Canopy Dives on opening

[ctremie 0]

Just started packing my own main canopy, it is a silhouette 230, I PRO pack it as taught, very simular to the PD Nick Grillet's pro pack a large canopy video. but on opening it tends to surge forward, or dive on opening, afer it gets completely open, and only dives for about 3 seconds then levels out. Is this something I am doing wrong in the pack job, I do set the brakes, any help would be appreciated, thanks

[likestojump 3]

I am betting that your deployment brakes are too deep and you are opening in a stall.

[ctremie 0]

Thanks for the insight, How can I check that my deployment brakes or deep or not deep? Also for more info on this, I took a canopy course last week, the dz packers packed it for that day and I didn't have the surge. During the course, to stall my canopy on the toggles, I had to single wrap my brakelines while flaring.

[PiLFy 3]

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Thanks for the insight, How can I check that my deployment brakes or deep or not deep? Also for more info on this, I took a canopy course last week, the dz packers packed it for that day and I didn't have the surge. During the course, to stall my canopy on the toggles, I had to single wrap my brakelines while flaring.

Bring one of those Packers a case of beer on a slow weekday. They know something you don't. Are you quartering your Slider properly? My Sabre2 was doing some diving on opening. I was advised to try quartering as usual. Then, pull the Slider towards the nose a couple inches. It works like a charm .

Get w/a rigger or packer, & get it sorted out.

[djmarvin 2]

Rory can check the trim for you in the loft. Next time you see me at the DZ hit me up and I'll see what I can do to help as well.

DJ Marvin
AFF I/E, Coach/E, USPA/UPT Tandem I/E
http://www.theratingscenter.com

[DJL 235]

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Get w/a rigger or packer, & get it sorted out.

Yeah, same thing.

"I encourage all awesome dangerous behavior." - Jeffro Fincher

[PiLFy 3]

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Get w/a rigger or packer, & get it sorted out.

Yeah, same thing.

I didn't say they were...

[ElectricFetus 0]

total noob question here so go easy on me....

if it surges or dives, but stabilizes quickly, what is the harm?

is it a question of overall stability of the jumper, or is it the potential of loss of control of the canopy?

[PiLFy 3]

Potential Canopy collisions on opening. Other Jumpers sometimes end up way too close when you open. If you're thrown out of control when that happens? Bang... Plus, at higher wingloadings, it could throw you into line twists.

[pchapman 279]

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if it surges or dives, but stabilizes quickly, what is the harm?

Good point. It all depends on what kind of "surge" we are talking about. All canopies pick up forward speed at the end of the opening sequence so how much more is a short duration surge adding? Who cares if a bigger canopy surges when you'd be moving much faster with a sub 100 crossbraced canopy anyway?

If it is the type of surge forward that happens after a stall, then the canopy doesn't have much forward speed to begin with, so it is safe in that way. But since stall behaviour can be more unpredictable and unpleasant the smaller the canopy, you don't want even minor stalling on opening. [Experienced jumpers: Yeah Sigma reserves are interesting...]

While a surge on its own may not be an issue, controlability is. If the forward dive is sudden enough, it may unload the lines a bit and especially if one is bouncing around a little at the end of opening, or not perfectly symmetrical, or the canopy is hunting in direction during the opening, loss of some line tension could allow one's body to twist enough to twist up under the canopy.

So it is all a matter of degree. Every canopy varies in how much distance it takes to open and then picks up forward speed, but if a surge is enough to reduce line tension significantly then it could become a problem.