Why RW exit first ???

[Vlad 0]

this is something i never understood. So many times it has happenned to me: I exited last to freefly, and have beaten rw jumpers to the opening height. This is really unsafe. A couple more reasons for freefly jumpers to exit first: when a big RW formation breaks away, there will be tracking jumpers everywhere, including under everyone who has jumped after them. A big formation looks like a frezbee. It can slide. A freeflyer is usually falling straight down. What do you think ?

[mr2mk1g 10]

http://www.omniskore.com/freefall_drift2.html

[DougH 270]

Because free flyers drift less, so RW groups can actually slide over top of the free fly group. If you put the belly fliers out first drift helps the separation, and less delay is needed in the door to get safe separation. It doesn't matter if you fall faster. Consider what could happen if you had a premature deployment, and the later leaving belly group drifted over top of you. Putting free-flyers out first increases this risk.

Why is it unsafe that you have beaten them to pull altitude? If you have proper separation you will be in a different spot in the sky. You can't rely on vertical separation.

After I am open I try to judge where I stand in the canopy stack, and either bleed altitude, hold brakes, or just fly full flight to my staging area.

"The restraining order says you're only allowed to touch me in freefall"
=P

[billvon 3,030]

> So many times it has happenned to me: I exited last to freefly,
>and have beaten rw jumpers to the opening height. This is really unsafe.

Why? Horizontal separation is what keeps you safe, not vertical separation.

>A couple more reasons for freefly jumpers to exit first: when a big RW
>formation breaks away, there will be tracking jumpers everywhere,
>including under everyone who has jumped after them.

Big freefly - same thing.

>A big formation looks like a frezbee. It can slide. A freeflyer is usually
>falling straight down. What do you think ?

In my experience, freeflyers slide a lot more than RW. A 4-way team barely moves; a 4-way head down slides quite a bit.

[Vlad 0]

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Because free flyers drift less, so RW groups can actually slide over top of the free fly group.

The also can slide under the free flyers, especially while tracking. The chances of that are much higher than of a premature deployment. The horizontal separation does not help. Evern if I give the RW group 12 seconds, they can easily slide under me.

[Vlad 0]

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Because free flyers drift less, so RW groups can actually slide over top of the free fly group.

vs.

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In my experience, freeflyers slide a lot more than RW. A 4-way team barely moves; a 4-way head down slides quite a bit.

Let's decide on whether the freeflyers drift more or less...

[billvon 3,030]

>The also can slide under the free flyers, especially while tracking.

Freeflyers track too!

>The horizontal separation does not help. Evern if I give the RW
>group 12 seconds, they can easily slide under me.

Well -

1) 12 seconds is often not enough. Depends on winds, aircraft speed etc. If you are still seeing problems, wait longer.

2) If you are giving them enough time, and you're still finding yourself near them, either you are sliding or they are. Most small RW groups do not slide much because the people are facing each other and are intent on not moving much relative to the other; the tendency to backslide is cancelled out.

Let's put it this way. If you're getting that close with RW out first, you will be even closer with FF out first. Putting RW out first gives you more separation inherently than putting FF out first.

[pilotdave 0]

I think there's confusion between "drift" and "sliding." They aren't the same thing... Slower fallers have more drift (with the airmass), and whoever moves around more in relation to the airmass is sliding more.

Billvon is saying that freeflyers slide more and belly flyers drift more.

I'm not sure it makes a difference who slides more... encroaching on someone elses airspace is bad no matter who it is. But the whole idea behind putting RW groups out first (on an upwind jumprun) is that they are exposed to the wind longer, and therefore drift farther (away from the faster falling groups). It is unlikely (assuming an upwind jumprun) for an RW group to drift under (or over) a freefly group. They drift the other way.

This is really important to understand... nobody should go suggesting that we change the exit order without understanding why it is the way it is.

Dave

[DougH 270]

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I think there's confusion between "drift" and "sliding."

Poor word choice on my behalf, I intended to write that the rw group can drift over not slide. After all I freefall on a rail, no sliding at all.

"The restraining order says you're only allowed to touch me in freefall"
=P

[jeremy_o 0]

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Evern if I give the RW group 12 seconds

Not trying to target you, but...umm, wait longer? I've waited for 20 seconds going second out on a 2way RW dive after a 2way RW dive. I guess it is a different situation, just be safe!

I didn't understand the exit order at first either, my thinking was that freefliers would be going faster than belly fliers and then during deployment we would be right next to eachother. Now I understand that with a proper exit seperation (and the RW 1st) there is never an issue at my DZ..

I guess I can understand both schools of thought and see the reason for the debate but I'll go with what my more expierenced elders have suggested

http://planetskydive.net/ - An online aggregation of skydiver's blogs.

[Scoop 0]

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http://www.omniskore.com/freefall_drift2.html

Can I just say, that graphic is awesome. For someone like me who really needs to see things visually to understand that is fantastic. I completely get it now. I've often wondered the same. So, faster fallers (ie FF) get out last as this enables greatest horizontal seperation.

Its like someones just turned on a light bulb in my head

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[Scrumpot 1]

"Beating RW fliers to the opening point" in of itself should be of absolutely no concern whatsoever, so long has you have adequate HORIZONTAL separation! Why do you think this is unsafe?

In fact, unless your jumprun is routinely "downwind" (as opposed to into the relative uppers) your getting "down"quicker, and straighter (with less "drift"), so long as you have aleady given adequate exit separation in the first place - will give you even GREATER horizontal separation as a result.

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this is something i never understood.

Clearly, you need to. ...Asking these types of questions though, then considering it further is a great start!

Blue Skies,
-Grant

coitus non circum - Moab Stone

[Vlad 0]

Just as I told before - jumpers in big groups (both freefly and RW) track. THe bigger is the group, the longer they track. They can track from 6000 to 3000. They track in ALL directions, including such which will bring one of them under a solo freeflyist. THe corrected question would be : why does a big way (RW or FF) goes before a solo freefly ???

[labrys 0]

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Just as I told before - jumpers in big groups (both freefly and RW) track. THe bigger is the group, the longer they track. They can track from 6000 to 3000. They track in ALL directions, including such which will bring one of them under a solo freeflyist. THe corrected question would be : why does a big way (RW or FF) goes before a solo freefly ???

Wouldn't an RW group that big be pretty much taking up an entire load? And if not wouldn't the 1 or 2 remaining solo freefliers have more than enough time to give them plenty of time out the door?

Owned by Remi #?

[Remster 30]

A large group will track, regardless if its before or after a solo. Having large groups (that drift more) go before solos (who drift less) in a into the wind jumprun helps with seperation.

Remster

[billvon 3,030]

>THe corrected question would be : why does a big way (RW or FF)
>goes before a solo freefly ???

Big-way RW usually goes first because they drift more (not slide, drift) and thus give you more separation automatically.

Let's say you have a load of all-RW people. First out is a 16-way, then a 4-way belly. The winds are such that the 4-way needs to give them 20 seconds. Fine; those are the only two groups on the plane, so no one's going to land off.

Let's say you have an RW bigway out first, then a 4-way head down. Now the drift helps you with separation. You can leave 15 seconds and still have enough separation. Put another way, if you wait the same 20 seconds, you get even more separation, and are even safer.

Now let's say you have a head-down bigway out first, then a 4-way belly. Now you have to wait 25 seconds for safe separation. Put another way, if you wait the same 20 seconds as the first example, you will be dangerously close.

That's why FF out first = bad in almost all scenarios. It reduces your separation.

[pilotdave 0]

When planning the time between groups, you need to take into account tracking. Bigger groups do tend to track farther, so you need to give them more time. The time we wait between groups of any size should take into account someone tracking straight toward you while you track straight toward him. You need to be far enough apart when you exit that you're still far enough apart when you open, after everybody tracks.

If freeflyers go first, you increase the odds of the belly flyers drifting over the top of them. Bad in case of a premature and bad because groups will be closer at opening altitude.

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why does a big way (RW or FF) goes before a solo freefly ???

Because the big way will tend to fall slower, and therefore drift farther. And they tend to take more time to set up in the door, so going first gives them time to set up before reaching the exit point (assuming they go first).

Dave

[hommie 0]

pm sent

[Scrumpot 1]

Look at the responses you've gotten here. I do not want to seem redundant. You've already gotten several very good responses from varying persons, several of whom explain things here in these forums and in writing much clearer than I. Look at each, and see if you can consider and picture / think each more thoroughly through. It is clear you ARE THINKING, and that is good! I commend you for your thoughts and your questions.

Now take each as well to your DZ. Ask your DZO/DZM and your pilot. Are these skilled, able and experienced people who you trust? Ask them why, and for their particulars of why they operate and use the procedures they do. Ask openly, so as to LEARN, not to be challenging. LISTEN, consider, - take ALL into account and see if you can then come to more of your own thoughts or even conclusions. Do not "rush" the result to have to be right - right away in here either. We'll still be here to debate with you in say a few days, or a week, or whatever it takes for you to simply consider, and discern a little more.

Heck, it's easily taken me SEVERAL weeks in here when I've gotten truly embroiled in a real debate to change my mind (I was gonna say for people to realize I was right - but that might not be entirely PC - or CORRECT! ).

Looks like there've been several good "answers" (or at least responses - depending on how you would like to take them) posted already here for you. What do you think?

Hope they've been of some help.

Blue Skies,
-Grant

coitus non circum - Moab Stone

[Vlad 0]

Thanks, everyone for your replys. It'll probably take me some time to convince myself. Still there are DZs, where it is the other way around. Sure, they have some point as well.

[skr 1]

> It'll probably take me some time to convince myself.

Oh, that's OK, it took me years of thinking about this
and listening to people arguing in various directions
before I got it.

This has been a huge debate since at least the early
1990s.

I think the root difficulty is that our intuitions about
how things work developed for life down here on the
ground where things are close together and not moving
very fast.

If I'm standing on a two foot rock with someone and
we hop off 5 seconds apart I know what's going to happen.

If the rock is 2 1/2 miles high and moving at 90 knots
and we're spending 60 seconds getting blown around
by upper winds then my (unexpanded) intuition about
how things work is going to give me the wrong answer.

So the right thing to do is make the effort to expand
your intuition about how things work, and that starts
by asking the question you asked.

That animation at omniskore is a good start.

John Kallend's program is really helpful.

Lots of people here have tried to understand and explain
this complicated situation.

I put some of Bryan Burke's work and some of Billvon's
early efforts here
http://indra.net/~bdaniels/ftw/index.html
down towards the bottom of the page.

My last effort - Dealing with Uppers - is here
http://indra.net/~bdaniels/ftw/sg_skr_dealing_1_uppers.html


And one more point, besides the freefall drift and forward
throw mentioned by a couple people above, there is one
more factor.

If the fast fallers go first, they are on the leading edge
of the wind cone, which means that they have to face
the target and fly up jumprun most of the way back or
they will land out.

Flying up jump run puts you right in the kill zone when
the slow fallers start arriving 30 or 40 seconds later.


So I think asking questions and wondering why things
are done the way they are is a good idea.

Skr

[idrankwhat 0]

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Thanks, everyone for your replys. It'll probably take me some time to convince myself. Still there are DZs, where it is the other way around. Sure, they have some point as well.

Another way to think about your exit separation is not to think in time, but think distance. A quick rule of thumb would be to allow about 1000 feet of horizontal distance between groups. More if the group in front is a big way. On your next jump check your spot and spend some time in the door watching your ground track. I'm not sure where you're jumping but at this time of year in our corner of the US we get some honking winds at altitude. 30 seconds isn't uncommon.

[rehmwa 2]

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Just as I told before - jumpers in big groups (both freefly and RW) track. THe bigger is the group, the longer they track. They can track from 6000 to 3000. They track in ALL directions, including such which will bring one of them under a solo freeflyist. THe corrected question would be : why does a big way (RW or FF) goes before a solo freefly ???

Here's why

the FFer exits after the big way: (with inadequate exit time) - 6 of the big way track under the FFer - despite the additional drift they get in the upper winds

the FFer exits before the big way: the ENTIRE bigway (all 60) drift directly over the FFer - because of the extra drift they get in the upper winds

...
Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants