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Hypothetical.... Your under canopy....

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Hypothetical.. Your under canopy and discover a tension knot in one of your steering lines. When you release the breaks you get thrown into a hard spin. You are unable to release the tension knot by trying to stall the canopy. The next option would be to cut away and deploy your reserve. My question is could you instead use your hook knife and cut both of your steering lines and then land using rear risers. Would the canopy still be air worthy with both steering lines cut?

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Go to your DZ and ask your instructor about in air rigging.

Me, I have a very good rigger and I think I will leave the rigging to him and go to my reserve as my only option.

Now if that shit happened on my reserve then I better get to cuttin'

MAKE EVERY DAY COUNT
Life is Short and we never know how long we are going to have. We must live life to the fullest EVERY DAY. Everything we do should have a greater purpose.

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You are unable to release the tension knot by trying to stall the canopy.



Could you just clarify that bit? I'm interested in what you understand to be the procedure for attempting to release a tension knot.
Do you want to have an ideagasm?

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Hypothetical.. Your under canopy and discover a tension knot in one of your steering lines. When you release the breaks you get thrown into a hard spin. You are unable to release the tension knot by trying to stall the canopy. The next option would be to cut away and deploy your reserve. My question is could you instead use your hook knife and cut both of your steering lines and then land using rear risers. Would the canopy still be air worthy with both steering lines cut?



Can a canopy landed without steering lines?

Yes it can, it is normally a procedure that takes some practice up high. It is possible to stall the canopy on landing and you can hurt yourself.

Can you cut the steering lines on a diving spining canopy?

Hypothetically sure, why not.

You can also end up spending way too much altitude fixated on the problem, trying to get out your hook knife, and then pull the steering line away from the other lines in order to cut it.

You may spin in all the way to the ground trying to do this and die.

You may realize way too late that this was a bonehead idea, cut away, and crater in before you get a fully inflated reserve over your head.

You might even get both lines cut, just before landing. Not having practiced your rear riser landings you might stall out 15 feet from the ground, land on your back, and end up in a wheel chair.

Hypothetically you could even cut away and have a reserve malfunction.

Stick to your emergency procedures.
"The restraining order says you're only allowed to touch me in freefall"
=P

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Your idea would work on most seven cells and would be something to keep in mind if it happened on your reserve. But some 9-cell canopies might start bucking if you cut both control lines.

Another thing to keep in mind is how sharp hook knives are and how easy things are to slice through when they are under tension. If you go at it in a panicky way it's possible to slice more lines then you meant to, and even cut through a riser if you're really flailing . . .

On the rear riser landing, if not experienced with it, what you want to do is forget about "landing" in the normal sense. You just want to keep yourself obstacle free, into the wind, and slow yourself down enough to "slide yourself in," while keeping your legs together and your arms in. Think baseball and you're stealing second base . . .

The mistake most make is not realizing a little riser equals a lot of toggle. If you haul in on the risers like you might with the toggles there's a big chance of stalling and then dropping straight in.

Somebody here has a good sig line that goes something like, "Your chances of survival depend on your angle of arrival." So in this case think shallow . . .

NickD :)

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I don't see it working. Typically, doesn't a rear riser flare have some affect on the trailing edge through the steering that are being pulled down along with the risers. When you cut the steering lines your rear riser flare will no longer have any affect to the trailing edge of the canopy. It's cool you carry a hook knife though...

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I don't see it working. Typically, doesn't a rear riser flare have some affect on the trailing edge through the steering that are being pulled down along with the risers. When you cut the steering lines your rear riser flare will no longer have any affect to the trailing edge of the canopy. It's cool you carry a hook knife though...



Yes, but you have your D lines that attach to the trailing edge. Those lines can be accessed through your rear risers. you would think you could generate ample flare across the trailing edge with those suspension lines by pulling your rear risers even if your cascading steering lines were non existent.

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First, you're thinking and asking good questions, so that's a good thing. As a student, and going on as a newbie, you've pretty much been told to cutaway anything that's not there, square, or responding to a controllability check. A lot of newbies do cutaway from situations that a more experienced jumper MIGHT be able to land safely. And unless you have an obvious, horrifying high spped malfunction, there's always some asshole on the dropzone who will give you a load of crap about not having to cutaway from it (fuck them, it's YOUR life).

Rear riser flares are something to practice up high. Most canopy courses will teach you a few things about rear riser flaring and even intentionally stalling and recovering with your risers (up high of course).

But you can waste a lot of time and wreak a lot of havoc with hooknife and then you have a main canopy you can't jump again until it's been repaired in a rigger's loft. You've got handles and a reserve for a reason. Use 'em and cutaway. Land under a good controllable reserve. Don't get scared into sticking with a bad canopy and don't try to earn your rigger's ticket under a canopy you can't control.

Experience is no guarantee either. We just lost an experienced swooper this summer who had over 2000 jumps. His problem wasn't with steering lines, but he knew things were wrong above 2 grand. He decided he could land it and his mistake cost him his life. Cutting away might have embarrassed him and might have eliminated him from the meet he was jumping in, but stacked up against losing his life, it would've been nothing.

Your humble servant.....Professor Gravity !

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Thanks for all the input. I had this malfunction a couple of weeks ago. I noticed the tension knot right after full canopy inflation. When I released the brakes I was thrown into I violent spin. I chopped it and deployed my reserve, and all was well. I was laying in bed last night thinking about the malfunction and anything else I could have done. Given the same situation I would probably chop it again, but if there are other options I want to know about them.

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Hypothetical.. Your under canopy and discover a tension knot in one of your steering lines. When you release the breaks you get thrown into a hard spin. You are unable to release the tension knot by trying to stall the canopy. The next option would be to cut away and deploy your reserve. My question is could you instead use your hook knife and cut both of your steering lines and then land using rear risers. Would the canopy still be air worthy with both steering lines cut?



You could, but your canopy is going to stall much more abruptly on the rear risers. Most people don't have a lot (any) rear riser landings and will be a lot less likely to injure themselves on their reserve with intact steering lines.

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No, it works without the control lines. Many B.A.S.E. jumpers have mechanically released their control lines after lines overs and steered and landed fine with just the rear risers . . .

NickD :)



Most BASE jumpers with the potential for visiting interesting landing areas are jumping wingloadings under .7 pounds/square foot. After some time in the sport lots upsize.

The skydivers who listen to Brian Germain's "conservative" advice start with canopies which land with 140% of the energy they'd have at BASE wingloadings. After some time in the sport lots downsize, with experienced jumpers having 250%+ of BASE landing energy.

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>Would the canopy still be air worthy with both steering lines cut?

Some yes, some no. At Bridge Day you get to see all sorts of bizarre rigging combinations. I recall one 7-cell (forget the make) that had a line-release mod and no slider. Jumper exited, released both brakes, dropped them both - and the canopy folded upwards at the tail. She landed in the water without injury but likely would have been injured had she landed on the ground.

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Yes, but you have your D lines that attach to the trailing edge. Those lines can be accessed through your rear risers. you would think you could generate ample flare across the trailing edge with those suspension lines by pulling your rear risers even if your cascading steering lines were non existent.



No.

Your steering lines are attached to the outside of the canopy's trailing edge. The amount of canopy distortion is intentionally limited - one company switched from 5 brake lines to 4 when customers were stalling too easily. Pulling on them works a bit like flaps on a plane which give you more lift and more drag. The added drag slows down the canopy, the jumper continues to travel forwards, and the whole system pitches as the jumper moves thus gradually changing the angle of attack (the angle between the canopy and relative wind).

Your D-lines are attached some distance forwards of the trailing edge nearly always to the same risers as the C-lines. Pulling on the rear risers directly changes the angle of attack so the effect is immediate. There's not much distance between where the front and rear risers attach to the canopy (you're looking at the average of the A/B line attachments to the C/D average) so it doesn't take much.

The canopy stalls when the angle of attack becomes too large causing the airflow over its top surface to separate from the canopy. This happens regardless of speed.

So the risk here is that relatively little input will stall the canopy relatively quickly when it still has significant forwards and vertical speed.

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Your under canopy and discover a tension knot in one of your steering lines. When you release the breaks you get thrown into a hard spin.



This wasn't hypothetical for me. I had exactly this happen once when I had about your number of jumps.

All I did was hold the unaffected toggle in half brakes and fly back to the DZ. Just made it on, one braked turn for landing and a flare from half brakes. Landing was a little heavy but nothing to be concerned about.

Just resort to student training. Is it big/square/controllable? Answer: yes, yes and
Well... can I control it? – yes! Right hand control line is stuck. But my left hand control line gives me all axis of control. Half brakes for straight ahead. Full brakes for left. No brakes for right. A practice flare appreciably slows and alters the angle of decent. Test passed!

So long as your canopy is of a size where a landing from half brakes isn't going to cause injury, this is potentially little more than a minor inconvenience. If your canopy passes a control test, there's not really anything to indicate a need to cutaway or start slicing lines.

Now if the control test cannot be passed... well, the rest of the thread covers that situation.

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I had this malfunction a couple of weeks ago. I noticed the tension knot right after full canopy inflation. When I released the brakes I was thrown into I violent spin. I chopped it and deployed my reserve, and all was well. The canopy definitely did not pass its controllability test. It was one of the hardest spins id been in. Hard enough to make it difficult to reach my handles do to centrifugal force. I have been thinking about the malfunction quite often and that’s why I presented the hypothetical in regards to cutting the steering lines. Just thinking of other possibilities.

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I had this malfunction a couple of weeks ago. I noticed the tension knot right after full canopy inflation. When I released the brakes I was thrown into I violent spin. I chopped it and deployed my reserve, and all was well. The canopy definitely did not pass its controllability test. It was one of the hardest spins id been in. Hard enough to make it difficult to reach my handles do to centrifugal force. I have been thinking about the malfunction quite often and that’s why I presented the hypothetical in regards to cutting the steering lines. Just thinking of other possibilities.


You did the right thing. It's not worth trying to figure out any other way.


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If this happened to my reserve, that's what I'll have to do -- parachutes don't need steering lines to land themselves, rear riser flare practice is handy, but I'm not going to play with a hook knife while a main canopy is spinning me like a malfunctioning amusement park ride... I'm convinced by reading about people running out of time under spinning canopies.

I had one experience where one toggle was stuck (it resolved itself), but if this happened again and I was unable to fix this next time: I MIGHT re-stow the other toggle as long as I'm flying straight. It's doable because I had both of my two hands free to attempt that. I would probably give myself about 5 to 10 seconds max to do this (flying straight, slow half-brakes descent -- so not a high speed malfunction) then land using my rear risers. Mind you, this is not the same situation as yours (jammed toggle rather than a tension knot, and I could easily stop my canopy from turning)

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Just resort to student training. Is it big/square/controllable? Answer: yes, yes and
Well... can I control it? – yes! Right hand control line is stuck. But my left hand control line gives me all axis of control. Half brakes for straight ahead. Full brakes for left. No brakes for right. A practice flare appreciably slows and alters the angle of decent. Test passed!


That might be what I do too in that exact situation even without knowing about this thread (fully controllable with modified control input), but I would definitely do several VERY aggressive flare tests to make sure the tension knot was tight enough that it wasn't going to slip by accident and suddenly hook me to the ground. Then below harddeck, I'd be gentle, just to be safe.

People have been hurt by a tension knot suddenly becoming undone during a flare, causing the canopy to hook into the ground.... There was an actual thread about somebody getting hurt with this....

So this isn't a controversy-free emergency procedure. :S:o
One not generally recommended by instructors for new jumpers, for sure...

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Thanks for all the input. I had this malfunction a couple of weeks ago. I noticed the tension knot right after full canopy inflation. When I released the brakes I was thrown into I violent spin. I chopped it and deployed my reserve, and all was well. I was laying in bed last night thinking about the malfunction and anything else I could have done. Given the same situation I would probably chop it again, but if there are other options I want to know about them.



A violent spin will reduce height fast. So during this spin you want to spend time to find your hook knife, select the correct lines (I hope you are sure it is the steering line) Cut both lines. After that you have to land a canopy using an unfamilliar method perhaps even an off DZ landing

OR

Cut away, pull reserve and very likely more time to plan your landing using a method (toggles) you are familiar to.

Unless you are a highly skilled current canopy expert, the first option looks like an ticket to the local hospital or worse. In case you are a highly skilled canopy expert you should know the answer.
Using your droque to gain stability is a bad habid.
.
.
Also in case you jump a sport rig!!!

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Can a canopy landed without steering lines?

Yes it can, it is normally a procedure that takes some practice up high. It is possible to stall the canopy on landing and you can hurt yourself.
......
Not having practiced your rear riser landings you might stall out 15 feet from the ground, land on your back, and end up in a wheel chair.
......
Stick to your emergency procedures.



Good stuff, DougH.
To emphasize for the OP because it's worth repeating.

You can land your canopy on rears, yes. Attempting to do so without knowing where that rear-riser stall point is exposes you to a major danger of injury. So here's what you do...

Practice your rear risers up high. In clear airspace, watch your canopy and pull the risers 3 inches and hold for a couple of seconds to see what happens...get a feel for how the canopy planes out with rears. Let them back up gently and repeat the process pulling them 3 more inches and then 3 more, etc. UP TO THE POINT of seeing and feeling the canopy start to flutter. That fluttering gives you a warning that you are approaching the stall point. It also shows you the point which you DO NOT WANT TO EXCEED when you attempt to land on rears. Pulling the risers more than that will stall the canopy...you really do NOT want to do that on landing.

If you, up high, actually stall the canopy, just simply let the risers back up gently...try to avoid the first-stall panic screaming like a school girl.
:D

Please note: This helpful hint may not apply to HP canopies as I have no experience with the hot rods. I fly and teach only trucks and sedans.
My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239

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Hard deck-Know it before you get on a plane and stick to it. For me 1500 feet not floating happily means EP no matter what. I hope to stick to this for all my jumping life. I think that’s one of most important rules I learned. # 1 priority don’t go below the hard deck with any mal. Unless of course you have a double mal.


A lot more qualified people have already spoken this is just my .02
I'd rather be hated for who I am, than loved for who I am not." - Kurt Cobain

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