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object seperation
Does anyone know how much seperation the average jumper gets from an object with a hard launch, standing and running, at variouse subterminal delays?

I know it's going to vary largely depending on jumper, but I was wondering if anyone has some rough numbers, or if there is a way to calculate this based on how far the jumper can jump at ground level.
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Re: [hikeat] object seperation
factors are infinite.

assuming a vertical object, (no overhang on exit, etc,
assuming the jumper is not using aerodynamics to gain distance, (tracking)
assuming there is no wind
assuming the delay is less than about 5 seconds (more and the probable decay in forward speed overwhelms)

then it is simple, just a function of jumpers forward speed on exit and time after exit.

a sprint of 15mph off a vertical wall gets you about 100' after just over 4 seconds

everything changes if anything changes.
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Re: [Calvin19] object seperation
In reply to:
assuming a vertical object, (no overhang on exit, etc,
assuming the jumper is not using aerodynamics to gain distance, (tracking)
assuming there is no wind
assuming the delay is less than about 5 seconds (more and the probable decay in forward speed overwhelms)

All of these things assumed, it seems that it would still be more complicated than figuring the speed at exit calculated over time, which is how I am assuming you came up with the 100' figure.

It seems to me that there should be more of a parabala effect as gravity and wind resistence overcome your foward momentum. Like when you spit off an antenna, it only goes so far on momentum before it starts to either drop straight down or drift with the wind.

The same should apply to a jumper, but how long will your initial momentum carry you forward, and at what rate does your momentum deteriorate? If you gain 20' in the first second, how much will you gain in the second? It shoul be less, but how much less? There has to be a way to roughly calculate this with parabula formulas, but I'm not that good with math. Unsure
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Re: [hikeat] object seperation
My figures show that you will have a much higher separation coefficient if you are either nude or in a thong. If you are concerned with getting the maximum separation in case of an off heading I would highly recommend on of these.Wink
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Re: [sulflik] object seperation
haha, I like wearing my clothes and my protective gear, makes me feel semiquasisafe.
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Re: [hikeat] object seperation
When Chuck Norris BASE jumps, the object moves away from him so he dosent have to track...
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Re: [sulflik] object seperation
Borat Goes BASE JumpingCoolCool
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Re: [hikeat] object seperation
hikeat wrote:
assuming the delay is less than about 5 seconds (more and the probable decay in forward speed overwhelms)

that is why I added this, I did this problem figuring out how to exit a plane slider down years ago.

most importantly, vertical ad horizontal speeds increase and decay, respectively, separately of each other.

meaning, yes, the plot would be a 'parabola'.
in the first second you get 20' separation, and in the second something like 18, then 14, then 6, but drag increases exponentially with respect to speed, but the same can be said with the lack of speed, meaning you go from 100kt forward speed to 50 MUCH faster than you go from 50 to zero.

this, of course, is a completely retarded discussion to be having, there is no way to give a 'correct' answer.

a running exit is better, a strong push is better, a good sub-terminal track entry is better, as long as you can stick the exit and deployment/extraction body position.
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Re: [hikeat] object seperation
In reply to:
It seems to me that there should be more of a parabala effect as gravity and wind resistence overcome your foward momentum.

Not gravity, only wind resistance.
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Re: [hikeat] object seperation
http://fba.base-jump.org/index.php?Tp=articles&Id=28&Type=article&Lang=fr&PHPSESSID=893d373f1b3049865141503800d2e4a5

This article will give you indications about the subject.

Roughly, it says that horizontal speed will vary from 3,5 m/s, to 5 m/s; depending wether you push normally, up to " as if your life was depending on it".

This means a seperation between 50 and 80 feets after 5 seconds of delay, wear track schould overcome the effects of spring.

These measures were made from standing position (without run-up), with impulsion on one foot, and wearing gear.

It also says that a good sprinter can reach 10 to 12 m/s with a few meters to run ...