Dangers in toggle turns vs front riser turns (Adria's accident)

[billvon 2,396]

This is the continuation of a thread from the Incidents forum.

Adria's incident occurred after a 270 degree toggle turn. The issue that was raised was - is it safer to do a toggle turn or a front riser turn to prepare for a high performance landing?

First off, let me state the obvious - that training in EITHER method is going to greatly decrease your odds of getting hurt, and no one should try such a manuever without both training and a lot of experience at lesser manuevers.

But everything being equal, in most cases, a front riser turn is going to be safer. Why? Because you can bail out more easily. Try the following experiment -

At a safe altitude (>1500 feet) yank a front riser down until you have turned 180. Now recover as hard as you can - drop the riser, level the wing and use both brakes to pull out of the resulting dive. Notice how long it takes.

Now try the same thing with a toggle turn. Turn 180, then bring down the other toggle to level the wing, then try to use both of them to stop your descent. Which one gave you a more powerful recovery? In most cases, you will be able to recover more quickly with the front riser turn. Why? Because you have put yourself in a situation where you are diving at the ground without any brakes applied. Adding brakes will have an immediate and drastic effect; it will cause you to swing rapidly under the wing, and that will give you a tremendous amount of lift. If you use toggles to start the turn and then both toggles to level the wing, you have already "used up" your brakes; you are descending at a high rate of speed with little lift left to pull out of the corner you've put yourself in.

To answer one person from a previous thread:

>I have just started front riser turns up high and they seem to lose
> altitude at a very high rate and are much harder to control.

Quite true; you have to practice them to get good at them. However, once you drop the front riser and are on brakes, you have a lot more in the way of options after a front riser turn.

[parachutist 1]

Another downside to toggle turns for inducing speed: It's easy to put a high performance canopy into line twists by giving it quick toggle input. Up high it's an annoyance, but down low it can easily be fatal.

Front riser input with modern canopies does not create line twists... so there's another point in favor of front risers for high performance landings.

[parachutist 1]

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If you use toggles to start the turn and then both toggles to level the wing, you have already "used up" your brakes; you are descending at a high rate of speed with little lift left to pull out of the corner you've put yourself in.

The "Pendulum Effect" was explained to me years ago in a canopy control class, and I think it explains the reason for this lack of flare very well.

When using a brake toggle to turn, one side of your canopy slows down. After you let up on that brake toggle, that side of the canopy will speed up (surge forward) to match the other side of the canopy. This means the pilot swings back (like a pendulum) as the canopy accelerates forward... then the pilot's weight won't stay back, so the pilot swings forward (swing #2 of the pendulum)... now the pilot swings back again(swing #3) into normal position under the canopy. After swing #3, the pilot's canopy recovers back into normal flight and the pilot can flare.

High performance brake toggle landings are done with the intention of swing #2 happening at ground level, so that the weight swinging forward is part of the flare process.

But if the swing #2 (the pilot's weight goes forward) happens too high, say at 30 ft .... the next step is the pilot swinging back and the canopy surging forward toward the ground. There is no flare for the pilot at this point.

And if the pilot needs to flare during swing #1, he's very much out of luck because there is negligible flare... the canopy is surging forward and that's all it's going to do during this stage. Too low.


"Pendulum Effect" for Front riser dives:

Front riser turn is initiated and pilot's weight swings back... air speed increases and pilot's weight stays back. Let up on the riser and pilot's weight swings forward (swing #1). Then the weight swings back into normal position (swing #2) and recovers to normal canopy flight. So the pendulum effect has fewer steps when doing front riser dives. 1 less step in this pendulum effect than when doing toggle turns... simpler is easier.

High performance front riser landings are done with the intention of swing #1 happening at ground level, so that the weight swinging forward is part of the flare process. Using the front riser dive offers much more room for error in this department than the brake toggle turn... because if the pilot comes out of the front riser dive too early, he can prolong the time during which his or her weight remains behind the canopy (by using double front risers to go straight ahead).
The pilot who uses a brake toggle to induce speed does not have this luxury... he can continue the turn so that his weight will stay behind the canopy, but this endangers others because he'll end up landing off the wind line, possibly colliding with others.
Supposing the pilot realizes that he's low in his front riser dive? He can flare and have a much quicker recovery than the pilot who used brake toggle turns. The front riser dive only requires 1 swing for recovery, and that swing is in the correct direction. For the brake toggle turner two stages are required, as mentioned above: The canopy surges forward.... then after this stage the pilot's body swings forward and he can flare. Timing is not very forgiving for low fast toggle turners

***************
Those are the dangers of the Pendulum Effect.... of course if either of these methods is used at low altitude, there is a high risk for severe injuries, so they're both very dangerous and canopy coaching is the best way to learn. Trial and error is painful

[Fast 0]

I think that is one of the best posts that I have ever read regarding the differences of these two types of turns.



/golf clap

~D
Where troubles melt like lemon drops Away above the chimney tops That's where you'll find me.
Swooping is taking one last poke at the bear before escaping it's cave - davelepka

[tfelber 0]

Thanks Bill, I wasn't sure how to start a new thread without losing a number of people who had input on these maneuvers.

From this conversation I now understand two new facts regarding diving turns:

1. Front risers while being more difficult than toggle turns give you full "flarability" because the toggles are not partially used to initiate the turn.

2. With front riser turns your body swings less and the recovery time is therefore less.

Combining these two leads me to believe the time necessary to recover from a bad situation is greatly decreased with front riser turns and controllability is greatly increased by having full toggle input available.

One person mentioned that in a turn (and I'm sure we're talking extreme turn)

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you do not have immediate control of your canopy

I don't really understand this. It seems to me the load on the canopy would actually increase with the momentum which would make the canopy perform more like a fixed wing and therefore respond quicker to pilot input. I haven't experimented with this yet so I have no direct knowledge only theory.

Anyone???

[tfelber 0]

Very good points! I've noticed up high that the recovery from a toggle turn seems very smooth with me easily being able to tell when I'm no longer diving by the sound of the air rushing by, however with no reference to movement I probably forget to pay attention to my body position in relationship to the canopy. I aslo have a tendancy to use the other toggle to decrease the time it takes for me to return to level flight which if done properly would work out great, but there's a lot more room up high than when you start getting close to the ground and small changes can make a big difference.

[ccowden 0]

Am I to understand correctly that she was actually attempting a high performance landing using a 270 degree toggle turn? I have never seen someone move to 270 degree finals and do it using toggles. If you are at the level in canopy piloting where you are doing 270s, you should definitely be of the experience level to know that toggles just don't make sense. One of the first things one should learn in moving to high performance landings is the carving front riser turn. How does someone get to the point at which they are trying 270s and still using toggles? Or was this just a general turn that was not intended to be high performance?

[flycurt 0]

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Can you possibly tell us Curt, as to whether she was advised or instructed in advance of these "outs", and further how to recognize the need for them and how/when to best execute them?

My name is Curt Swanson, I have been a FreeFly Load Organizer at Perris for nearly 2 years; I have over 1800 High Performance Landings (HPL) and am qualified as an advanced class pilot on the Pro Swooping Tour. The information I am writing here is for reference only and to be used at your own risk. It is not a substitute for "Qualified" instruction, which should be sought out by anyone who intends to pursue HPLs on any style of canopy. Additionally, if you have not trained all your techniques up high before bringing them lower to the ground, you are skipping important steps in proper progression, placing yourself and others at added risk.

"Outs" are alternative landing lanes or headings a person would take if their intended landing must be aborted due to low altitude, winds, traffic or any other reason. Outs should be part of a person's landing plan, at least 2 outs are part of a good plan.

Outs are your safety net once you have committed to a diving turn, but they should be planned and used if indicated. Also, consideration must be given so that if you need to use an out, you still have clear airspace through your out. This consideration is given before the execution of your turn. This means that if you decide to take an out, that you aren't going to cut across another jumpers path or buzz another jumper close aboard, where your sudden presence causes them to take some evasive action that now puts them into a dire situation.

If that happens more than once, you are either just a selfish ass, or you need more canopy piloting skills before continuing with swooping, in which case you need to STOP doing HPL's or diving turns until you can demonstrate improved judgment in your canopy control and piloting skills.

Execution of an out is fairly simple. To properly learn how to do a HPL or diving turn, Your airspace should be well clear(~500' radius around you) and you should be looking at least 90 deg AHEAD of your turn, in the direction of the turn. As you begin to descend, if you feel you might not have enough altitude to complete the turn to your desired heading, stop the turn by going neutral on your controls, make sure you don't have traffic, use your out, and land on this new heading. Additionally, the out that you are taking should not end up going across an area where there is potential danger, i.e...the main landing area, the runway, into the packing area. These would be examples of poor planning if you need to use them. Dirt dive your landings and visualize what you would do if the unexpected happened. Use common sense. Ask questions.

If you are learning and/or training to perfect your technique on HPL's or diving turns, don't do them over the main landing area if there is any traffic whatsoever, you should be using hop~n~pop's for clear airspace, or a landing area well clear of the main landing area if you are in such a status. Just because a qualified or seasoned swooper might be doing them over the main landing area, does not mean you should.

I have an advantage of being able to see many top swoopers at my DZ and I watch them when I can. I have on many occasions seen them abort a HPL due to traffic; if they can abort their landing, so can every other person, myself included. There is no reason to force a bad situation.

Good Luck!

[tfelber 0]

Some of the people at the DZ said that she had intended to perform a 270 degree turn prior to getting on the load. They also said that she had not been practice high performance landings and they seemed quite shocked that she had attempted it.

This may all be hearsay, but it was more than just a couple of people that mentioned it.

For your other question. Prior to the converstion started in the incident forum regarding front riser vs. toggle turns if I was going to try even a 90 degree approach I would have tried it with toggles first for several reasons:

1. I have much more experience using toggles to control the parachute than risers.

2. As I mentioned in a previous post, I felt the recovery from a toggle turn was much more gradual and controllable.

3. Front riser turns seem to be much more ground hungry because I'm pulling the leading edge of the canopy down rather than letting resistance on a corner of the trailing edge induce the turn.

4. Front riser turns require much more energy to start and to maintain.

So it would be very easy for me to imagine someone, including myself, attempting a high performance landing using toggles rather than risers had they never had the discussion we are having right now.

Many of my friends who are well known swoopers have mentioned riser turns for high performance landings but since I never really considered doing one I never asked why. I went about with my bag of assumptions and could have been severly injured had I stuck with those assumptions and tried such a maneuver!

[ccowden 0]

I can see someone using toggles to do a 90 degree turn when just learning their canopy. But to be at the point of attempting a 270 high performance landing and still using toggles, just doesn't jive.

[tfelber 0]

I'm not sure from reading the posts regarding Adria incident or from talking with the people that were at the DZ when it happened if she had ever attempted anything more than possibly a 90 degree approach.

[PhreeZone 15]

At one of the DZ's I jump at there is a pilot that does snap 180's or 180+ toggle whip turns as often as possible. He started jumping and there was no one at the DZ doing front riser approaches and he built up a lot of jumps on the toggles at 90 and 180 because thats all he knew. The DZ is still pretty old school in that very few people actually know how to properly use their front risers and all the instructors do toggle whips so thats all upcoming students see.

I once asked this jumper with 1300+ jumps about trying front risers and he commented it took more effort and that he was probally safer since he's so used to the toggles that he can nail it where he'd have to go back to the start on risers and its not worth it for him.

Yesterday is history
And tomorrow is a mystery

Parachutemanuals.com

[ccowden 0]

I could be wrong, but I thought I read somewhere that she was doing a 270 toggle turn. That is why I was curious if it was just a bad turn that happened to be 270 degrees, or actually an attempt at a high performance landing.

[Damion 0]

well put. :D

[Zenister 0]

ive seen one or two visiting teams that were doing toggle turn approaches nearly every time and nearly everyone commented and cringed on occasion on them on the out going trams.

I guess i'm lucky in that i have had people show me the difference in where you are in each approach early on, but it seemed like the toggle turners were clearly the 'old school' exception and that the people that were doing it had been doing it so long they were 'scary' but fairly proficient, but I'd never seen much more than a 180ish toggle turn.

That is why it shocked me to hear she intentionally attempted a 270 toggle..

____________________________________
Those who fail to learn from the past are simply Doomed.

[flycurt 0]

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I once asked this jumper with 1300+ jumps about trying front risers and he commented it took more effort and that he was probally safer since he's so used to the toggles that he can nail it where he'd have to go back to the start on risers and its not worth it for him.

I'd have to agree with this jumper to some degree. Whether using toggles, fronts, rears, harness or whatever combination of canopy controls a pilot decides to use, you have to ask yourself, what is the goal of the pilot under their canopy?

If you are a video person who likes to whip your canopy around with toggles and are safe in doing it, so be it. It's what you know, it's what you've done after 100's or 1000's of jumps. I don't believe it's as safe, but people who do it enough know it's no big deal to them. But as you point out it's not a great example of what to do for students. Unless of course they pull every student aside and educate them on what and why, which I know doesn't happen very often.

If you are a CReW person, you're going to use all kinds of combo's, ask a CRew Dawg what inputs are needed to "warp" the canopy. Sport accuracy jumpers, these jumper's sit in brakes alot of the time until they arrive at just the proper angle/altitude.

But if you are doing HPL's or diving turns to build up speed for distance or a speed run, you are going to use your fronts to change the shape of the canopy to turn and dive. This will keep the canopy fully pressurized, without deflecting the tail, which would slow the canopy. It doesn't make alot of sense to slow the canopy if you are trying to build up speed.

Using toggles deflects the tail to whichever side the input is given. This begins to "move" that side of the canopy toward a stall, slowing or "appling the brakes", to the side of the canopy that is deflected. And the turn is then initiated by the other side effectively "out flying" the stalled side. Then, once in a diving position the canopy controls can be put to a neutral/full flight position where the canopy will settle on heading and pick up more speed as you descend and begin to swing back (pendulum effect) under the canopy.

Using fronts distorts the shape of the wing to effect a diving turn, allowing the wing to immediately build up speed as it descends through the air. You still get into the diving position as you do by swinging out using toggles, but by the time you reach this position using fronts or harness you are going considerably faster and have used up more altitude to get there.

There are established maneuvers and control inputs for desired effects, but the proper way to land depends on your end goal of how you like to land.

Be safe!

[Tonto 1]

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I once asked this jumper with 1300+ jumps about trying front risers and he commented it took more effort and that he was probally safer since he's so used to the toggles that he can nail it where he'd have to go back to the start on risers and its not worth it for him.

That could have been me until about 18 months ago.

I'd been jumping Jonathan's since 1992 and they didn't respond well to front riser input, resulting in me having around 3000 HPL's with toggle spanks. Buying newer US gear was prohibitivly expensive at the time due to a high exchange rate. (I'm not from the US..)

As the dollar weakened and the cost of gear came down, I bought a 2nd hand Stilleto 107 and with help and input from several people on these forums, (Thanks Chuck) I set about learning new tricks as an old dog. Now, 450 front riser turns and 16 months later I've again bought a 2nd hand Safire 119 to explore its longer recovery arc over the Stilleto. (and to use in my birdman rig.) I think maybe 500 - 800 dives on this would be a good stepping stone to a crossbrace of even wingloading.
I've been doing this 20 years. I'm in no hurry to get good one day.

As an old CReW dog, I like to think that both toggle spanks and riser carves (or any other input, really) are what you make them. I did toggle spanks safely for 1000's of jumps, and I've seen several riser turners lose a toggle and femur themselves.

It's the pilot who makes a difference, and I think that HPL's are dangerous and that debating which is "safer" is a misnomer. The primary reason for using your risers should be for the higher performance gain, not the lesser risk exposure.
That's what my motivation was. To learn a new trick that we simply could not use on the rags we started with.

That's my thinking, anyway.

t

It's the year of the Pig.

[davelepka 4]

***you do not have immediate control of your canopy
---------------------------------------------

I think I said this in the other thread. The idea is that any change in pitch or roll for your canopy is dependent on your body shifting in the opposite direction of the intended movement, i.e. if you want to turn left, your body weight will have to shift to the right for this to happen.

If you are already off to the side of your canopy (in a turn) and need to flare, your body weight needs to shift out ahead of your canopy (causing the canopy to pitch upwards and arrest your decent). The further your body weight is from the neutral center position (where it is during straight flight) the longer it takes your body weight to facillitate your intended changes in direction.

The difference in 'time to control response' for your canopy between recovering from a toggle turn as compared to a riser turn is not that great. Although the difference is slight, every step you can take to stack the cards in your favor is an important one. A riser turn can and will put you into an unrecoverable situation very quickly.

In response to the incident in question, the toggle turn may have been used out of neeed. At the low-ish wing loading the female jumper was at, a 270 front riser turn may have taken more strength than the jumper had. The toggle turn on the other hand, would have been much easier to manage.

[kallend 1,623]

Something that hasn't yet been mentioned (I think) that may be relevant is that it's much easier to overcontrol with toggles than with front risers.

It's easy to get into a situation where you can see the horizon above your canopy in a toggle turn. I've never managed anything close with a front riser turn.

...

The only sure way to survive a canopy collision is not to have one.

[Jib 0]

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But if you are doing HPL's or diving turns to build up speed for distance or a speed run, you are going to use your fronts to change the shape of the canopy to turn and dive. This will keep the canopy fully pressurized, without deflecting the tail, which would slow the canopy. It doesn't make alot of sense to slow the canopy if you are trying to build up speed.

***
Using fronts distorts the shape of the wing to effect a diving turn, allowing the wing to immediately build up speed as it descends through the air.

Don't front risers alter the angle of attack rather than distort the canopy? Or is it just less distortion?

--------------------------------------------------
the depth of his depravity sickens me.
-- Jerry Falwell, People v. Larry Flynt

[flycurt 0]

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Don't front risers alter the angle of attack rather than distort the canopy? Or is it just less distortion?

Yes, using fronts will alter the AoA of the entire canopy, but that alteration first affects the portion of the wing connected to that riser, so as it's AoA is changed relative to the rest of the canopy, the entire wing will then change its AoA and "behave" according to the control inputs given.

The word "distort" might be misleading or is the wrong description but using a front riser changes the shape of the wing, and this shape causes the wing to fly into a dive. I am not an aeronautical engineer by any means, but my comments are meant as general references, not necessarily the exact engineering terminology.


Angle of Attack: The acute angle between the chord of an airfoil and a line representing the undisturbed relative airflow.

Chord: A straight line connecting the leading and trailing edges of an airfoil.

[billvon 2,396]

> I can see someone using toggles to do a 90 degree turn when just
>learning their canopy.

I can also see people doing 90 to 180 toggle turns as more of a "survival" manuever - I've made it back to the DZ with very little altitude to spare on a few occasions and done a 180 toggle/flat turn to get me turned into the wind before landing. I sometimes worry that people may see such manuevers and think them a good idea as a way to increase their swoop.

[base698 1]

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It is not a substitute for "Qualified" instruction, which should be sought out by anyone who intends to pursue HPLs on any style of canopy.

Qualified instruction is great as they do offer lots of background information, as well as have the ability to show the jumper if they are digging out of the corner. Newer swoopers certainly need to see this if they are doing it over and over. It is in my experience that qualified instruction does not drill into the slow progression regarding turns, as well as provide the necessary experience needed.

Slow progression, which I think is the most important part is straight ins, double fronts, 90s, 180s, and then onto 270s and bigger turns. At each interval you should do A LOT of jumps. This does not mean five 90 degree turns and then do a 180 degree turn. It means at least a hundred. If you do this on every new you will likely develop a site picture that can later save your life when you are digging out of the corner on bigger turns. Once you are able to do 270s you can downsize, but then you have to start over. This means when you are doing 270s at 1.3 and you downsize to a 1.5 you have to start the progression over from scratch because you will not recognize the corner anymore on that canopy and you will bounce.

I think I am alive at this point solely because even though I was a terrible canopy pilot at 400 jumps with a too high wingloading. I still stuck to that progression.

[dreamsville 0]

There was a person who initiated a strong toggle turn at 1500 feet recently. The canopy twisted and the cells were not totally and properly inflated through the landing, by the jumper's admission. The jumper was more scared after the incident than during once time was available to think it over.
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I don't drink during the day, so I don't know what it is about this airline. I keep falling out the door of the plane.

Harry, FB #4143