hard opening

[mrbiceps 0]

So i brought this ripper 95 javelin from the states with only 20 jumps on it. It came with a 215 monarch zero p main with 90 odd jumps on it. This is the first zp canopy i have ridden and man this thing opens hard. I am sure that it opens harder than the 235 falcon f-111 i have been jumping. Is this common for a zero p canopy to open harder than an older f111? I flat pack it and wondered if this was the reason but the guy who did the reserve re pack packed the main and it still nearly snapped me in half when it opened.
Or are monarchs renowned for hard openings?
thanks for your help.
i was doing a bit of freeflying at the time but always arch before dumping. Maybe i need to arch for a bit longer to slow myself down more?

[likestojump 3]

Quote

So i brought this ripper 95 javelin from the states with only 20 jumps on it. It came with a 215 monarch zero p main with 90 odd jumps on it. This is the first zp canopy i have ridden and man this thing opens hard. I am sure that it opens harder than the 235 falcon f-111 i have been jumping. Is this common for a zero p canopy to open harder than an older f111? I flat pack it and wondered if this was the reason but the guy who did the reserve re pack packed the main and it still nearly snapped me in half when it opened.
Or are monarchs renowned for hard openings?
thanks for your help.
i was doing a bit of freeflying at the time but always arch before dumping. Maybe i need to arch for a bit longer to slow myself down more?

monarchs are fairly known for hard openings. Out of the 3 that I have jumped all were cured with putting pockets on the slider.

[mrbiceps 0]

can u explain to me what is involved in putting pockets on the slider? thanks

[koppel 4]

pockets are an extra piece of material sewn along the leading edge (front) of the slider that restricts air getting into the nose of the canopy briefly slowing down the opening.

send me your slider and we will sort it out for you. See you back on skysurfer.com.au

I like my canopy...


...it lets me down.

[likestojump 3]

beat me to it :)

here's a picture

[mrbiceps 0]

Thanks for the help guys. i rang a local rigger up and he suggests trying a bigger slider first and seeing how that goes. if that doesnt work a pocket may be the go.

[fred 0]

Quote

Thanks for the help guys. i rang a local rigger up and he suggests trying a bigger slider first and seeing how that goes. if that doesnt work a pocket may be the go.

Newbie question: If this is a correct statement, then I either understand my gear or the physics involved properly. I would appreciate some of the experts clarifying.

Wouldn't a smaller slider slow the opening more and a large slider make it worse?

Here's my logic:
A slider prevents line spread. If the slider wasn't present, then when the canopy opens, it would "pop" open and pull all the lines taught to the rig. This would happen fast.

So we put a slider on. The slider groups the lines together, and when that canopy tries to pop open, it restricts it. The canopy can only pop open to as big as the slider is. The slider then "slides" (hence its name) down the lines, more gradually allowing the canopy to spread out.

If you use a larger slider, that initial pop would be greater, and the slide down the lines less significant.

Is this not right? Would a larger slider easy the opening? If so, can somebody explain where I'm going wrong in my thought process?

[likestojump 3]

:)

think 3D, not 2D.

slider is in fact a reefing device, the reefing prevents the "pop" (rapid, out of control expansion), as well as reduces chances of lines entangling.

since you are opening up at high vertical speeds, slider coming down encounters a significant resistance as it pushes against air - so the larger the slider area, the more resistance - the slower the openings.

[Piece 0]

While not a very experienced skydiver, I think I can field this one. The bigger the slider, the bigger the drag keeping it up at the lines. This drag produces a lot of the resistance to the canopy spreading. Think about why we uncollapse collapsible sliders. Find some photographs of parachute openings right as the skydiver feels the snatch force (I may edit this post with some links) and notice how "bent" the slider looks. This is the drag that's keeping it up.

Edit: also, bigger sliders cover more of the nose, preventing an in-rush of air that would snap the canopy open. That is one of the reasons why you want to make sure the slider is all the way up the lines when packing.

http://icanhascheezburger.com/2008/02/28/funny-pictures-i-come-with-sarcasm/
Proudly uncool since 1982.

[mnskydiver688 0]

Also another thing to consider is leverage. The smaller the slider the more leverage the outside lines have on the slider. This increases the force pushing the slider down the lines.

Sky Canyon Wingsuiters

[JerryBaumchen 1,446]

Hi fred,

Studies by Gary Peek indicate ( show ) that a slider dimensional increase in the front-rear direction is the major factor in slowing the openings.

Try a SEARCH for 'PEEK' and you might find his work.

JerryBaumchen