Tracking up/down line of flight

[billvon 3,107]

A comment from the recent incident brought this to my attention:

There were a few comments along the lines of "they shouldn't have been tracking up line of flight" even though this incident involved a 4-way.

This is somewhat backwards. The #1 priority at breakoff time is to get clear from the other people on your dive; that's why we break off instead of just pulling in place. Deciding to reduce your separation (by, say, not tracking off from the center of the dive) so as to not "track up the line of flight" is a mistake; the biggest risks are the people closest to you.

For solos and tracking dives it makes sense to avoid going up or down line of flight. For 2-ways, it can make sense to go left and right of line of flight IF (and this is a very important if) you do not sacrifice separation or altitude to do so. A coach and his student might well practice just this, with the student tracking off first in one direction and the coach tracking off in the other. With two less-experienced people it may make more sense to just ensure they are leaving 180 degrees from each other.

For 3 or more, the priority is getting away from the other people on your dive, and ensuring separation from other groups by allowing more time. Having two people track close to each other to "avoid the line of flight" puts you at more risk for collision overall (IMO.)

[Jbag 0]

i prefer to just deploy from the round....decide who has biggest canopy to smallest and have the person to your right pull for you =D

make sure it goes biggest to smallest in a right hand...last guy must have an AAD though.

=D

IHYD

[brettski74 0]

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This is somewhat backwards. The #1 priority at breakoff time is to get clear from the other people on your dive; that's why we break off instead of just pulling in place.

Agreed.

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Deciding to reduce your separation (by, say, not tracking off from the center of the dive) so as to not "track up the line of flight" is a mistake; the biggest risks are the people closest to you.

I think I get what you're saying and if so, I agree, but since it is possible to track too far and meet the neighbouring group at deployment, should it not be said here that you need only track outwards along your radial as far as is necessary to adequately clear your team mates for safe deployment.

[AndyMan 7]

The biggest problem I have with the "don't track up the jumprun" rule is simple. The people at whom the rule is directed (newbies), are simply terrible at being able to determine the direction of jumprun a few moments past exits.

If you take a group of people who can not build a donut without rotating 720 degrees, do we really expect these people to be able to accurately recall the direction of jumprun? After chasing a grip for two full rotations? Call me skeptical.

And of course, once someone gets good enough that they can accurately recall jumprun direction, it's very likely these jumpers are often on jumps where the rule doesn't apply - like larger formation.

It's a silly rule that the people at whom it's targeted can't follow, and the people at whom it isn't targeted don't follow.

"Don't track up the jumprun" is not the solution for deployment collisions between rw groups. Proper exit separation is.


(the rule IS good for tracking groups and wingsuiters, but I don't think that's what you're talking about)

_Am

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You put the fun in "funnel" - craichead.

[davelepka 4]

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The biggest problem I have with the "don't track up the jumprun" rule is simple. The people at whom the rule is directed (newbies),

These would be the last people the rule is directed at. Group seperation is generally such that anything equal to, or less than, a moderate track is acceptable for tracking in any direction from break off to opening, and still allow for seperation between groups.

It's the more experienced jumpers, those that can go from RW to max track almost instantly, reduce their vertical speed to extend their time-in-track, and trypically pull lower than the newbies allowing even more time-in-track, that need to be aware of the jumprun and it's relation to their track.

A good tracker can cover an easy 1000ft horizontal tracking from 4.5k down to 2.5k. A great tracker can do 1000ft from 4k down to 2.5k. If you have one of each on two subsequent groups, you would need in excess of 2000ft between groups to make sure those two jumpers can never 'meet' in the middle, and you just can't do that in one pass and expect all jumpers on the load to make it back to the DZ.

Group seperation is set up to allow for adequate seperation from the other jumpers in your group, and no more. Group seperation is not an open invitation for any jumper to track any way they see fit in any direction.

[AndyMan 7]

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Group seperation is set up to allow for adequate seperation from the other jumpers in your group, and no more. Group seperation is not an open invitation for any jumper to track any way they see fit in any direction.

On anything bigger than a 4way, you are essentially guaranteed to have someone tracking up or down jumprun. The only way to ensure proper separation is exit separation.

_Am

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You put the fun in "funnel" - craichead.

[davelepka 4]

Granted, and that's why bigger formations should be given more time between them and the group following them.

Let's say that an average jumprun for an Otter is 50 seconds. If every group is the same size, you would divide that time up euqally between the groups, and there is your exit seperation.

If a group is larger, and putting more of the load out in one exit, the remainder of jumpers in the plane can dedicate more of the overall jumprun time to that group, and still expect that the rest of the groups will have adequate time for good group seperation and still make it back to the DZ.

I am aware that jumprun isn't a 'timed' affair, but in the end, each jumprun does take a specific amount of time, and division of that time between the groups is what allows you to give an 8-way a little more space, and a solo a little less. While reducing the seperation between solos or two-ways isn't neccesary, increasing the seperation for bigger groups is essentail for making sure that everyone has their own space.

Even in the case of increased seperation due to a larger group, the fact remains that a jumper who is on the jumprun, and aware of it, should moderate their track to the minnimum required for seperation from the jumpers in their own group, and no more. While this minnimum will be more on an 8-way than on a 4-way, it may still be less than a full on track from break off to opening.

Establish the group seperation with average sized groups and average jumpers in mind. Adjustments need to be made to the seperation for bigger groups, and to the magnitude and duraiton of the tracks for good trackers who happen to be going up or down the jumprun.

Skydiving is dynamic environment, and the bigger you want to go, either in group size or tracking ability, the more important it becomes to stay on top of those changes and adjust your plan accordingly.

[billvon 3,107]

>should it not be said here that you need only track outwards along your
>radial as far as is necessary to adequately clear your team mates for safe
>deployment.

That's a fair statement, and I would add that you can control this in large part by deciding breakoff and pull altitudes beforehand. That's not a 100% solution (there will always be 8 ways with one slowpoke and one superstar tracker) but it goes a long way towards getting people far enough away from other people on that dive, but not so far as to risk contact with the next group.

[billvon 3,107]

>If you have one of each on two subsequent groups, you would need in
>excess of 2000ft between groups to make sure those two jumpers can
>never 'meet' in the middle, and you just can't do that in one pass and
>expect all jumpers on the load to make it back to the DZ.

Some solutions for that:

1) Do two passes
2) Reduce breakoff altitudes
3) Increase pull altitudes
4) Rearrange groups so that you don't have those groups next to each other
5) Talk to the exceptional tracker and ask him to not track for 1000 feet.

[davelepka 4]

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5) Talk to the exceptional tracker and ask him to not track for 1000 feet.

If you read the rest of my post, this is exactly what I propose as a solution. The remainder of your list is either impractical, or not reliable in their implementation. My choice, #5 from above, only requires the participation of one jumper, the exceptional tracker, and seeing as how their performance can effect their safety, it's a fair bet they will comply, in full, every jump.

[billvon 3,107]

>The remainder of your list is either impractical, or not reliable in
>their implementation.

OK. At many DZ's they are both practical and reliable, so I guess it depends where you jump.

[davelepka 4]

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>The remainder of your list is either impractical, or not reliable in
>their implementation.

OK. At many DZ's they are both practical and reliable, so I guess it depends where you jump

I'm not sure how the location would have an effect on the practicality of your list.

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1) Do two passes
2) Reduce breakoff altitudes
3) Increase pull altitudes
4) Rearrange groups so that you don't have those groups next to each other

Option 1 is impractical for obvious reasons. It increases both cost and time for the loads. You wouldn't want to do it on every load, just the applicable loads, but then how do you determine which loads are, or are not, applicable? With the myriad of variations between groups, fall rates, wind speed, etc, it just isn't practical.

Options 2 and 3 are not reliable becasue, for one, they rely on the entire group understanding the problem, agreeing to the solution, and all performing correctly on the bottom end. Furthermore, by essentally shortening the time betweeen break off and opening, you are putting the squeeze on those jumpers who do not have a rocket-track, and need more time on the bottom end.

The fourth option is similar to the first option in that it requires someone to indentify the problem situation, and devise a plan to correct. Again, when the call is made, and when not, becomes subject to a judgement call.

The 5th option -

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5) Talk to the exceptional tracker and ask him to not track for 1000 feet

-relies on only one jumper, the exceptional tracker, taking action and only in one specific scenario. If they find themselves tracking along the jumprun in the direction of another group, slow down, go easy, and fly your canopy back the other direction after opening. It's a contained situation that only requires the participation of a single jumper who has a vested interest in avoiding a collision casued by tracking too far along the jumprun.

A jumper with the skill to out-track the group seperation needs to also be aware of the jumprun, and able to recognize when they are tracking along it toward another group.

[billvon 3,107]

>I'm not sure how the location would have an effect on the practicality of your list.

Option 1) (two passes) you claim is impractical. It may be where you jump; out here it is not. I've been on loads that made three passes at altitude. This is usually followed by impassioned pleas from manifest to climb out faster, but this happens on the ground, not on jump run. It's definitely an option here, but I understand there are places where it's a problem (like the former WFFC.)

Options 2) and 3) restrict how much a jumper can track. If you have outstanding trackers who can cover 2000 feet with 2000 feet to track, they will cover less than 1000 feet with 1000 feet to track.

Option 4) (rearranging groups) is similar to option 5) in that you have to identify who the "long trackers" will be - and has the additional problem that you need, say, 3 identically sized groups to have it work out.

>The 5th option (Talk to the exceptional tracker and ask him to not track
>for 1000 feet) relies on only one jumper, the exceptional tracker, taking
>action and only in one specific scenario.

Well, it also requires knowing who they are beforehand; that's not always the case, and all too often only becomes apparent after a few close calls. (The first close call is usually chalked up to "they didn't leave enough time between groups.") But if you can identify such people, yes, it works as well.

[brettski74 0]

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you are putting the squeeze on those jumpers who do not have a rocket-track, and need more time on the bottom end.

The solution to that is don't take jumpers on larger formations than their skills allow. 2/3/4 way jumps don't require huge separation, so a poor track may be enough to get away. As the formation gets larger, you need to get further away and tracking skills become more important. Work on improving their track before they scale up.

[davelepka 4]

You realize that your argument against option 5, that being that you have to indentify 'problem' jumpers before hand to counsel them on tracking, also applies to options 2, 3, and 4. In all cases, you have to know beforehand who to target, and take corrective action beforehand.

That said, option 5 allows you to speak to every jumper, and make it a standard thing to tread lightly if you track up or down jumprun. Once you spread the word, your corrective measures are complete, and the rest is up to the individual jumper who finds themselves tracking along jumprun.

If you go with options 2, 3, or 4, you still need to inform jumpers of the problem, how to handle it, but beyond that, you have to count on large groups of people to act to make that solution work. Entire loads, or individual formations have to alter their plans in order for these solutions to be effective.

The last time I checked, the simplest solution with the fewest 'moving parts' is generally the best bet for actually working in the long run. Option 5 relies on the single jumper to perform, and the other options rely on groups of jumpers performing properly.

Option 1 may be viable for you folks in Perris, where there are multiple fast turbines available, and 12 months out of the year to jump them. In other parts of the country, where we don't have those luxuries, making multiple passes can eat into the overall number of loads flown per day, and in turn, per season. If the problem could be sloved by telling people not to burn it up or down jumprun, that is far preferable over adding additional passes to jumprun.