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Guys/Gals,

I'm helping out on a very interesting project that may benefit us all and I have a question for the hardcore trackers out there. Let's just say you've jumped from a 1400' object wearing normal clothes and you opened low. How far "horizontally" from the exit point will you be when you're finally under canopy?

We are trying to determine how far a large pond should be from the exit point in order to save anyone who snivels in, pulls low (with partial canopy inflation), or has a line-over malfunction. Your data and/or comments would be greatly appreciated. Thanks.

I have no idea on how far people track,but would you build a pond from the toe of the object and all the way out?

I've really no scientific data by any means and don't even have a map handy to measure the distances, but I can give u some visual info about tracking in the swiss valley. Humming it in jeans and t-shirt going from LM I usually open over the landing (between treeline and street), going from YO I usually open just above treeline (both without doing aerials). Vertical is more than 1400 ft though if u track that far.

Pretty cool idea

Hey Jason,

So it sounds like either you have nothing specific in mind or you have an object in mind that can only be exited in one direction. It seems to me that this "safety pond" would have to be quite large to account for off-heading tracking, people who are more or less aggressive trackers, different types of clothing/suits, opening heading, etc. And then there are the people who are of the flat and stable mindset or aerialists.

With this in mind the "safety pond" should extend from the base of the object in a "V" shape extending to a distance equivalent to the distance the best tracker could fly until impact. Also, the depth should be about 2 feet with a clay base as was demonstrated by 736's Potato Incident; any deeper and he may have drowned before we could get to him, shallower and damage may have been much greater. If someone impacts vertically all bets are off anyway.

Given all this, you could look at the probabilities of the different types of accidents and adjust the pond proportionately. If the possibility of a full flight wingsuit to impact is extremely low and the cost of extending the pond that far is high you might consider making the pond shorter, however this happened at BD and the guy probably wouldn't be around had he landed on hard ground.

Good luck. It sounds like you may have something in mind that could be quite fun.

Tony

The design of the pond will accommodate the various exit points around the object. Hopefully, we'll be able to exit the North, South, and East sides of the object, so we'll put a large continuous pond directly below the exit points on those 3 sides. The big question is how far out should the pond extend? I'm getting some decent data so far, but could use more input. Wingsuits won't be considered for this object. I'm guessing that we'll need to extend at least 300' to be safe, maybe more. But we also want the bad trackers to be able to open their parachute and then make it over the water to land dry.

Also, realistically, what is a safe water depth for someone snivelling in or with a late deployment or line-over? Deep or shallow? I'm guessing deep since there will always be people around.

Thanks for the data so far.

exactly 731' 2". no farther, no closer. period.

The line length of the canopy.

If the canopy has reached line stretch, the canopy will hit the surface of the water and transfer the impact to the jumper via the harness. This is much better for the jumper than impacting the bottom and having the impact spread over a much smaller portion of their body.

Jason,
Are the ponds going to be so big and accommodating of the “average” fall rate so if you do open low you have no chance of getting land? I have class all day today but will go home tonight and pull up a google earth image and photo shop it to try to give some pretty decent rough estimations. Hopefully if will be helpful b/c the object I’m speaking of is 1500’, so pretty close anyway. Get a hold of T.J and Jimmy, they got a shit load of jumps of it over the past summer with wingsuits, regular clothes, and tracking suits. Also, what the hell is this about and where…..don’t leave us hanging.

BK

Edit: Didn't read your second post before I wrote this...so you answered part of it.

I really have to try hard to be able to go to the bottom of our pool when I jump from the 10 meter platform. The pool is 5 meters deep.
Taking into account that the jumper is never going to hit the water pure vertical (like cliff divers do), and that they have some canopy above their head, I would say that 3 meters would be enough.
I wouldn't make it less then two meters deep. You're not going to see me jumping from 5+ meters in a pool of only 2 meters deep.
Justing thinking...

Hey, is this pond going to be off an "A" or a "B" by any chance? If so think I can use it to land in?

Yes, probably classified as a B.

Ooooohhhhh!!!!!! Think the pond would end up being deep enough for me to land in?

500-600' with street clothes (normally tshirt & shorts) from 1550 pulling at 300. Take 150 off that height puts me at 600' horizontal pulling at 150 at your object, which would most likely be a snivel-impact.

I am a fat american though.

a GPS would be the best way to tell they have tham built into watches now

YO is almost exact 1400ft to the landing area.
with a good track in a phoenix fly suit i open in the middle between the treeline and the road.
measured from a map this is 700ft horizontal distance.
point of impact would be around 1000ft.....

Check out the low pull at waterfall in 96/97 vid on BE r.e. low pulls and water depth. It was pretty much a vertical entry from approx 850ft height. I would question 3m. Lets just say lines are 8 ft. Body from feet to risers are about 5 ft - that is 13 ft. Most entires will dissipate vertical distance travelled through water a/c body position / forward speed (horizontal velocity vector components), so they wont use the full 13. I do however remember on a few jumps taking a number of seconds to reach the surface after stopping descent.

Another reference would be the Douggs tracking vid from Smellveggen. You should be able to get some half decent time / distance data on that.

p.s. the other EASY way to check this is get a data logger and go for a leap out of a balloon / heli / plane / one of those motorised things!!!!

p.s.s - I can't track for shit - falling bag of shit technique is what I believe some people call it. That is why I made the ws all those years ago.

What is the horizontal distance to the Road on YO?

When not doing an aerial and just straight tracking I was opening at or slightly past the road (w/ PF pants and jacket). I was also able to make it to mid LZ after a triple tucked gainer. I was pulling significantly lower than the average jumper too though.

Coco

Correction: I only made it past the road on LM. I'm going to refer back to video but I swear I made it to the edge of the road on YO on one jump in particular. I'll see if I have any video of it.

Coco

I get about 150 feet horizontally exiting from 900 feet and opening around 150 feet. I would guess around 300 to 400 feet or so from 1500 feet.

You are just too rad. He who goes hard, doesn't usually go too long.

There were two or three threads a year ago or so with some hard data from Kjerag posted by Norwegians and included a few nice graphs:

http://www.dropzone.com/...post=1966908#1966908

 I can track all the way until I hit the ground

have a gowaylow day

according to GPS data and google, I know that on a no wind day and with normal cloths i reached about 465' horizonal from a little higher than this. And I wouldn't consider myself to be the best of trackers, but defintely not the worst! I also pulled at around 300' or a little higher.
Just pull before impact, and this might save you before the water.

From #7, Kjerag, with a running exit, I did 210m horizontal in 9secs with a running exit. Measured by GPS.
Hope this helps.
take care,
space
ps: This was a record back in the day.

nice one Paul

now coco can't believe it's just me giving him a hard time anymore...

here's some numbers for you coco:

18
35
39
42
47
49
51
56
59
62
64
68
69
70
75
77
78
80
82
83
85
86
87
89
91
93
102
103
105
108

what do they have in common?

some people may want to argue any one or several of them, but the way I see it, if they pulled higher (or at all) they all would've had a better chance of still being alive today


Coco: I am curious as to why you would want to be pulling significantly lower than the other jumpers?

Sounds like you meant that you did this regularly, not just by freak accident.

Are the other jumpers scared weiners who don't know the joy of the few seconds of freefall they are missing out on? Maybe they are just not as skilled and experienced as you and therefore need to pull higher for an equal margin of safety?

cya

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So would you be a below average jumper if you are pulling significantly lower ?

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