but this one example isn't totally unrealistic.)

In no wind, changing to 20 mph from 25, at a similar descent rate, will only change your glide angle over the ground a moderate amount -- a 22.6 degree descent angle instead of 18.4. Just about 4 degrees difference.

Then if there`s a lot of wind, say 15 mph, slowing the canopy by 5 mph will give a 5 mph ground speed instead of 10. Now for the same descent rate, the descent angle will go from 39.8 degrees to 59 degrees -- about a 19 degree difference.

So you can see that small changes in your speed will have a greater effect on the flight path over the ground, when there isn`t as much ground speed to begin with.

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does anyone remember DOWNwind accuracy??????;)

that was how it was done,, Before RamAirs...

in that case no wind was better than some wind...

....upwind accuracy is MUCH nicer.. imho

" so there i was,, i was holding brakes, sinking it in,,, and i STILL came up short..." :o:S what happened???

jt

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Instead of controlling where you land without wind brakes just determine how fast you get there.



Not really. The same concept applies and will allow me to land a modern canopy pretty much like an accuracy canopy. The difference between full and braked flight is less on a no wind day, but on a ~10 MPH day I can land a modern canopy pretty much like a traditional accuracy approach to include the sink straight down from 8-10 feet.

Everything else is pretty much correct, but even a modern canopy in half brakes is going to shorten the glide path.
"No free man shall ever be debarred the use of arms." -- Thomas Jefferson, Thomas Jefferson Papers, 334

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Instead of controlling where you land without wind brakes just determine how fast you get there.



Not really. The same concept applies and will allow me to land a modern canopy pretty much like an accuracy canopy. The difference between full and braked flight is less on a no wind day, but on a ~10 MPH day I can land a modern canopy pretty much like a traditional accuracy approach to include the sink straight down from 8-10 feet.



With a 10 MPH head wind. The accuracy canopy will do it with zero wind or a slight tailwind if you can tolerate a less than vertical sink.

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Everything else is pretty much correct, but even a modern canopy in half brakes is going to shorten the glide path.



Only with a head wind.

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The point is you said"
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Instead of controlling where you land without wind brakes just determine how fast you get there.



And it is false.

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Only with a head wind.



False. It is a BIGGER change, but your logic that it does not work without a head wind is false... The canopy does not know if there is a headwind or not and does not have a switch that changes the functions of a control group based on the position of that imaginary switch.

Does head wind make the relation of canopy speed and ground speed more observable? YES, but it does not change the physics of the universe.
"No free man shall ever be debarred the use of arms." -- Thomas Jefferson, Thomas Jefferson Papers, 334

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>The canopy does not know if there is a headwind or not and does not have a switch
>that changes the functions of a control group based on the position of that imaginary
>switch.

Correct. But since you do not want to land on a certain place in the air, and instead want to land on a certain place on the ground, the headwind does matter a great deal when it comes to accuracy.

>but even a modern canopy in half brakes is going to shorten the glide path.

Nope. On a modern canopy, if you add brakes in no wind, you're going to extend your glide over the ground. (Try it on a no-wind day.) You have to be very deep in brakes to get a steeper glide, again in no-wind.

Now add 10mph of headwind and adding brakes will shorten your glide with respect to the ground. (Of course in both cases the canopy will follow exactly the same path in the air, with respect to the air mass.)

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Correct. But since you do not want to land on a certain place in the air, and instead want to land on a certain place on the ground, the headwind does matter a great deal when it comes to accuracy.



Yes, but it does not change the fact that brakes will shorten your glide. The only difference is that higher winds will show a greater difference.

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Nope. On a modern canopy, if you add brakes in no wind, you're going to extend your glide over the ground. (Try it on a no-wind day.) You have to be very deep in brakes to get a steeper glide, again in no-wind.



I have done it and I disagree with your claim. I have qualified for a PRO rating on a Star Trac I, Sharp Chutter, Stiletto 107 and V96.

The canopy does not have different settings for no wind and wind. The same input brings the same result. The only difference is that in a no wind day the change will be harder to detect.

You are trying to claim that brakes only slow down the canopy when there is a headwind wind.... The very act of flaring proves that is not correct. It makes a BIGGER difference in higher winds, but it still slows a canopy down in zero winds.

Same input yields the SAME result of a shorter glide.... It may be so small to not even notice on a no wind day, but it will not suddenly change physics and extend the glide in one situation and shorten it in another.

And as you asked for me to do it.... I have done it on several canopies from xbraced 88's to 366 tandem mains.
"No free man shall ever be debarred the use of arms." -- Thomas Jefferson, Thomas Jefferson Papers, 334

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Thanks for all the advise/info guys. So I'm gathering if I turn onto final on a no wind day and need to adjust (large canopy) some brakes will help adjust the approach but it may not be that noticeable.

Actually on a non-wind approach (shallow angle) will the "accuracy trick" work well for judging where you're going to land? I think I've got then sense of it on a low-medium wind day, but not so much on a no-wind day.
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Actually on a non-wind approach (shallow angle) will the "accuracy trick" work well for judging where you're going to land? I think I've got then sense of it on a low-medium wind day, but not so much on a no-wind day.



The "accuracy trick" works in varying winds, yes.

The only difference in using the accuracy trick on no wind vs moderate wind days is how to account for your flare. On a no wind day if you're going right for a target in full flight and then flare, you will touch down a bit past your target. On a moderate/high wind day, if you're going right for a target in full flight and then flare, you will touch down a bit short of your target. You're not going to be off by 10s of meters or anything, but if you are really looking to dial things in you should consider how strong the winds are when choosing your "accuracy trick point"

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thanks champu - thats seems to align with what I've been noticing - so on the low-wind days I should aim lower in the circle then.... a recent jump in no-wind I was aligned perfectly, then in the last 5m vertical as I flared just kept going and landed 1m outside the circle....I was saying nooooo to myself as I just missed it :)

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