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downplaning - how, what and why?

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hi - i have been reading about 2 canopies out again. Downplaning is described as when the canopies dive toward the ground. Why/how would this occur? Does it mean it dives forward i.e. over your head, putting you into a pendulum position i.e. you are level horizontally with the horizon? Also, in the Perris Valley report on 2 canopies out, it says that some of the research, in the event of a down plane, recommended waiting for the canopies to bi-plane again instead of just cutting away the main.....however, how do you "wait" for a canopy/canopies to stop down planing, and what do you do to a canopy to stop it down planing and get it back into an above your head configuration?
Thanks for the help people

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That is interesting, wait/hope for the canopies to go back into a biplane. If the canopies are clear of entanglement, you are sure there are no lines, or any portion of the canopy entangled, my advice would be to cut away the main. What if the two never went back into a biplane? Have you ever witnessed a "ground plane"? Not pretty.

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Downplaning occurs when you fart under canopy. The burble that your fart creates tricks the cypres into thinking that your in trouble and it fires your reserve. Now you have two canopies out above you in a biplane, while behind you the "fart wash" creates turbulance under the canopies, thus causing them to dive away from each other, creating a down plane. To get them back into a biplane, you have to reverse the problem by burping, which creates a "belch wash" in front of you, which creates a low pressure zone above you, which sucks the canopies back up over your head in a biplane.
Just take "Gas-X" before you jump and you should be okay.
"I live to EFS"
Tom

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Downplaning occurs when you fart under canopy. The burble that your fart creates tricks the cypres into thinking that your in trouble and it fires your reserve. Now you have two canopies out above you in a biplane, while behind you the "fart wash" creates turbulance under the canopies, thus causing them to dive away from each other, creating a down plane. To get them back into a biplane, you have to reverse the problem by burping, which creates a "belch wash" in front of you, which creates a low pressure zone above you, which sucks the canopies back up over your head in a biplane.
Just take "Gas-X" before you jump and you should be okay.
"I live to EFS"
Tom


Thanks for clearing that up for us Tom!:)

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Re: "I don't think this is the forum for an answer like this, funny though it is. Put that sort of thing in Skydiving Talkback and leave this forum for serious discussion, lest HH have your head."
Hey, I take offense to that......alot of time and effort went into my reply....LOL
"I live to EFS"
Tom

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You can't survive a biplane config. at minimun altitude the only option you have is cutaway

This deserves a response, unless it was a troll.
A downplane is not survivable. I've never heard the advice to wait for it to "go away", and I don't think I'd want to. To me, downplane means cutaway immediately.
However, the other 2-out situations (bi-plane and side-by-side), will be landable under most circumstances. Iirc, the suggestion is to leave the brakes stowed, and stear the dominant canopy with light rear riser input. Prepare to PLF, and don't flare.
I'm still a newbie to this sport, so some of those details might be off a bit. But it's certainly not true that your only choice in a biplane is to cutaway.

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I saw someone land under a downplane...and the person is still alive...so yes a downplane is survivable.....now I'd like to say it was my prompt emergency medical care at the scene that helped him...BUT...it was alot of factors stacked in this chicks favor....like a nice FL thunderstorm and hour earlier...and landing in a giant puddle.....so dont say it is NOT survivable...by the way she did bust her self up real good....
Cheers....vasbyt
marc
"I have no fear of falling, I just hate hitting the ground"-The Badlees...

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We had to send some of our club's expert cypreses off for their 4-year check recently. A few jumpers felt uncomfortable jumping without a cypres so we moved one of the student cypreses out of a J7 currently not being used into a J3 with a Pro 170 that several jumpers use. Last weekend one of our members performed a 360 front riser turn...which managed to fire the cypres at about 600 feet AGL. Several jumpers who witnessed the event said the 2 canopies were heading for a downplane quickly. Luckily for him he saw the lines were clear and knew to cut away the main quickly. He landed the reserve and was just fine. Definitely made for an interesting situation.

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I was taught that if the two are clear of each other, cut it away, ie. downplane and possibly side by side
As a side note, SHOULDN'T this be an instance where you want to get the RSL disconnected before cutting away?
Conjunction Junction, what's your function?

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>hi - i have been reading about 2 canopies out again. Downplaning is described as
> when the canopies dive toward the ground. Why/how would this occur?
The second canopy swings "beneath" you. The two canopies both generate lift, but now the lift cancels itself out, and you head straight down, slowed down only by the canopy's drag.
>Also, in the Perris Valley report on 2 canopies out, it says that some of the
> research, in the event of a down plane, recommended waiting for the canopies to
> bi-plane again instead of just cutting away the main.....
I don't recommend this. If you are downplaning:
1. you probably won't survive the landing
2. you are in a good position to cut away
Seems like an easy decision.
-bill von

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First off, a downplane can be survivable. It depends on the sizes of the canopies involved. I have seen a Manta/Raven 4 downplane into the ground with non-life threatening injuries.
The side by side and biplane situations are landable.
Danger

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>As a side note, SHOULDN'T this be an instance where you want to get the RSL
> disconnected before cutting away?
Wouldn't hurt, but isn't that important. Keep in mind that it's not going to do anything. The only reason to consider it is to remove another potential snag point on the cutaway main, which is an issue especially if it's _not_ in a downplane (i.e. will have to pass by the main.)
-bill von

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I'm currently considering buying a new rig, and was wondering about the two-canopy situations: How well can a highly loaded cross-braced elliptical main and an almost-as-highly loaded low-aspect-ratio F111-reserve fly? Say, a Velocity103 and a Tempo120? (the Velocity loaded at 1.9). I'm inclined to think that a combination such as this may not be landable, especially in a side-by-side configuration. Any thoughts on this?

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at minimun altitude the only option you have is cutaway

What is the minimun altitude for this? Surely you'd want to cut away even very low because with a downplane you're going straight down, whereas after yuo chop, you'll get horizontal speed with which you could flare?
When you participate in sporting events, its not whether you win or you're loose, its how drunk you get.

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You can survive a downplane. I can give you 3 names if you want. one was a 2 canopy out situation. The guy kinda landed on the edge of trees and walked away.
The other 2 were doing a CReW downplane and their leg lock jammed. they both "landed" the downplane (or should I say the dowplane landed them) on the runway (tarmac). They both are still very alive, one of them has permanent leg damage, the other, you'd never know he came that close to the reaper...
That being said, I dont think any of them would recommend landing a downplane!
Remster
Muff 914

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Re: "A guy asks a serious question that could save his life and you respond with that!"
Jeez, where's your sense of humor? LOL Just kidding. In all serious though, I know this is a safet and training board, but really, a question like that should only be answered by newbie's aff instructor. For any of us to cloud the answer with our opinions, fact or not, will inevitably lead to confusion should a real crisis situation ever actually occur to this jumper. Newbie's aff instructor should be the only one answering this question for him or her. That's my view. My answer, while not accurate, most certainly will not be interpretted as fact and subsequently confuse newbie in an emergency.
"I live to EFS"
Tom

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>I know this is a safet and training board, but really, a question like that should
> only be answered by newbie's aff instructor.
While I agree that a new jumper should only heed the instructions of his JM, I don't think there's anything wrong with answering it. This board gets read by everyone from pre-FJC students to experienced jumpers, and often the people who learn the most didn't ask the original question.
I used to add a disclaimer every time I answered someone who I suspected might be a student (to the effect of "your instructor has the final say.") Maybe we should be careful to do that in the future if we suspect we're talking to students.
-bill von

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>As a side note, SHOULDN'T this be an instance where you want to get the RSL
> disconnected before cutting away?
Wouldn't hurt, but isn't that important. Keep in mind that it's not going to do anything. The only reason to consider it is to remove another
potential snag point on the cutaway main, which is an issue especially if it's _not_ in a downplane (i.e. will have to pass by the main.)


My guess is that on double-sided RSL's (ie Racer) you would need to disconnest them...I think you might run the risk of choking off your reserve if you don't. It's probably something worth checking on your rigs to figure out if you need to do it or not.

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