Rear Risers Techniques

[hparrish 0]

Interested in hearing who lands with Rears and how. For the last 400+ jumps I've always pinched my rears between my thumb and finger and pulled down on my rears.

Just took a coach course and it was suggested I push out on rears instead. Now obviously I trust this guy or I wouldn't have taken his course, just want to hear others opinions. And I'll leave his name out of it, so as not to scew anyones responses. Lets just say he's a top canopy pilot.

Personally when I tried pushing out on rears (up high of course), there doesn't seem to be as much power in the rears using this technique. Granted I've only tried this several times vs 400 the old way.

[dharma1976 0]

its kinda push out and pull down

D

http://www.skyjunky.com

CSpenceFLY - I can't believe the number of people willing to bet their life on someone else doing the right thing.

[superstu 0]

just depends, don't really prefer either way what ever works at the time. this is pretty standard for me: http://www.youtube.com/user/slipstreamairsports1#play/all/uploads-all/0/erFa7sfimqs

Slip Stream Air Sports
Do not go softly, do not go quietly, never back down

[rhanold 0]

Depends on what I am trying to do. Normal hill, I pull down and slightly out. If I am in the corner I will actually pull them together slightly behind my head (I feel like I get more power/quicker response this way). I have picked up this technique since jumping velos. I pushed out more on FX, XAOS 21/27, and Sensei.

[hparrish 0]

Looks like you are pushing out, but only for a short amount of time.

I tend to grip and pull down, almost flare with rears and ride them out for most of my swoop then hit the toggles to shut down.

No Fancy Belly Mount Camera for me, but I'll try to get my landing footage posted.

[davelepka 4]

When you use the rears, lets say you can deflect the tail 30 degrees before you need to switch to toggles.

If you grab and pull the rears straight down, maybe you get 8 or 10 inches of travel before you hit 30 degrees of tail deflection.

If you grab and pull them to the outside, you still only get 8 or 10 inches of vertical movement before you hit 30 degrees, but you're actually moving the riser through an arc, with the bottom of the riser being the pivot point. So even though you are still only moving the riser the same 8 or 10 inches vertically, the actual distance the riser travels is further than that.

Keep in mind that the shortest distance between two points is a straight line. The same straight line you follow when you pull straight down. This might explain why you feel more power using that technique. You get more output for less input.

When you pull them out, and travel along the arc, the sensitivity (power?) is reduced as you have to pull further to get the same result.

As far as which is better or worse, who knows? The more I think about it, I can't even say which one I really use. I do tend to pull the riser to the outside, unless for some reason I need to pull straight down. Somtimes one goes out, and the other down. I think it just comes down to flying the canopy at all times, and not just pulling or spreading or whatever.

Nobody really asks how you pull your toggles down. It's different every time as you adjust to the conditions. I think risers are the same, just do whatever it takes to make whatever you want to happen, happen.

[superstu 0]

honestly, when i push the risers out i feel like i can make finer/ more precise movements thus letting me keep more speed/energy. when i pull down it's typically when i'm a little low and need a more "forceful" approach to plane out/ stay in the air. so i think for me there is a reason to use each technique, but it's good to have both tools in your tool box.

Quote

No Fancy Belly Mount Camera for me, but I'll try to get my landing footage posted.

it's called duck tape and a GoPro camera

Slip Stream Air Sports
Do not go softly, do not go quietly, never back down

[hparrish 0]

I think the reason I prefer pulling down the rears is just what you hit upon here. I want that Bailout just in case I am low. I also recognize that the Toggles are a more reliable bailout than rears are.

But I do recognize that both techniques are valuable.

I'll still post my video and maybe folks can comment more on what they see.

Thanks to all for your input.

[danielcroft 2]

I'm in my infancy of learning HP landings and am not using rears at all but I am curious so I'm wondering if you guys could answer a question for me.

Would the scale of precision be:

1. Toggles
2. Push out
3. Pull down

Based on what Dave said that precision of pushing out is greater because there's more travel for the same deflection of the tail and that there's an inverse relationship between precision & power (or feel of power)?

Again, I'm not doing this, I was just interested/curious about the technique.

[LetsGoOutside 0]

Quote

just depends, don't really prefer either way what ever works at the time. this is pretty standard for me: http://www.youtube.com/user/slipstreamairsports1#play/all/uploads-all/0/erFa7sfimqs

Like this... sort of a pull out and back a little for me usually.

[blackdog 0]

I have been coached that pushing out is changing the cord of the canopy, which does not lose power. Pulling down however changes the pitch on the C and D line groups which causes more deflection and loss of power.

[davelepka 4]

I going to go ahead and disagree with you on that one. Here's why -

The chord is the measurment from the leading edge to the trailing edge, and I don't believe it ever changes. Deep brakes may technically change the chord, as the air doesn't really flow from leading edge to trailing edge, it sort of gets backed up on the bottom skin, and probably peels off the top skin when it nears the trailing edge. Aside from that. and especially on rears, the chord is a constant.

As far as the pitch of the lines, I'm not sure what you mean. Pitch is an angle, and the relationship between the C and D line groups remains a constant when using the rears. You're maintaining tension on the lines by using the rears for input, and in some cases, the D lines are just cascaded off the C lines so there is no way to pull one without the other. Where one goes the other will follow.

Now in deep brakes, you can take some of the tension off the D lines as the tail and brake lines begin to support more of the canopy, but that's only in deep brakes.

Anyway, the deal is this, whichever way you add input to the rears, that input is indentical for the C and D lines. The pushing or pulling issue shouldn't impact the canopy much for several reasons.

The first is that the outward force of the pushing method will have little effect on the canopy as there is spanwise tension on the fabric to begin with. If say the canopy was bowing upward in between the line groups spanwise (side to side), then pushing outward might take up some of the slack, and make the canopy flatter between the line groups, but there is no slack spanwise, so the input does not effect the span. Pushing out doesn't make the canopy go out, it's already as 'out' as it's going to get.

Second, any input you make at the riser is going to be diminshed by the time it reaches the canopy. Imagine you were holding a string attaced to hook 8 feet away. If pulled straight back in the string, it would have one effect on the hook. If you pulled back with your hand 10 inches to the left, how much different would expect the load to be in the hook? I'm guessing not that much.

To make the analogy correct though, we would have to include the fact that the hook can only move forward and back, not side to side at all. Remember that the canopy is already spread out as much as it can be across the span, so it to is restriced from side to side movement. Even if there was some slack, you would only be able to flatten the middle of the canopy, between the left and right center line groups. All of the left side groups are moving as one, so if the outmost group moves out two inches, so does the one next to it, making the distance between them a constant. By pulling the left and right sides apart, you could flatten out the middle, if the middle needed to be flattened. I can't remember the last time I saw the middle of an X-braced canopy (spanwise) bowing up without broken lines.

I'd be interested to hear who told you this, and (no offense) how accurately you're repeating the information. I'm going to maintain that the primary difference is in the range of motion you can get out of the riser before the stall.

[blackdog 0]

Quote

I'd be interested to hear who told you this, and (no offense) how accurately you're repeating the information. I'm going to maintain that the primary difference is in the range of motion you can get out of the riser before the stall.

dave you are absolutely correct, I was quickly typing and purposely keeping my answer short to gain a nicely detailed response from another trusted canopy pilot like yourself. It is something discussed 2nd from PD training.

Quote

By pulling the left and right sides apart, you could flatten out the middle,

this is really the visual I difference I was briefly eluding to with the difference between pushing and pulling.

Thanks for elaborating with better explanation

[DocPop 1]

Would it not be true to say that pushing the risers out lateraly would flatten out the canopy and make it less anhedral (in the same way that loosening a chest strap does)?

Pulling straight down would probably not have this effect.

I am sure that the effect on the glide of the wing would be negligible, but I do think there would be some slight difference in the way the wing would respond.

"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

[davelepka 4]

Quote

Would it not be true to say that pushing the risers out lateraly would flatten out the canopy and make it less anhedral (in the same way that loosening a chest strap does)?

That's a negative ghostrider.

Loosening the chest strap allows the main lift web to form a straight line from the hip ring to the canopy. This is a longer line than you get when you have the chest strap restricting the MLW, in that case the straight line is from the chest strap to the canopy. The longer line gives you the greater distance at the end of the lines, and the flatter canopy.

For starters, loosening the chest strap effects the entire canopy. Pushing out the rears only effects the rear half of the canopy as the front risers are stationary.

Also, if you think about it, you're introducing an angle into the line from the hip ring to the canopy when you push out on the rears, and the last time I checked if you take a line of a given length, and add an angle, it spans a shorter distance.

Canopies are fairly dimensionally stable in terms of span, chord, and anhedral. The only reason you can reduce the anhedral with the chest strap is that you're effectively lengthening the lines, and it only works because it effects the front and rear risers equally. Anytime you start to use the risers independent of each other (or in groups) the effects to the entire wing are going to be limtied.

[DocPop 1]

That makes sense.

I hadn't thought about it in terms of the fact that loosening the chest strap eliminates an angle in the lines/harness, whereas pulling (down or out) on the rears introduces an angle as you point out.

Thanks for your explanation - interesting stuff.

"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

[jayrech 0]

How many jumps do you recommend some one have before they start to play with rear riser landings, The reason i ask is am a junior diver who has been preforming rear riser landings and rear riser - toggle landings after inducing some speed with my front risers before landing, and one of our swoopers was letting me know how I shouldnt be playing with this. Keep in mind I have only started jumping this year. I understand already that 150 jumps arent that many jumps at all. I do understand the theory/ physics behind dynamic stalls and I know the range I have for the canopy I am under. (pilot 190) Im not underminding the swooper that was instructing me on my follies but I would like some other input in this one as well!

D.S 174.2

Be careful what you say. Some one might take it the right way.

[davelepka 4]

150 jumps seems a little soon to be hitting the front risers. Knowing how to land with the rear risers is a good skill to have, but you might want to put that on the back burner until you have a little more time under canopy.

Let's face it, a guy who has seen you land suggested that you back off. At the very least, if you do yourself in and snap a femur, that guy can rightfully stand over you and say, "I told you so", and let's face it, nobody wants that.

[JohanW 0]

I *just* started reaching for the rears again, almost as if by accident. I have done it before, two or three times when I had about a thousand jumps. When I feel current, say after the tenth jump of the weekend, the weather is nice, not too much wind, and I come out just right after a swoop and have the time, I find myself going to rears.

If you want to land with rear risers, maybe do not induce extra speed, just set up a nice long final, take the time to go to rears, take a deep breath and level it out on rears. Flare on toggles. This sets you up with more time and inner calm than when inducing speed.

All of this is not a substitute for high H+Ps, a lot of them (find a friend! do CRW!), and slowly building the sight picture for your induced speed landings without any rear risering for now.

I haven't seen you land. And it's very different from person to person. But if someone says you should go easy for now, I think he's right. Work on accuracy, flaring itself (keep it flying and finish your flare), flat and flare turns, cross- and downwind landings, and do not use rears to extend your surf for now.

If you really want to hear a number, 500 for swooping, 500 swoops for rear riser swoops. Those are minimums. But currency is important, and experience, time, talent, coaching. It's really hard to pin a number on it. I really shouldn't. And the next guy will have a different opinion. This is just mine.

A Pilot 190 is really not an ideal canopy to perform these kinds of stunts on BTW, its recovery arc is too short and the risers are too heavy. You have to set up low and giving exactly the correct amount of input is difficult.

Johan.
I am. I think.

[rhys 0]

It surprises me how much you pull your front risers down, I have not jumped a velocity much, so can't compare, But i would think with my canopy (JVX79) that if i pulled my front risers anywhere near as much as you did in that video i would be increasing the parasitic drag, deforming my wing and therefore losing performance, speed and distance.


I used to pull my rears and push my rears but have learned a new (to me) technique of snapping the rears into place ( the point where the canopy is trimmed as flat as possible without distorting the airfoil). at a point where it will surge me forward across the ground. I have gained much more distance since adopting this technique. speed i am not so sure of?!?!?

"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

[davelepka 4]

Quote

I used to pull my rears and push my rears but have learned a new (to me) technique of snapping the rears into place ( the point where the canopy is trimmed as flat as possible without distorting the airfoil). at a point where it will surge me forward across the ground.

There is no such thing as 'surging forward' without added thrust. It's just impossible.

If you're using a sharp input on your rears, what you're feeling is your accelerated forward swing under the canopy. This is happening because you're introducing drag to your wing, and slowing it relative to your speed as a jumper. The wing moves back, the jumper moves forward.

There is a 'sweet spot' where you balance the amount of drag you introduce in accelerating this process vs. letting it happen slower while introducing less drag to the wing.

At first it would seem that the process introducng less drag would be preferable, however that process will take more time to complete, and during that time you will be losing speed due to the natural drag of the canopy/jumper and the lack of thrust.

[timmyfitz 0]

Quote

There is no such thing as 'surging forward' without added thrust. It's just impossible.

Or reduced drag?

[rhys 0]

Hi Dave,

As we all are constantly learning new techniques and results, I cannot realisticly describe the physicis involved, i was pulling the risers down and getting good swoops, I was also pushing them out with similar results.

AVery experienced swooper gave me the advice to snap the rears into place, his word wen't somewhere along the lines of;

"bro, you are doing good, try snapping your rears instead of milking thim into place..."

I tried and after a few jumps i was adding at least 20m to my landings. Once the rears are in place, I do not move my hands at all (unless I am carving), and i am on rears for a substancial distance along the ground before transferring to toggles to finish it off.

I am not saying that my technique is the best and I am no champion (yet), but kinking the risers and reducing thier length by half and only being on rears for a split second, seems like poor technique to me?

I lose 900ft in a 270 and i do it slow, my front risers are not pulled they are guided through the turn and the result is a shitload of speed.

ther are many ways to do an approach and I hope to find the perfect one, distorting the canopy by such great amounts does not seem to be a good idea to me.

But hey, thats just me right?

"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

[davelepka 4]

Quote

"bro, you are doing good, try snapping your rears instead of milking thim into place..."

I tried and after a few jumps i was adding at least 20m to my landings. Once the rears are in place, I do not move my hands at all (unless I am carving), and i am on rears for a substancial distance along the ground before transferring to toggles to finish it off.

That's exactly what I was saying. We're on the exact same page, I was just more accurately describing the 'surge' you were talking about.

The idea is to transfer from diving to level flight losing the least amount of energy. When you 'milk' the rears, you're introducing less drag per second over a longer period of time. During that time the natural drag of the jumper/canopy is slowly chipping away at your speed. The longer you milk them, the more eneergy you lose due to the natural drag of the system.

When you snap the rears, you're introducing a large amount of drag all at once. For one or two seconds the amount of drag is considerable, but when you snap the rears like that, you accelerate your swing forward under the canopy. Once you swing forward far enough, line tension pitches the nose up enough that you can release (or simply maintain) the pressure on the rears and still maintain level flight. After the one or two second spike in drag, you reduce it to very little for the remainder of the swoop.

There is a point where you add too much drag, like digging out of the corner. It robs your speed as you have to give too much input for too long.

Likewise, there is a point where your roll out is too gradual, like when you swoop a little too high. As you make that long gradual roll out, you lose all your speed.

In your case it turns out that your 'milking' technique was too far on the 'slow and easy' side of the equation, and you were sacrificing speed. When you switched to the 'snapping' technique, you simply got closer to the ideal ratio of lift to drag over time, and went further.

[davelepka 4]

Quote

There is no such thing as 'surging forward' without added thrust. It's just impossible.

--------------------------------------------------------------------------------


Or reduced drag?

Six of one, half dozen of the other.

When talking about a non-powered aircraft that requires an increase in the angle of attack to produce thrust, and talking about that aircraft in the last 30 vertical feet of it's flight where increasing the angle of attack is not possible, I prefer to reference the lack of thrust side of the thrust/drag equation.