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Looking Up at Deployment Time? (to minimise deceleration stress on body?)

 


mixedup  (D License)

May 29, 2013, 8:41 PM
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Looking Up at Deployment Time? (to minimise deceleration stress on body?) Can't Post

From the point of view of stresses on the body (neck in particular) is it best to look after deploying for a second or so to get the body to start to become vertical and help deal with deceleration? (i.e. before you then stop looking at the opening canopy and look out for canopy traffic)

Background:
* Now jumping with more people the standard practice is to not look at your canopy when it's opening, but rather be looking out for other canopies and getting ready on rear rises to take evasive action if necessary.
* So I've been doing this but I think I'm noting a bit more of the deceleration/whiplash effect & I'm thinking it's may be because I think I'm not looking up at all anymore when I deploy...


nigel99  (D 1)

May 29, 2013, 9:33 PM
Post #2 of 21 (3657 views)
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Re: [mixedup] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

mixedup wrote:
From the point of view of stresses on the body (neck in particular) is it best to look after deploying for a second or so to get the body to start to become vertical and help deal with deceleration? (i.e. before you then stop looking at the opening canopy and look out for canopy traffic)

Background:
* Now jumping with more people the standard practice is to not look at your canopy when it's opening, but rather be looking out for other canopies and getting ready on rear rises to take evasive action if necessary.
* So I've been doing this but I think I'm noting a bit more of the deceleration/whiplash effect & I'm thinking it's may be because I think I'm not looking up at all anymore when I deploy...

From protecting your neck, I would expect placing your chin on chest is the 'best' option and looking up at the canopy has got to be the worst.


obelixtim  (D 84)

May 30, 2013, 2:05 AM
Post #3 of 21 (3571 views)
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Re: [mixedup] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

 
Prepare to dodge some flak!!!.

I got shot full of holes when I suggested transiting to a head high position after pitching.

May be an idea to look at your packing if you are getting snappy openings.


mixedup  (D License)

May 30, 2013, 3:31 AM
Post #4 of 21 (3555 views)
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Re: [obelixtim] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

Actually remember where I heard advice re looking up. It was here (see below).

"Break-Away" Video which I have from the Skydiving Survival Series DVD (http://www.chutingstar.com/...-survival-series-dvd)

Quote:
T K Donle - Administrator of The Relative Workshop

...Throw it out into the airstream on your side, away from your body. As you look up to watch the opening continue to move your arms forward which will cause you to rotate head high. Thus the opening shock will be better absorbed by the harness system instead of your body...

John Sherman - Founder Jumpshack - Systems Designer

(re ensuring you are vertical as the parachute deploys)...accomplishing this manoeuvre is best done by gently looking up over the head, keeping the rotation in control & slightly ahead of the pull of the canopy. The shoulders must be kept level to prevent uneven line tension, the single biggest cause of canopy malfunction...


davelepka  (D 21448)

May 30, 2013, 4:10 AM
Post #5 of 21 (3530 views)
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Re: [mixedup] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

 
No offence, but you're getting 'mixed up'.

The reference to looking up are about right after you pitch your PC and the idea is to get your body pitched up head-high so your when your canopy sits you up, you're already half way there and will have less force pulling you upright.

This is why opening head low is generally so bad. to go from head low to sitting under canopy is greater than 90 degrees of 'sitting up' that your canopy has to pull you through. So if you're a little head high, it's less than 90 degrees.

Disclaimer - you are taking a risk in trying to sit up when you toss your PC. If you go too high you could flip over. If you have a PC in tow or hesitation, you could make more problems than you solve. The best bet is proper gear maintenance and packing, and remaining flat and stable during your PC toss, and let the canopy sit you up.

In terms of where to look during the opening, the talk about looking for traffic is during the snivel, after you have already been 'sat upright' by your canopy. At that time, when your canopy is sniveling and the slider coming down, the canopy is beginning to 'fly' and could be steered to some extent and at that time it's best to be looking for traffic.

Once the canopy sits you up, looking straight out and level is probably best. If there is any 'snap' to the inflation, your head will be centered over your spine and the weight will push straight down. If you are looking up at your canopy or have your head on your chest, the weight will be forced down and possibly extending your neck either forward or back. Even with your chin on your chest, it can slide further down and allow elongation injury, so avoid that one for sure.


tkhayes  (D 18764)

May 30, 2013, 4:15 AM
Post #6 of 21 (3522 views)
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Re: [mixedup] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

Sit up for the opening, as your pilot chute & bag are leaving, you should know what the timing of your opening shock is like - start to bring your knees down.

Ideally you end up in a sitting position when you hit the first bit of opening shock. The spine compresses vertically, which it is deigned to do and there is no whiplash.

The leg straps are on your thighs and you can even control some of the opening shock by lifting/lowering your knees, kind of a lever action.

Keep your hands out of the way of the risers/toggles, although some use their hands to gently spread the risers apart (high performance canopies)

Sitting up for opening is an old camera jumper thing when cameras were big and heavy, you sit up for the opening, grab your helmet/chin cup to stabilize your head through the opening.

Looking up not really advised, and laying there flat and just 'taking it' is not advised either, the spine gets quite a whiplash on a hard opening.


mixedup  (D License)

May 30, 2013, 4:20 AM
Post #7 of 21 (3516 views)
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Re: [tkhayes] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

thanks davelepka/tkhayes

I think we're all on the same wavelength. Maybe where I'm confusing things slightly is that I was assuming that you "look up" to start to get the rotation happening, but then ideally agree once you're near vertical for opening shock the head would be back to in line with your body...

So I think what you're suggesting is don't try to use a "look up with your head" method of starting the rotation, but use you legs moreso?

PS - tkhayes just noticed your avatar photo :) Looks a little scary. Hopefully wasn't hard opening related..


(This post was edited by mixedup on May 30, 2013, 4:22 AM)


tkhayes  (D 18764)

May 30, 2013, 4:31 AM
Post #8 of 21 (3504 views)
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Re: [mixedup] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

just sit - up, once the opening shock starts - your head should be level and simply ride it out. The only time I look is watching the pilot chute and bag deploy, and I am already bringing my knees down.


mixedup  (D License)

May 30, 2013, 4:34 AM
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Re: [tkhayes] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

cool - ok got it


popsjumper  (D 999999999)

May 30, 2013, 6:27 AM
Post #10 of 21 (3412 views)
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Re: [tkhayes] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

 
In reply to:
Ideally you end up in a sitting position when you hit the first bit of opening shock. The spine compresses vertically, which it is deigned to do and there is no whiplash.


So, the opening shock doesn't happen as expected, what now?
Am I in a freefly sit trying to work a problem?


DocPop  (C License)

May 30, 2013, 8:00 AM
Post #11 of 21 (3344 views)
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Re: [popsjumper] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

popsjumper wrote:

So, the opening shock doesn't happen as expected, what now?
Am I in a freefly sit trying to work a problem?

Now you're in the right position to deploy your reserve! Cool


popsjumper  (D 999999999)

May 30, 2013, 8:04 AM
Post #12 of 21 (3338 views)
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Re: [DocPop] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

DocPop wrote:
popsjumper wrote:

So, the opening shock doesn't happen as expected, what now?
Am I in a freefly sit trying to work a problem?

Now you're in the right position to deploy your reserve! Cool

Good thing I can sit fly....oh, wait....
LaughLaughTongue


rehmwa  (D 12816)

May 30, 2013, 8:06 AM
Post #13 of 21 (3337 views)
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Re: [] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

100% agree with TK's post on it.

start moving towards the 'sitting in the harness' orientation

as for the skull, I just try to keep my spine aligned and comfy so it doesn't whip if the opening is hard. so I hold my head staring straight ahead through the initial opening (until I know what kind of opening I'm getting).


cnsky54  (D 505)

May 30, 2013, 9:12 AM
Post #14 of 21 (3298 views)
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Re: [tkhayes] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

Long ago when learning to jump heavier cameras, JJ Johnson taught me to look at the horizon when chucking the PC, then to reach around and grab the camera helmet with both hands to stabilize it. Then, as the canopy opens and I am tipped upright, just keep focussed on the horizon until the bouncing stopped, and only then look up to see what kind of wing I had. Looking up or down is a bad configuration for the neck with the accumulating stresses at opening, and watching the horizon allows the neck to gradually straighten out as I was sat upright. It's been a pretty good lesson over the years. I cringe when I see others tip their heads back to film their openings and I imagine the shock going through a curved C1 to C6.Shocked


Sky_doggy  (C 41295)

May 30, 2013, 8:40 PM
Post #15 of 21 (3109 views)
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Re: [tkhayes] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

tkhayes wrote:
Sit up for the opening, as your pilot chute & bag are leaving, you should know what the timing of your opening shock is like - start to bring your knees down.

When I was just off student status I was jumping a rental Navigator 220. The thing was just a bloody mongrel. It wasn't all that old and I used to pay for it to be packed, but once in a while it would crack me. A couple of seasons back it cracked me so badly I couldn't jump for 2 weeks, actually I couldn't do much of anything for a while. After that I used to throw and then grab my head just waiting for it to spank me.

On reflection I think that holding my head might of induced problems but I am not sure. At about 50 jumps I bought a Pilot 188 and so far life has been good. I suppose any canopy can but bite but the Pilot/Pulse canopies seem to be less prone to this and I plan on jumping this style of canopy for a while.

I do have a couple of questions for the experienced people. Is moving your hands to hold your head while your canopy is deploying likely to just create a different set of issues.

Secondly, could someone explain more about opening in a sit?. Does this mean that you deploy in the normal belly to earth configuration and try to transition to more vertical position while your canopy is deploying?

Thanks


pchapman  (D 1014)

May 30, 2013, 8:50 PM
Post #16 of 21 (3101 views)
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Re: [Sky_doggy] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

Sky_doggy wrote:
Is moving your hands to hold your head while your canopy is deploying likely to just create a different set of issues.

On my Sabre 135, before adding a pocket to the slider, I would sometimes brace my head, by crossing my arms infront of my chin, hands at the opposite shoulder. Don't know if anyone else did something like that, but it helped me.

(Should be no problem to move hands around, assuming one is still stable for deployment. After all people also often reach up to put their hands near their rear risers on deployment.)


popsjumper  (D 999999999)

May 31, 2013, 6:53 PM
Post #17 of 21 (2964 views)
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Re: [Sky_doggy] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

 
In reply to:
Secondly, could someone explain more about opening in a sit?. Does this mean that you deploy in the normal belly to earth configuration and try to transition to more vertical position while your canopy is deploying?

Arrrrgh...this is what I was waiting for.

What they are talking about is NOT opening in a sit position. Your vertical speed is going to increase and that's NOT what you want to do here.

What they ARE talking about is at deployment, start bringing your knees in and down just so slightly to get an imbalance of air on your body....less on the legs while keeping a lot on your upper body. Just slightly, mind you.

This will start the rotation to head high, legs low. Ideally, you wouldn't want to be much more than at a 45 degree angle at inflation when you first start learning how to do this.

Now this is worrisome for young jumpers because some that are trying to learn this wind up over-rotating....not good.

So, when you start trying this out, only bring your knees in about 6 inches. Adjust a little at a time until you find that happy medium that is going to relieve a lot of pressure on your neck and back and at the same time keep you from over-rotating. We don't want to be doing back flips on opening.
Shocked

When the canopy is sniveling, you'll be rotated to a head-up vertical position. Now is when you can reach up to take up your risers.

Note: Some experienced people take up the risers as soon as they are available just prior to snivel start. I don't recommend that to young jumpers because you could adversely affect the opening by an imbalanced pull on the risers and/or a non-level body postition.


(This post was edited by popsjumper on May 31, 2013, 7:00 PM)


hypoxic_fool  (A 64188)

May 31, 2013, 7:35 PM
Post #18 of 21 (2946 views)
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Re: [mixedup] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

i have a sabre 1. i never watch my openings in fear of snapping my neck..


mixedup  (D License)

Jun 10, 2013, 8:33 PM
Post #19 of 21 (2660 views)
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Re: [popsjumper] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

popsjumper wrote:
start bringing your knees in and down just so slightly to get an imbalance of air on your body....less on the legs while keeping a lot on your upper body. Just slightly, mind you.
thanks popsjumper - just tried this recently and having more pleasant openings


Andy_Copland  (A 105852)

Jun 13, 2013, 11:31 PM
Post #20 of 21 (2303 views)
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Re: [mixedup] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

I have had two hard openings that really rocked my world and one ended up being a cutaway. In my experience, if you have time to look up, it's not a hard opening.


erdnarob  (D 364)

Jun 28, 2013, 1:32 PM
Post #21 of 21 (1878 views)
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Re: [mixedup] Looking Up at Deployment Time? (to minimise deceleration stress on body?) [In reply to] Can't Post

Don't look at your deployment with a fully elliptical canopy. That will change slightly your body in the harness and fully ellipticals are very sensitive even with a harness small change. It can start spinning because of that.
A good way to behave after having launched the pilot chute is to resume in a box position and look at the horizon. Don't worry, you will know soon enough that the canopy has deployed.Wink



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