EVERYONE should barrel roll.

[davelepka 4]

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you're supposed to be looking for (and avoiding) what is below you, not what is above you ... let the person above you look for (and avoid) you.

Let's re-phrase that. You should be looking where you're going, and while you're tracking, down and out is where you're headed, and where you should spend the majority of your time clearing.

However, when you go to pull, you're new direction of travel (relative to other freefallers) is up. This is why you also need to take a look over each shoulder to clear that airspace before pulling.

Low man has the right of way, blah, blah, blah. If everyone looks out below, than anyone above you will see you a take action, blah, blah, blah. If everyone was perfect, we wouldn't need reserves and we would neve have accidents, but that's not the case. The person above you should look out for you, and should see you, and take some sort of action, but nobody's perfect. Take a look before you radically change your direction of travel (in a relative sense).

[brettski74 0]

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Or it could have been due to what he said in his post:

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Other jumper said they may have flown up jump run at about 2,500 putting them right below me.

I'll say it again, under most conditions, if you have adequate exit separation, it is simply not possible to fly your open canopy underneath the next group before they deploy. The canopy simply doesn't have sufficient forward speed. The exception to this is if you have a large difference between winds at exit altitude and deployment altitude, then it may become possible. Taking a simple example case of no winds, 85 knot jump run, 20mph canopy air speed, 7 seconds between groups, jumpers fall straight down and track 200' from centre at break off. If we have two jumpers in adjacent groups tracking towards each other, they're deployment positions are still 600' apart. In the 7 seconds it takes the second jumper to get to deployment altitude, the first jumper could fly about 200' closer to his deployment position, but that still leaves them 400' apart. The distance can get smaller as you increase the upper winds (or more correctly, the difference between the upper and lower winds), however, the difference has to get pretty significant before you start to get people over top of open canopies - like about 40+ knots difference. That could happen, but I can't recall any time I've seen that and considered the ground conditions as jumpable, so at best, I'm thinking that is rare.

Could avoiding flying up/down jump run immediately after opening mitigate these risks further? Sure it could. Is that something I'd want to rely on? No. Who knows what direction your canopy may be flying in if you're kicking out of line twists or some other correctable canopy issue. If you're finding yourself opening above other canopies, you need to look at the exit and freefall to resolve the problem.

[timmyfitz 0]

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Or it could have been due to what he said in his post:

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Other jumper said they may have flown up jump run at about 2,500 putting them right below me.

I'll say it again, under most conditions, if you have adequate exit separation, it is simply not possible to fly your open canopy underneath the next group before they deploy. The canopy simply doesn't have sufficient forward speed. The exception to this is if you have a large difference between winds at exit altitude and deployment altitude, then it may become possible. Taking a simple example case of no winds, 85 knot jump run, 20mph canopy air speed, 7 seconds between groups, jumpers fall straight down and track 200' from centre at break off. If we have two jumpers in adjacent groups tracking towards each other, they're deployment positions are still 600' apart. In the 7 seconds it takes the second jumper to get to deployment altitude, the first jumper could fly about 200' closer to his deployment position, but that still leaves them 400' apart. The distance can get smaller as you increase the upper winds (or more correctly, the difference between the upper and lower winds), however, the difference has to get pretty significant before you start to get people over top of open canopies - like about 40+ knots difference. That could happen, but I can't recall any time I've seen that and considered the ground conditions as jumpable, so at best, I'm thinking that is rare.

Could avoiding flying up/down jump run immediately after opening mitigate these risks further? Sure it could. Is that something I'd want to rely on? No. Who knows what direction your canopy may be flying in if you're kicking out of line twists or some other correctable canopy issue. If you're finding yourself opening above other canopies, you need to look at the exit and freefall to resolve the problem.

It is possible to fly your canopy under a group that exited after you. If you can't see how it's possible, sorry. Just about everything is possible so never say never. And as you pointed out, there are always exceptions. In a perfect world we would all be perfect. But it is not and we are not.

[brettski74 0]

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It is possible to fly your canopy under a group that exited after you. If you can't see how it's possible, sorry. Just about everything is possible so never say never. And as you pointed out, there are always exceptions. In a perfect world we would all be perfect. But it is not and we are not.

I never said it wasn't possible to fly your canopy under the next group. I said it was unlikely if you started out with adequate separation at exit and everyone involved kept to their own airspace in freefall. Of course it's possible. It happened. The question is what factors may have contributed to that problem and may need to be addressed in avoiding such problems in future. Avoiding flight up or down jump run immediately after deployment will help, but so will avoiding movement up or down jump run in freefall and adequate separation to start with and canopy flight alone is unlikely to be the sole contributor.

[timmyfitz 0]

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It is possible to fly your canopy under a group that exited after you. If you can't see how it's possible, sorry. Just about everything is possible so never say never. And as you pointed out, there are always exceptions. In a perfect world we would all be perfect. But it is not and we are not.

I never said it wasn't possible to fly your canopy under the next group. I said it was unlikely if you started out with adequate separation at exit and everyone involved kept to their own airspace in freefall. Of course it's possible. It happened. The question is what factors may have contributed to that problem and may need to be addressed in avoiding such problems in future. Avoiding flight up or down jump run immediately after deployment will help, but so will avoiding movement up or down jump run in freefall and adequate separation to start with and canopy flight alone is unlikely to be the sole contributor.

Okee dokie.