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flyboy6554

Hard opening after tracking jump

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I whacked myself pretty hard today after a solo tracking jump.....thought I had given myself plenty of time to slow down and even de arch a bit to further slow, but had an almost instant canopy at pull...not a rushed pack job and no indications of line dump or anything wrong with the canopy, pretty sure it was high speed at deployment.....so my question is: how long does it take to fully slow down after a full on high performance track??

Thanks in advance for all comments.......

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If you go to the Boxman position and sort of flare, throwing your arms up as if to stop the crowd, about 4 or 5 seconds. If you listen carefully to the wind, you can get some clues.

Some often post on these threads that the change in opening is a result of something else and that many deploy in a full track with no ill results. However, I have been in a HP track that had peaked at 140 MPH down and about 100 horz after subtracting the tail wind. That will give a 3D speed that is way in excess of what a sensible person would want to deploy. So yes slowing down is a really good thing.
Instructor quote, “What's weird is that you're older than my dad!”

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dthames

If you go to the Boxman position and sort of flare, throwing your arms up as if to stop the crowd, about 4 or 5 seconds. If you listen carefully to the wind, you can get some clues.

Some often post on these threads that the change in opening is a result of something else and that many deploy in a full track with no ill results. However, I have been in a HP track that had peaked at 140 MPH down and about 100 horz after subtracting the tail wind. That will give a 3D speed that is way in excess of what a sensible person would want to deploy. So yes slowing down is a really good thing.



First of all is nice to know speed and velocity and the relationship between them ;). The magnitude of the velocity of your example is about 172 mph,~149 kts.
150 mph is a quite usual number on the labels of canopies as Maximum Deployment Speed.

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not a rushed pack job and no indications of line dump or anything wrong with the canopy



Line dump does not cause hard openings. If it did, the semi-snowless bags out there would give a hard opening every deployment. They don't.

Not keeping the slider against the stops during "S" folding and putting the canopy into the deployment bags are the #1 cause of hard openings. #2 is not slowing down before pulling.

Derek V

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Thanks for the info. A friend had a really hard opening last night that just about knocked him out. He collapsed when he landed and was really beat up. He'll be okay.

Thing is that he's a really experienced packer both tandem and sport. He has thousands of pack jobs over three or four years and supposedly no cut always. He's also an experienced jumper.

Anyway, he was working with a rigger trying to figure out why he was having somewhat hard openings earlier in the day. They hadn't changed anything yet. He has a Sabre 1 150 in an older Vector.

Can you think of other reasons for a hard opening even if they're theoretical?
Chance favors the prepared mind.

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He has a Sabre 1 150 in an older Vector.

Can you think of other reasons for a hard opening even if they're theoretical?



Sabre1's are known for brisk openings. They are lined with Spectra lines which will shrink with heat. This heat come from the slider grommets as the slider descends during deployment. The outer A, D & Control lines shrink the quickest. This changes the line trim of the canopy, and can result in hard openings.

Derek V

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wicodefly

Thanks for the info, makes sense and I'll pass it on with a grain of salt.

Is the Sabre2 also known for "brisk" openings? I am looking to get a new canopy soon and am considering a new Sabre2.



Nowhere near as much as the original Sabre (sometimes incorrectly called a "Sabre1").

The Sabre2 is known for random turns of up to 180 in either direction on opening, and can open hard on occasion. I was given the suggestion to make sure the slider is pulled out to the sides more than front/back. Of course, make sure it's tight against the stops. That, more than anything else, has improved my openings.

And never, ever forget that any canopy can hit you very, very hard. Sometimes "shit just happens." Throwing a hundred or so square feet of nylon into a 120+ mph airflow is a very chaotic process.
"There are NO situations which do not call for a French Maid outfit." Lucky McSwervy

"~ya don't GET old by being weak & stupid!" - Airtwardo

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Hooknswoop


Line dump does not cause hard openings. If it did, the semi-snowless bags out there would give a hard opening every deployment. They don't.



But is the deployment of a semi-stowless bag actually 'line dump'?
My understand of line dump is that it's when the canopy starts inflating BEFORE line stretch - this can't happen when the canopy is in a bag closed with line stows.

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wicodefly


Can you think of other reasons for a hard opening even if they're theoretical?



I read a theory on here quite a while ago, where it was suggested that hard openings can be caused by the risers lifting asymmetrically out of the container - this could cause the slider to come down at an angle rather than flat, meaning it has heaps less air resistance and zips down very quickly.

Something else I have noticed on other videos of hard openings is that the tail seems to spread out very quickly, it's like the end cells are inflating before the centre ones.
I believe the biggest contribution to downward force on the slider comes from the brake lines - and if something about the pack job is leading to the tail expanding spanwise very suddenly then I think that force would cause the slider to come down super quick.

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wolfriverjoe


The Sabre2 ... I was given the suggestion to make sure the slider is pulled out to the sides more than front/back. Of course, make sure it's tight against the stops. That, more than anything else, has improved my openings.



That's interesting - I actually improved the openings on my Sabre2 by pulling the slider out at the back as much as I could.

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flyboy6554

I do psycho pack religiously!!



Why would psycho packing help? I'm still learning and am interested in opinions.

My thinking has been that I follow the manufacturer's instructions for packing my specific gear. As you know a rig has multiple manufacturers and some are okay with alternative methods.
Chance favors the prepared mind.

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wicodefly

***I do psycho pack religiously!!



Why would psycho packing help? I'm still learning and am interested in opinions.

My thinking has been that I follow the manufacturer's instructions for packing my specific gear. As you know a rig has multiple manufacturers and some are okay with alternative methods.

You can roll the nose more or less and it will speed up or retard your openings.

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