Freefallers Near Canopy

[RippedCord 0]

Horizontal Separation

AMDG

[jakee 1,257]

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The same thing happens with the other guys. They just got tired of trying to dealing with it, that's why they decided to exit linked.

So it was a 4-way freefly where no-one could even fall straight down the tube?

Maybe exit seperation isn't the only safety issue on those jumps.....

Do you want to have an ideagasm?

[fudd 0]

Second, degrees, discussion....what about common sense? There's no easy solution to the equation....
Winds hav far more to say. If there is no winds at jump run heigth and the plane goes 80 knots, then ground speed is 80 knots. If wind speed is 40 knots and jump run goes upwind, then ground speed is 40 knots, and seperation times will have to doubble.

Remember that if it's windy up there its likely more windy further down. The jumprun can last longer, and those out last will more easyly get back from a long spot.

If I get asked about seperation times I'll go by this:
Between experienced RW/FS groups at least 5 seconds
Between unexperienced RW/FS groups at least 8 seconds
Between RW/FS and experienced freeflyers at least 10 seconds
Between unexperienced freeflyers and anyone at _least_ 12 seconds.

If there is windy I add to those times. Depending on dropspeed those numbers can fine be doubbled. in high wind.

Low time jumpers can easyly drift quite a bit. Low time jumpers are generally less aware of other jumpers. Experienced jumpers will often (not allways!) spot other groups in freefall.

If in doubt add some seconds. If i have the exit count I wait until the seperation seconds have passed...then go ready set go. A 5 second seperation becomes a 7 second one. Much better than a 5 second one becomming a 3-4 second one.

When in doubt....wait...

Also in some situations it's useful to scare the group behing you a bit. "Hey! We're trying something new and probably going to drift like crazy...keep some distance, will ya?"

Also...it helps if the first group out doesn't wait 20 seconds before getting out. Look down, spot, jump.....

There are only 10 types of people in the world. Those who understand binary, and those who don't.

[rehmwa 2]

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if it's windy up there its likely more windy further down

where we are, the uppers are usually higher than the ground winds. I think this is typical most places.

Other than that, I like your thumbrules, as long as we pay attention to the a/c penetration and adjust.....

If we are on a normal unwind jump run and I don't know the wind layers, I have one thing I do always. (this assumes ground and uppers in the same direction and ground typical lower than uppers.......)

When the plane is on jump run, I watch the ground and see how fast our ground speed looks.

If we are crawling along slowly, then I assume the uppers are cooking - so I take/advise long delays between groups - sometimes VERY long delays (this weekend we were taking a slow 20+ count between climbouts from an Otter with a ton of small ways - everyone landed on all weekend - jump run ground speed was less than 35 mph - it was a bit windy up top)

If we are booking along fast, then the uppers are negligible and we can climb out and exit with little delay between groups. Even just a couple seconds can be enough.

With the general lack of understanding of drift, I'm starting to appreciate DZs that do cross wind runs.....

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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

[rehmwa 2]

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Also...it helps if the first group out doesn't wait 20 seconds before getting out. Look down, spot, jump.....

At nats, we were 2nd out. The 1st group was getting out on the green and having issues the first half of the meet. We agreed and encouraged them to spot themselves a bit better. The delay between green light and climbout for them was over 45 seconds. With that, all 4 teams landed on the grass landing area with no issues.

No substitute for understanding spotting for the plane.

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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

[billvon 2,421]

>Second, degrees, discussion....what about common sense? There's
>no easy solution to the equation....

Separation equals (groundspeed of aircraft + winds at opening) * time, which is pretty straightforward.

>If there is no winds at jump run heigth and the plane goes
>80 knots, then ground speed is 80 knots.

Well, if its airspeed indicator says 80 knots it's actually going about 92 knots. I find a better way to figure out what's going on is to just look at the GPS speed display. If it says 65 knots, then the airplane's ground speed is 65 knots. No conversion factors, wind compensation or other figuring required.

>If I get asked about seperation times I'll go by this:

Those are all decent rules of thumb that will cover most situations. I think the key isn't knowing that you must leave exactly 5.6 seconds, it's just knowing that 7 seconds will probably be OK.

[billvon 2,421]

>At nats, we were 2nd out.

We were fourth out and had no problems with the spot at all. I think this was due to our position in the lineup - we were 301, and thus were following Airspeed, Elsinore Gravity etc out, and those aren't teams that take a long time in the door.

OTOH Perris Voltage had three advanced teams in front of them and had a lot of trouble with spots, I think because some of the other advanced teams in front of them were taking forever in the door.

(Which team were you BTW?)

[fudd 0]

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Those are all decent rules of thumb that will cover most situations. I think the key isn't knowing that you must leave exactly 5.6 seconds, it's just knowing that 7 seconds will probably be OK.

There are only 10 types of people in the world. Those who understand binary, and those who don't.

[kallend 1,640]

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Those are all decent rules of thumb that will cover most situations. I think the key isn't knowing that you must leave exactly 5.6 seconds, it's just knowing that 7 seconds will probably be OK.

I suppose someone needs to point out that it took people with a physics/mathematics background to figure out what works, and more to the point, what doesn't. I think you'll find that the "45 degree myth" was debunked by such folks.

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The only sure way to survive a canopy collision is not to have one.

[rehmwa 2]

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>(Which team were you BTW?)

we were Fast FWD in intermediate - we had 8 really good rounds but tanked the all random - ouch that hurts

(I know, we were training AAA all season but just barely clearing a 10 average, but this was more fun for my newer teammates). And first nats for us all. You guys were in the tunnel just before us too.

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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

[billvon 2,421]

>And first nats for us all.

Cool! It was the first Nationals for Molly as well (our point.) Having the bigger tunnel there was a really nice addition to our last-minute training.

[rehmwa 2]

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>And first nats for us all.

Cool! It was the first Nationals for Molly as well (our point.) Having the bigger tunnel there was a really nice addition to our last-minute training.

I had a nice talk with Molly on Monday night at the basketball court.

edit: the only thing new I've really gotten out of all these repeat threads is that Kallend should wash his dog more often

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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

[kallend 1,640]

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>And first nats for us all.

Cool! It was the first Nationals for Molly as well (our point.) Having the bigger tunnel there was a really nice addition to our last-minute training.

I had a nice talk with Molly on Monday night at the basketball court.

edit: the only thing new I've really gotten out of all these repeat threads is that Kallend should wash his dog more often

That would change the timing and hose the last groups out.

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The only sure way to survive a canopy collision is not to have one.