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Hey,

following up on the cliff-strike thread, I'm wondering what kind of turn-radius people are getting when turning away 90 degrees or more on rear-risers.

In my practice-skydives, I feel like I can back up the canopy on rear-risers and then by slowly letting one up, I can pretty much turn in-place, meaning the axis around which I turn goes through the center of the canopy. Basically one side of the canopy is flying backwards, and the other side is moving forward.

It's hard to tell because there is no reference points, so I'm probably full of sh*t, but it does feel that way. I suppose I should do some CREW to get some notion of what's relative.

Anyway, back to the topic at hand; is it possible to make such a turn (sucking up altitude quickly I imagine), effectively allowing you to avoid a cliff-strike when you're as close as half the diagonal-length of your canopy?

You'd have to add response time and minor forward surge on opening (with proper brake-settings), so in reality the distance will be greater, but I'm curious to know if such "in-place" turns are possible.

Cheers,

Jaap

I don't think they're quite "in place". The non-stalled portion of the canopy (the side you're not pulling on the riser under) has more forward speed than the stalled side (the one you are pulling on) has backward speed.

In order for the turn to happen in place, you'd have to equalize those two speeds (i.e. the vector going backward on one side would be equal to the vector going forward on the other). In reality, the forward speed is usually noticeably greater than the backward speed, so you end up moving forward overall, throughout the turn.

I wonder if you could do a "partial riser stall turn" where you pull one riser down a lot (to move that side slowly backward) and the other down a little (to slow that side's forward movement) and achieve the "spin in place" you are talking about? And how much altitude that might consume? perhaps something to test out...

Yeah, I suppose the "in-place" part is a little exaggerated. It's more like backing up a car, then once you're almost parked, changing your mind and driving away in the other direction.

I'd draw a picture, but Jimmy Pouchert would make fun of me.

Basically I get my canopy flying backwards, to the point where the pilot-chute is dangling over the front. I then let up one riser slowly, while pulling even more on the other side and shifting my weight to that side. This seems to put me in a banked turn flying backwards.

Edited to add: so yes, at this point you are still pulling both risers down, just one more than the other.

But again, maybe it only feels that way. The one thing I'm quite sure of is that it consumes a lot of altitude.

Cheers,

Jaap

 

I recall hearing from SabreDave that a certain very experienced paraglider pilot on your last foray together managed the sort of "helicopter spin" that's more typical of paragliding wings, but under a BASE canopy. I'm hoping to pick up this trick from said pilot over the summer; perhaps it might be worth your giving him a shout?

Yeah, we saw him do some stuff like that. Very cool. If you check out this video you can see that he definitely knows when to pull which risers. Pretty cool.

Cheers,

Jaap

Haven't tried it yet, but I've heard you grab both toggles- bury them fast (don't let canopy stall), then let one all the way up while keeping the other one down.

Sounds good.

Just remember, the more buttons you have to press, the more likely you will press them in the wrong order or miss something altogether.

While we are talking about trying manouvres,

There is a technique known as warping predominantly used in canopy formation base pin manouvres. It involves the use of one toggle and the opposite front riser. This one lets you keep a heading with minimal / no forward speed and minimal to no stall. Your descent rate does increase, but not as much as a rear riser stall.

You could do it with a rear riser and opposite front but it is less affective.

Not necessarliy for 180's but something that will teach you more about how those pesky canopies work.

 

A local experienced CReW dawg (that you know) taught me this last year as a way to fly with slow canopies in the skydiving environment. I haven't tried it with a BASE canopy (dang what am I waiting for). But it is a good technique once you can get past the canopy shuttering (not sure if that's a good way to describe the feeling of the canopy). Definitely something to try first in a safe place before you need to use it in sketchy situations. But I'm sure it can work with the right experience and practice. You've basically just created a shit load of drag while keeping the wing flying and flying slower yet still on heading.

Aaaahhhh I loved the sound of your post.

Whether my earlier post is full of shit or useful, you have opened your mind to possibilities. You are thinking outside the square.

A guy I used to jump with had that same philosophy. He became the best, and will probably remain so for a long time to come.

Just remember to risk manage all aspects of acting on your thoughts.

Stay Safe
Have Fun
Good Luck