Bucking on front riser turns

[steve1 5]

I have dive loops and have been experimenting with front riser turns and double fronts for altitude loss. Every time I've tried this I have experienced bucking from my canopy. I knew this was because my toggles were set too short. I have let them out until now I have them at the very ends of the steering lines. There is at least six or seven inches of play on my steering lines. I can pull them down this far before a turn starts. My next thought was maybe I'm pulling my front risers down too far. I doubt if I'm pulling them down much more than 5 inches before the bucking starts. Anyone have any ideas? No one at my DZ seems to know much about front riser use. Thanks, Steve1

[Hooknswoop 19]

The length of the steering lines can drastically affect how a canopy flies. High performance canopies are affected much more than lower performance canopies. All canopies should have some slack or a slight bow in the steering lines. If the steering lines are too short and pull down the tail of the canopy during full flight, even slightly, the canopy is flying in brakes. If the canopy is flying in brakes, it will not have as much speed to trade for lift during the landing flare. Over time the steering lines shrink as a result of friction from the slider during opening, as much as 6 inches in extreme cases. New canopies or line sets adjusted to have no slack in the steering lines will begin to fly in brakes as the control lines shrink.

To maximize the performance of your canopy it is necessary to understand the construction of the steering lines. The steering lines on a canopy are made of several parts. The upper control lines, usually four or five lines cascade or split at the top of the central control line and attach to the tail. The central control line attaches the upper control lines to the lower control line. The lower control line attaches from the finger-trapped loop (for setting the brakes) at the bottom of the central control line to the toggle. The lower control line is where your rigger can make adjustments.

If you do not use your front risers, adjusting steering line length is a fairly simple process. To check your control lines, pull one toggle down an inch or two while watching the tail of the canopy in flight. The tail should not move and the canopy should not turn. If it does, your lower steering lines need to be lengthened. Make small adjustments, no more than an inch at a time. This may require several adjustments. It is better to be an inch too long than an inch too short. Once you find the correct length, have your rigger finger-trap and bar-tack the lower steering line to eliminate the knot next to the toggle which can hang up on the guide ring. Periodically check the steering lines to see if they have shrunk and need to be lengthened again. Micro-line can shrink 4 to 6 inches or more over its life span. Vectran tends not to shrink with wear but is not as durable as Micro-line.

If you use your front risers, adjusting steering line length is more complicated. Having enough slack in the lower steering lines on a high performance canopy is more critical to how the canopy will fly. In a front riser turn you are pulling the toggle down a little with the riser and there has to be some slack to prevent pulling down the tail. If the tail of a high performance canopy is pulled down even a little when front risering, the riser pressure will be much higher and the recovery arc (the amount of altitude required to get back under the canopy) will be shortened. To check if the steering line is long enough, clear your airspace, do a full 360 degree front riser turn (keeping the toggles in your hands), and watch the tail of the canopy. As the speed increases, the drag on the control line increases and if there isn’t enough slack, the tail will be pulled down. You need enough slack so that the tail won’t be pulled down while pulling the toggle and the riser down at the maximum speed of the canopy. Again, make small adjustments no more than an inch at a time and have your rigger finger-trap and bar-tack the lower control line once you have them adjusted correctly.

With the steering lines correctly set, your canopy will dive longer and faster and you can get the most out of your canopy.


What type/size/wingloading is your main?

Hook

[steve1 5]

Hook,
Thanks for all the input. I'm just wondering how far you usually pull your front riser down to make a turn. I imagine a fast turn would be further down. My steering lines on my new Hornet may have been manufactured too short, since I can't move my toggles down any further now. They are presently on the very ends of each steering lines, yet I'm still experiencing some bucking on riser turns. We do have a couple guys at our DZ who make swoop landings on small canopies, but I think they are doing this with a toggle turn. So neither of these guys are a good source of information about using front risers or adjusting toggles for front riser use. I know this opens up another subject area because from what I understand hook turns with toggles can be a real killer. I'm far from the point where I would ever try a hook turn, but I would like to mess around with front risers up high. I'd also like to use double fronts to get down out of crowded air space. Thanks, Steve1

[AggieDave 6]

That's odd, on my Heatwave (another PISA canopy) I had literally an extra 8" of steering line after setting up my brakes.

--"When I die, may I be surrounded by scattered chrome and burning gasoline."

[Hooknswoop 19]

If you have Spectra lines, they may have shrunk to the point that there is no longer enough excess steering line to place the toggle far enough down on the control lines to prevent bucking.

Where, in relation to your body, are your hands when you finish your flare?

Hook

[SkydiveMonkey 0]

I don't have much play, if any, on my hornet 170

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[steve1 5]

Hook,
I've been taking all the slack out of my steering lines on my approach. This leaves my hands slightly above my head. On the initial part of my flare I bring the toggles down below my chin to level out and then slowly bring them down to finish my flare as the speed bleeds off. If I pull them all the way down my canopy won't stall. I've tried this a lot up high. There's too much slack in my lines for it to stall. This hasn't been a problem though. I can still get a good landing without having more flare. I'll try what you mentioned about watching the tail next time I make a front riser turn. Thanks, Steve

[parachutist 2]

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I knew this was because my toggles were set too short. I have let them out until now I have them at the very ends of the steering lines.

A few months ago I bought a new Xaos-27 and I was experiencing similar bucking (it was making a loud WHAP WHAP WHAP noise too). THe problem was as you guessed: brake lines were set too short.

- So I lengthened them, went for a jump & still had the problem..
- lengthened them some more, went for a jump & noticed the bucking was not so extreme now...
- lenthened them again (this time the brake toggles were as far down the lines as I could place them) and now I noticed that I only had the problem when I'd get pretty deep into risers
- So now I wanted just a bit more length in my brake lines, but I was at the end of those lines. So I called Precision and they sent me a longer pair
Chris

[parachutist 2]

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If I pull them all the way down my canopy won't stall.

Then again, if you can't stall your canopy now, adding more slack to your lines would probably not be a good idea. That would put more of the flare potential out of your reach =\

Chris

[crazy 0]

Quote

If I pull them all the way down my canopy won't stall. I've tried this a lot up high. There's too much slack in my lines for it to stall.

So, don't lengthen them anymore. They might even be too long already. When your lines are too long, you loose some controlability during the flare, under some circumstances it can be dangerous (unsuspected turbulences or the asshole crossing right in front of you for instance). In addition you will have shorter swoops.

Quote

I have dive loops and have been experimenting with front riser turns and double fronts for altitude loss. Every time I've tried this I have experienced bucking from my canopy.

Bucking is normal if you pull too much on both risers (you create a step between the B and C lines).
Now, if you have some bucking when you pull only one riser, it's really surprising. Your canopy is a hornet 170, right? What wing loading? Do you have long or short arms? How deep do you burry your riser?
--
Come

[alan 1]

You might want to check the trim specs on your outboard "A" lines. It is possible they have shrunk or are simply just out of trim. They could also be the cause of the bucking and may even contribute to a partial collapse under the right circumstances. Just a thought to toss in with the other answers.

alan

[bobsoutar 0]

If I pull them all the way down my canopy won't stall.
Might seem a bit pedantic but are you just pulling your toggles down, or down and out to the side? Ideally you should be flaring with chest out and hands coming down, out and slightly behind you at approximately 45 degrees to your shoulders - this creates a pulley type of action with the steering line passing through the ring on the riser.

[rhino 0]

Quote

Then again, if you can't stall your canopy now, adding more slack to your lines would probably not be a good idea. That would put more of the flare potential out of your reach =\

I second that

[sroberts 0]

Another problem might be your dive loops...where are they on your front risers?

[steve1 5]

sroberts,
That's a good question. The loops are on a standard pair of mini-risers. They are fairly high up on the front risers. If they were much higher I'd have trouble reaching them. I'll do some more experimenting. Earlier I had my toggles set about three inches shorter than they are now and my canopy would still not stall in full breaks. I have a Hornet loaded at about 1.2. I'm just wondering if it is normal to have 6 or 7 inches of play in your toggles to avoid bucking problems with front risers? Steve1

[PhreeZone 20]

Steve, what size risers do you have? 18 inch, 21's or something else? you might just need to move up to a different size riser if 2 inches either way of factory does'nt change the canopy till you can stall it.

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