What to do in a canopy collision?

[Lolie 0]

I've heard before that if you can't avoid someone else's canopy, you should spread your body out to avoid going through their lines. I read this weekend (in the Skydiver's Survival Guide), though, that Microline can act like a cheese slicer at too high of a rate (gross imagery, but it gets the point across), and that you should think about making yourself as thin as possible. Is that the generally accepted concensus?
btw-I really like the Skydiver's Survival Guide. I recommend it to everyone just off student status. Or anyone else, for that matter.

-Miranda
you shall above all things be glad and young / For if you're young,whatever life you wear
it will become you;and if you are glad / whatever's living will yourself become.

[AggieDave 6]

I really don't see any reason why you should have to get to this point, that if you have a second to decide to get big, you should have that second to grab a riser and get away.

Yes, microline can do that and its even more dangerous under a higher wingloading.

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

[Lolie 0]

That was definitely my first impression, too. I guess maybe if you're physically injured to the point where you didn't have any other option (i.e. something completely extreme like dislocating both shoulders?)? IMHO, people shouldn't be finding themselves in situations where they need to make that sort of decision.

-Miranda
you shall above all things be glad and young / For if you're young,whatever life you wear
it will become you;and if you are glad / whatever's living will yourself become.

[geanky 0]

This would be a good question to ask the CReW dogs...try posting in the canopy relative work forum.

learn to fly in 3d

[Luminous 0]

Quote

if you have a second to decide to get big, you should have that second to grab a riser and get away

in that second you may be able to grab the riser, but can you pull it and have the canopy react fast enough to avoid the collision?
Her question deals with the "collision now unavoidable" scenario, in which case I was originally taught to get big to avoid passing through the lines, but with the now commen use of micro line, it's best to just try to go through the lines without getting sliced up.
BSBD

'In an insane society a sane person seems insane.' Mr. Spock

[billvon 3,072]

>that Microline can act like a cheese slicer at too high of a rate

There are two issues. One, microline can injure you because of its small diameter, and two, microlined canopies go much faster, thus making injury more likely.

>I really don't see any reason why you should have to get to this
> point, that if you have a second to decide to get big, you should
> have that second to grab a riser and get away.

Two canopies going 25mph have a closing speed of 75fps. If you get distracted, look down, and look back when the canopy is 50 feet away, you have much less than a second to grab a riser or toggle and turn away. In addition, your canopy does not turn instantly, and if you turn the wrong way you can increase the odds of hitting the other guy - so you really don't have as much time as you think you do.

In addition, there are cases where your options are a collision or a toggle turn at 50 feet. If you can't flat turn, a collision is the more survivable option.

[DJL 235]

Damn, this isn't talkback, otherwise I'd just spout about how more people should jump with samurai swords and chop anyone who gets close.

Oh well, check out:
crw paper and Advanced Canopy Course to read up on how crw-dogs handle wraps and entanglements. Also, do a search on here for the same.
I think the biggest thing you'll learn is that a low level collision is something you want to avoid. Low timers like you and I are pulling higher and flying circus tents so we have a little bit more time to think about how we want to enter the pattern. When you open, pay attention to who is above you and who is below you. Look before you turn and don't assume a more experienced jumper will make the right move. It's your ass so make the decisions. If there's traffic, land away from the peas.

-Doug

"I encourage all awesome dangerous behavior." - Jeffro Fincher

[quade 4]

Quote

This would be a good question to ask the CReW dogs...try posting in the canopy relative work forum.

Actually, this is an excellent question for anybody that jumps when there's more than zero other people in the sky.

A canopy collision during CReW is one thing and yeah, that would suck, but what sucks even worse is a head-on collision on opening or near the ground. Both scenarios have killed a number of folks over the years.

quade -
The World's Most Boring Skydiver

[Lolie 0]

So Plan A would be to turn away (obviously), but if you're too low or too close, Plan B would be to get small and hope for the best.

-Miranda
you shall above all things be glad and young / For if you're young,whatever life you wear
it will become you;and if you are glad / whatever's living will yourself become.

[Jimbo 0]

Quote

Plan B would be to get small and hope for the best.

I thought that plan B was to get BIG and hope for the best? Did I miss something?

-
Jim

"Like" - The modern day comma
Good bye, my friends. You are missed.

[billvon 3,072]

>I thought that plan B was to get BIG and hope for the best? Did I
> miss something?

Depends on the canopy. On slow canopies with dacron lines (i.e. student or CRW canopies) getting big is generally considered a good idea. With smaller/microline canopies, getting small so you go through the other canopy (and can cut away cleanly) is generally a better idea. Neither one works as well in practice as it sounds like it does, of course - you don't really just bounce off someone's lines and go happily flying away in the opposite direction, nor is going through someone's lines likely to be clean and painless. But the above guidelines can at least increase your chances of landing alive and in one piece.

[DJL 235]

Sounds a bit like going into trees.

I haven't been in any wraps or entanglements but this is my line of thinking when doing crw (only about 15 jumps and no big stuff). If it starts to wrap then get your elbows over your handles and your palms on your chin so you can pull lines from around your neck. Keep your feet together so that both feet are wrapped instead of just one. In this postion you'll be able to use both legs instead of just one and can spread your legs apart to make slack or pull the lines within range on your hands, your arms are also in the best position to push lines away from a midsection wrap. Mr. Microlines has probably already chopped so you're left to deal with two canopies around your body. Read the literature from there on.

-Doug

"I encourage all awesome dangerous behavior." - Jeffro Fincher

[faulknerwn 38]

If its a CRW wrap and a slow-speed collision with dacron lines, getting big is definitely the better option. If I'm going to hit microlines, I'm getting small and covering my face/handles with my arms.

I was involved in a head-on collision post-CRW wrap about a year and a half ago.. I hit dacron lines, but we had a closing speed of ~70mph. I remember covering my face and I did a half twist. Had lots of line burns on the back of my body, and still have a nice scar on the back of my knee. Microlines very possibly could have sliced my leg off. I'm definitely a believer in getting small.

W

[jurgencamps 0]

Getting big was the best thing you could do when you were jumping a round canopy.

[bobsoutar 0]

I do a fair amount of CRW and if a canopy is going to hit me from any angle I spread arms and legs wide.
Microlines are nasty whatever you do. They are likely to be nastier if they are wrapped around you with the weight of another jumper underneath than hitting you in the first place. In a microline wrap situation (assuming sufficient altitude) the person who has wrapped you up should cutaway immediately.

[miked10270 0]

Hi there,

My own belief is to GO BIG REGARDLESS!! Even with Microlines. The reason for this is twofold:

1. I don't want a canopy collision to become a wrap - there's more chance of finding yourself free with a spread position 'cos there's more chance of bouncing / sliding off.

2. No matter how small you try to make yourself, if your body is going to hit lines, then you're likely to hit at least one or two lines... Now consider those guys who lie on beds of nails - one nail would go through them, but because they're lying in hundreds then the pressure from each individual nail isn't enough to penetrate their skin! If you spread the collision pressure then you'll reduce the seriousness of the damage in each area? While one microline may well act like a cheese wire, absorbing the pressure of five or six hit simultaneously should make for far less serious injuries - do you want a half dozen minor injuries or one really serious injury?

Regards,

Mike D10270.

Taking the piss out of the FrenchAmericans since before it was fashionable.

Prenait la pisse hors du FrançaisCanadiens méridionaux puisqu'avant lui à la mode.

[bobsoutar 0]

My own belief is to GO BIG REGARDLESS!! Even with Microlines.
Hi Mike
1) Thought that was what I said! Also that if (despite spreading arms and legs wide) you still end up wrapped up in microlines, the other pilot should cut away immediately to take the weight off the lines.
2) Don't want either thanks - you'd better get onto that cutaway handle before I get to my hook knife!!!
Blooos

[Cornholio 0]

Quote

1) Thought that was what I said! Also that if (despite spreading arms and legs wide) you still end up wrapped up in microlines, the other pilot should cut away immediately to take the weight off the lines.

Hmm...I was under the impression that if two people are involved in a wrap, that the lower person should NOT cut away because it could wrap the top guy up more. The bottom guy should stay put until the top guy frees himself or he cuts away. Either way, they should both be talking to each other before the bottom guy cuts away unexpectedly. Keeping weight on the lines is what is needed so they top guy can easily free himself. If the bottom guy cuts away, it's more of a mess to get tangled up with the top guy.

Butthead: Whoa! Burritos for breakfast!
Beavis: Yeah! Yeah! Cool!
bellyflier on the dz.com hybrid record jump

[PhreeZone 20]

With Dacron thats true... but micro line is a new ball game. I'm not sure what to do, but i know micro line under tension is more then enough to cut to the bone on your leg.

Yesterday is history
And tomorrow is a mystery

Parachutemanuals.com

[Sonic 0]

The way I see it, the bottom guy should chop in a wrap, as he can cleanly cut away and deploy a reserve - the top guy still has a fully functional canopy and therefore has a little time to sort it out. Also, if the bottom guy is still hanging, he is putting tension on the lines that could be around your neck - not good

-----------------------------------
It's like something out of that twilighty show about that zone

[Cajones 0]

It's all about communication. In a "normal" CRW wrap, it's not a simple "bottom guy cuts away." All canopy wraps aren't a top/bottom. All wraps aren't the top guy wrapped in the bottom guys parachute with the bottom person dangling below. The are very few cut and dried rules when it comes to a wrap. Communication between both jumpers is the key. Where's our CRW moderator when you need her???

The laws of physics are strictly enforced.

[billvon 3,072]

>I don't want a canopy collision to become a wrap - there's more
> chance of finding yourself free with a spread position 'cos there's
> more chance of bouncing / sliding off.

I honestly don't think that a collision between two canopies, both with microlines, closing at 40mph, will result in one canopy "bouncing off" the other and heading safely away. I have never even heard of this happening, and is difficult to picture in terms of the physics of the event.

>No matter how small you try to make yourself, if your body is going
> to hit lines, then you're likely to hit at least one or two lines... Now
> consider those guys who lie on beds of nails - one nail would go
> through them, but because they're lying in hundreds then the
> pressure from each individual nail isn't enough to penetrate their
> skin! If you spread the collision pressure then you'll reduce the
> seriousness of the damage in each area?

Right, but consider a PLF. It protects your spine, chest and skull at the possible expense of your legs and feet. No one advocates hitting the ground face first in a spread eagle to 'spread the impact.' If you do collide with a canopy, where do you want a 3-cm deep gash - in the back of your arm or your throat?

Microlined canopies are small and generally fast. You are going to experience injury or gear damage if a line runs across you; hoping that you hit many lines with zero relative speed (at least up and down relative to the line) might not be realistic. Balling up can reduce the number of injuries, reduce the chance a line will catch or cut your handles or harness, and protect your belly, chest, face and neck (at the expense of your arms and shins, of course.)

[ernokaikkonen 0]

>I was under the impression that if two people are involved
>in a wrap, that the lower person should NOT cut away because
>it could wrap the top guy up more. The bottom guy should stay
>put until the top guy frees himself or he cuts away

I only have around 10 CF-jumps, but this is not what I remember from the briefings. Think about it! If the top guy, with a functioning parachute, cuts away and falls on the bottom guy, is that going to improve the situation?

What I have been told is that the jumpers should attempt to communicate about the situation, and if the bottom jumper can't get an answer out of the top jumper, the bottom guy should cutaway(since the reason the top guy didn't answer could be the lines around his neck choking him).

Jussi are you lurking? Did I get it about right? (it's been over a year since my last CF jump...)

[bobsoutar 0]

In CRW there are various different situations requiring different procedures - line entanglements are not dealt with in the same way as canopy wraps for instance.
A collision between 2 jumpers using canopies with microlines is another ball game. A guy tangled up in the other jumpers lines needs the pressure taken off immediately and can't risk cutting away while still caught up in them.

[faulknerwn 38]

Quote

Hmm...I was under the impression that if two people are involved in a wrap, that the lower person should NOT cut away because it could wrap the top guy up more. The bottom guy should stay put until the top guy frees himself or he cuts away. Either way, they should both be talking to each other before the bottom guy cuts away unexpectedly. Keeping weight on the lines is what is needed so they top guy can easily free himself. If the bottom guy cuts away, it's more of a mess to get tangled up with the top guy.

You're think of an entanglement not a wrap - that's a different beast. There's a paper on this on my website - good reading for this thread.

CRW Paper