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e.a.hernandez

flaring past the stall

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I have seen couple of instances where one jumper tells another (usually a rookie) to flare all the way down. This advice is usually provided without consideration about the stall point on that canopy. I can see how this advice mostly applies to very low jump # skydiver that jumps big >220 canopies set with toggle settings so low that stall point is not reachable or very hard to reach. However, as you start jumping your own gear or for that matter jump any canopy the jumper should find the stall point and not flare past the stall...flaring past the stall point will stall the canopy and specially if the flare is performed by mistake a little higher than usual could cause some hurting or bone breaking. I would like to hear other opinions on this. Are there any instances where it makes sense to flare past the stall point? Should you set the toggles so you can't reach the stall point?

Regards,

Erick

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Unless they're taking a wrap with the brake lines I don't see any harm in telling someone to "flare all the way down" which just means "finish the flare" in my mind... not slam down the toggles to the point where you're landing on your back...

Have you tried to stall a modern canopy? And by that I mean until it bow-ties behind you and depressurizes? It's not really something you can do with a simple stroke of the toggles.

At this point I would just assign this book as homework and call it a day:http://www.bigairsportz.com/publishing.php#parachute
NSCR-2376, SCR-15080

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Normally most new jumpers flare too high and then stall their canopy landing hard. I am somewhat confused because I don't understand the context of this otherwise.

Normally for me I've flared my canopy into a stall and my feet are either running or I am sliding into third base at this point. :P

I'm thinking it means fly your canopy for all it's worth until you've actually landed and not before 20 feet above the ground.... a mistake many newbies make by fearing the ground, their canopy and their judgement of their landing...

I may be mistaken but others can always correct me.

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>Are there any instances where it makes sense to flare past the stall point?

When your feet are on the ground and you have a bit of forward speed left. Generally bottoming out the toggles gives you a bit more drag to slow you down, although by that point you are mostly slowing down via friction between your feet and the ground.

In the air before your feet touch - generally not, unless you have to stop the canopy hard to avoid a larger problem (like you're about to hit an airplane.) In such cases turning works better, but a stall might slow you down faster than a normal flare will.

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The big-ass canopy I started on wouldn't really flare even if I punched it all the way down. It wasn't until I downsized two levels that I even realized the canopy was supposed to do something when you did that [:/]

So there we run into a problem; the advice in my case was kind of appropriate if I wanted to get any sort of flare out of the canopy, but it's one of those "You can't just do that without knowing what you're doing" kinds of things. Once I downsized a better sized canopy for me, that advice was no longer appropriate. Fortunately I got in a beginner-level canopy class before I got my A license and started to realize that about the time I needed to start to realize that.

Better advice, for me anyway, would have been "Commit to doing a PLF on every landing." Unfortunately hindsight is 20/20. You can't really tell which students are going to to be terrible at landing until they're out of the program and no one's paying attention to them anymore. But I got my feet on the ground every time without too many explosions. Except that ONE time when I forgot to flare until after my feet hit the ground. Dunno what I was thinking there. I'm kind of surprised I walked... well... limped... away from that one. You know I never did THAT again, though! That was those big-ass canopies, though, I guess flaring them actually DID do a little something!
I'm trying to teach myself how to set things on fire with my mind. Hey... is it hot in here?

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I don't know the situations you've seen, but based on my experience:

Most people giving this advice have seen the rookie land and have observed him not finishing the flare. Most rookies aren't jumping canopies that stall so suddenly they can't be flared completely. Those who *are* jumping such canopies might just be DGITs and tend to ignore sensible advice. Even moderately loaded (1.5+) canopies I've seen seem to continue flying for a bit when flared all the way or held in deep brakes.

To address your other bit, stalling a canopy can be quite useful on a moderately breezy day and you want to collapse your canopy once you're fully stopped on the ground. Much easier than fighting the wind.
Brian

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create level flight (parallel to the ground) with the initial toggle input. The rest of the flare is holding level flight, ideally with your feet just skimming the ground.

Continue to flare and hold level flight by continuing to add input until the parachute can no longer hold you up (or stall) and you transition from 'the parachute holding you up' to 'your feet holding you up'.

And as John Leblanc has said many times - just when you are about to plop your feet down and start running, lift your feet up instead and push the toggles another 4 inches to the bottom. The canopy will go further and slow down even more.

If your canopy is stalling during the flare, it may not be set up or trimmed properly. All bets are off if the parachute is out of whack, steering lines are simply too short, or if the canopy is so baffed out that the riggers decided just to shorten the steering lines because it will not flare any more.

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does it not depend on the canopy as well? i go down PAST 3/4 brakes just to get my canopy planing horizontally, as all of the flare power in my canopy (a pilot) is at the very bottom end of the stroke. by the time i burn off horizontal speed i have to flare all the way to finish up and run it out.

and doesnt all of this depend on AOA, wingloading, and speed regardless of the canopy?
gravity brings me down.........

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There is a lot more to flying a canopy than finding the stall point. By the time a novice is jumping their own gear, they should have taken a canopy course.

The advice I give is very much tailored to what I see. Since a very common mistake I see is a jumper landing (hard, fast) with their hands at 3/4 input, I commonly say to flare all the way. Showing them video really drives the point home.

I once saw a student flare all the way at about 50 feet. He stalled that Navigator all the way to the hospital. I would not give him the same advice.

The toggle setting, or brake line length, should be set based on full flight for that canopy. Shortened brakes negatively affect the flight envelope. If you can't stall your canopy, get longer arms, increase your wingloading, or fly with the knowledge that you can do amazing flat turns and sink it in to someone's backyard without hurting yourself.

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Without having read the replies, I'll be brief - you are correct that it's bad advice to tell someone to 'flare the canopy all the way' without knowing how the canopy is set up.

The length of the steering lines will vary depending on the condition of the lines set, the length of the risers, and the size of the jumper (and their arms). Based on that, a canopy needs to be 'set up' with regards to the length of the steering lines to fit a particular jumper and rig configuration. The proper length will have the canopy stall after 4 or 5 seconds of holding the absolute deepest toggle position the jumper can manage.

Provided that has been done, a jumper should finish the flare when landing.

If that has not been done, or you're on borrowed/rented gear, you should find the stall point on jump #1 with that gear, and be mindful of it when landing.

In terms of 'de-tuning' the brake setting, which means setting the brake lines so long that you cannot stall the canopy, the problem there is that you're giving up some degree of flare power. If you can't get the toggles to 101% (aka stall), then you probably can't get them to 99% or 100% either, but that's what you want to do on landing.

Student canopies are de-tuned because the students don't know or understand the stall scenario, and cannot be counted on not to stall on landing. Any flare power they're giving up with the de-tune is made up for by the size and low WL of a student canopy.

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On many canopies at many wing loadings, it isn't that easy to stall it on landing if you have reasonable experience for that type of canopy. We don't have people breaking ankles all the time from folding up their canopy.

Landing problems are more likely to occur from not flaring enough, flaring unevenly, or too high or low.

I've stalled out accuracy canopies, seen heavily loaded Stilettos fold at the end of the flare, and more. But it isn't a common occurrence, even if jumpers need to learn about the stall point on their canopy.

People tend to be saved from stalls during the flare, because normally one is planed out very close to the ground anyway, so an error at the end of the flare has a less bad effect. But if you fully stall out an overloaded Micro Raven or even an accuracy canopy at 10 feet (and miss the tuffet), you might be in trouble. If you are going to stall a canopy on landing, the best time to do so is no earlier than when your feet are 3 inches off the ground and you have already slowed to no more than jogging speed.

If someone flared too high, often they end up mushing down to the ground rather than fully stalling the canopy. The canopy may be out of energy to plane out and fly level, and has to start dropping, but often is not actually stalled. Still, that is one time one really doesn't want to stall the canopy.

You mentioned the issue of someone being told "to flare all the way down". There may be an issue of language and interpretation involved, as the phrase may in effect have the caveat "...but of course only 'all the way' to the point where the canopy stalls, and not past where it stalls, as anyone educated in canopy flight should know." It's those kind of caveats that sometimes get missed, either by the person speaking or the person listening.

A good student training program will include some work on stall practice. The goal may not be to actually stall the student canopy while up high, since that's tough to do, but will at least get the student used to slow canopy flight, signs of a stall, and introduce them to the concept of testing their canopy for the stall point. Whether they can remember that and apply it properly in the future when they start to downsize, that's the next issue...

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tkhayes

...as John Leblanc has said many times - just when you are about to plop your feet down and start running, lift your feet up instead and push the toggles another 4 inches to the bottom. The canopy will go further and slow down even more.



+1

The vast majority of running/hopping/sliding/faceplant landings are caused by jumpers simply not milking the last ounce of flare before putting their feet on the ground. As TK mentioned, keeping your feet up and flaring deeper and deeper until the canopy truly won't support your weight will produce the slowest airspeed before touchdown.
Chuck Akers
D-10855
Houston, TX

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chuckakers

***...as John Leblanc has said many times - just when you are about to plop your feet down and start running, lift your feet up instead and push the toggles another 4 inches to the bottom. The canopy will go further and slow down even more.



+1

The vast majority of running/hopping/sliding/faceplant landings are caused by jumpers simply not milking the last ounce of flare before putting their feet on the ground. As TK mentioned, keeping your feet up and flaring deeper and deeper until the canopy truly won't support your weight will produce the slowest airspeed before touchdown.

And it should be mentioned that there are some cases where the brake lines are too short. I had a buddy that was landing on his butt on almost every jump. I asked him if he was flaring all the way down and he said yes. I was going to watch him on the next landing, but on that landing he didn't flare all the way and had a great landing. So I told him that his brake lines were most likely too short and he was stalling the canopy.

On the next jump I had him pull a bit higher and see if he can stall the canopy. I described what would happen and sure enough, that was the issue.

We measured his brake lines and they were all in spec, it must have been that he has ape like arms. We lengthened the lower brake lines and he is now happy with the canopy.

But yes, 99% of the time people do not flare completely.
"No free man shall ever be debarred the use of arms." -- Thomas Jefferson, Thomas Jefferson Papers, 334

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We measured his brake lines and they were all in spec,



I remember Para-Flite would set their toggles so that you could not stall the canopy without re-setting them.
Other companies have gone the other way so as to impress you with the performance on that first jump.
The truth is that you can't set the toggles at the factory.

Toggle settings will vary with wing loading and density altitude.

Experienced jumpers know that if they normally jump at low elevations and they go to high elevations their flair point will change. It will change from season to season.
That is why you should check your stall point on every jump just after you clear the air.

Flairing past the stall point is not a good idea as you loose lift and the point of greatest lift is just before an impending stall. What good is horizontal drag when you are plumeting vertically?

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You seem to have a misconception about what the stall is. A stall at altitude, even low is dangerous because of the canopy not be able to maintain the flight, just like an airplane in the same situation. But the stall is not so sudden. It takes few seconds to install it on your canopy or airplane. That is where you can benefit from it. When you are at a couple of feet from the ground, pulling your toggles all the way down will give you the maximum support and therefore a softer landing. In this very case, the stall will never happen since you are on the ground before it could happen.
On an airplane Cessna like, just before the stall you have a stall warning alarm. The softest airplane landing happens when you hear that alarm at the touch down of the wheels on the runway. OK it takes some experience and good timing to get that. But if an instructor tells a student by radio to pull toggles down at the maximum just before landing, it's OK.
Also, especially if you have a fast canopy, if near the ground, you pull the toggles down at maximum too fast, your canopy will go up sometimes by 10 ft. To avoid it, pull the toggles down progressively and monitor the reaction of the canopy. Ideally, you should use the John LeBlanc's approach with several steps to observe before landing. 1) you should stay 10 seconds quiet to stabilize your approach 2) at 8-12 ft, you pull partially your toggles down to fly horizontally near the ground 3) you finish your surfing above the ground by applying full toggles down.:)
Learn from others mistakes, you will never live long enough to make them all.

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On an airplane Cessna like, just before the stall you have a stall warning alarm. The softest airplane landing happens when you hear that alarm at the touch down of the wheels on the runway.

When you are at a couple of feet from the ground, pulling your toggles all the way down will give you the maximum support and therefore a softer landing. In this very case, the stall will never happen since you are on the ground before it could happen.



This is horrible advice regarding canopy flight. To flirt with a stall while still airborne because you assume that it 'cant' happen is just asking for trouble. Even a stall at a low altitude can result in a jumper falling on their back from several feet up, and this has lead to tailbone injuries and broken wrists if they reach back to 'catch' themselves.

The comparison to airplanes is fundamentally flawed. The stall horn on an aircraft is calibrated to go off well before the stall, as a warning that you are close to a stall. It does not mean that the airplane is stalled and about to fall out of the sky.

When the wing stalls, it just stalls. There may or may not be a buffet just before the stall, but that's dependent on the pilot recognizing and reacting fast enough to prevent the stall. Otherwise, when the angle of attack reaches the critical angle, the wing just stalls, period.

All of that applies to a rigid wing, like on an aircraft. When you translate that to a 'soft' wing like a canopy, you add in a ton of variables that makes it even less wise to say that it 'cannot' stall.

The line trim, brake line settings, condition of the wing, the WL, and the jumpers performance all add to the 'performance' of the canopy. This is why, unlike every aircraft ever produced, there are no published numbers on the performance of a certain canopy.

Even in an aircraft, it's common to add a few knots to an approach in certain conditions, and that's to buffer you further from the stall speed. The need for this is magnified with a canopy, because again, the performance numbers of the canopy are not 'hard'.

I'll repeat my position from further upthread. Each jumper needs to set-up their brake lines to fit their exact gear configuration, and make it so a stall is difficult to achieve, but possible. This will limit the likelihood that it will occur if things should go 'off plan' on landing, and the jumper starts to do more 'reacting' than 'thinking' at a low altitude. When jumping borrowed gear, they need to make themselves aware of the stall point on jump #1, and be as mindful of that as possible the entire time they are flying that rig.

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davelepka

Each jumper needs to set-up their brake lines to fit their exact gear configuration, and make it so a stall is difficult to achieve, but possible.



I wouldn't do that. I want just enough slack in the brakes so I can pull on a front riser without it applying brake. I don't want two feet of slack just because I have long enough arms to stall the thing if I don't. If my canopy collapses due to turbulence and I need to pull on the strings to re-inflate it, I want brakes not slack.

Set your brakes up correctly and make priority #1 to learn where the stall point is. If you need to detune your canopy because you don't have the skills to avoid stalling it, you should probably up-size and spend some money on a canopy course.

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I disagree with your idea of proper brake setting. Priority #1 has always been preventing a stall on landing, and that's why the 'rule of thumb' has always been that your canopy should stall when the toggles are pulled to full deflection with the wrists rotated so the thumbs are pointed down, and held there for several seconds. It makes the stall difficult enough to achieve, but allows the jumper to reach 100% of the flare power of the canopy.

Yes, if you have long arms you should have longer steering lines. The amount of response the canopy will provide in comparison to the range of motion of the jumpers arms will always be relative to one another, provided the brakes are set as I described. If 100% of your arm motion provides 100% of the pre-flare toggle stroke, than regardless of your arm length, pulling your arms halfway down will provide you with 50% of the pre-flare toggle stroke.

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davelepka

If 100% of your arm motion provides 100% of the pre-flare toggle stroke, than regardless of your arm length, pulling your arms halfway down will provide you with 50% of the pre-flare toggle stroke.



Now what if the first 25% of that toggle stroke is doing nothing but taking up slack in the brake lines because you are afraid of stalling it? Pulling your arms 50% of the way down will give you 33% of your effective brakes.

I land a lot more than I have to dig out of a corner, hence I generally have better fine control at landing and knowing where my stall point is than I do at digging out. If I'm in a situation where I need to dig out, I need to dig out right now and not find that my brake lines are so slack that I've waisted 25% of my arm movement doing nothing useful at all.

I reckon a low turn that I might have been able to dig myself out of is much more likely to kill me than a stall right at the bottom of my flare, especially when I know it's there just like it has been for the last x00 jumps. YMMV.

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JackC1

... I want just enough slack in the brakes so I can pull on a front riser without it applying brake. I don't want two feet of slack just because I have long enough arms to stall the thing if I don't. If my canopy collapses due to turbulence and I need to pull on the strings to re-inflate it, I want brakes not slack. Set your brakes up correctly and make priority #1 to learn where the stall point is. If you need to de-tune your canopy because you don't have the skills to avoid stalling it, you should probably up-size and spend some money on a canopy course.



Jack, I concur. (Sorry, Dave.)

While what Dave suggests may be appropriate for student rigs, I don't think it is once a person gets their own gear.

For example, my Flight Concepts Manta and Man o' War canopies require that I take 2 wraps around my hand of the steering line in order to stall them. No kidding, 2 wraps. There is no way that I should shorten the steering lines until they stall with no wraps. The tail would be pulled down all of the time if I set up my canopy that way.

Perhaps what some people think should be done to set up their steering lines is assuming a high performance canopy, (which even some novice skydivers now have). There are just so many variables. It is difficult to come to an agreement discussing these things online. A person needs to trust someone locally to help them set up their canopy.

I offer this graphic file for discussion: http://www.skydivestlouisarea.com/instruction/steeringlinelength.jpg I have modified it several times to accommodate the feedback I have received, and they changing trend in student canopies.

I made this to show people how steering line length should be set in general. I have already found that some people disagree.

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peek

***... I want just enough slack in the brakes so I can pull on a front riser without it applying brake. I don't want two feet of slack just because I have long enough arms to stall the thing if I don't. If my canopy collapses due to turbulence and I need to pull on the strings to re-inflate it, I want brakes not slack. Set your brakes up correctly and make priority #1 to learn where the stall point is. If you need to de-tune your canopy because you don't have the skills to avoid stalling it, you should probably up-size and spend some money on a canopy course.



Jack, I concur. (Sorry, Dave.)

While what Dave suggests may be appropriate for student rigs, I don't think it is once a person gets their own gear.

For example, my Flight Concepts Manta and Man o' War canopies require that I take 2 wraps around my hand of the steering line in order to stall them. No kidding, 2 wraps. There is no way that I should shorten the steering lines until they stall with no wraps. The tail would be pulled down all of the time if I set up my canopy that way.

Perhaps what some people think should be done to set up their steering lines is assuming a high performance canopy, (which even some novice skydivers now have). There are just so many variables. It is difficult to come to an agreement discussing these things online. A person needs to trust someone locally to help them set up their canopy.

I offer this graphic file for discussion: http://www.skydivestlouisarea.com/instruction/steeringlinelength.jpg I have modified it several times to accommodate the feedback I have received, and they changing trend in student canopies.

I made this to show people how steering line length should be set in general. I have already found that some people disagree.

Hi Gary, I flew a FC Sharpchuter and always set it up where I would take one wrap on landing. It allowed me to do some very interesting steep approached into tight demo targets. People should play around with the setting and see what works for them.

Sparky

This is my canopy.
http://www.flightconceptsint.com/classic/7-cell-classic
My idea of a fair fight is clubbing baby seals

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