Basejumper.com - archive

Sent my canopy off to apex to get vented and am not sure if i should get 4 or 5 cells vented? What do u guys think? cheers

Question is too vague home skillet. You need to give more info, like what type of objects you're going to be jumping.

Most of the jumps where i live are low. The main jump is 180 feet. Some others are 400 and the biggest i think is around 700 feet. I am planning on going to norway at some stage this year also. thanks for your help.

I am probably wrong, like usual, but my thinking
is your body weight, gear weight, & canopy size
should also be factored into the decision.

Bigger guy, more gear, more weight. bigger wing
all being hucked from low altitudes then get the
5 vents. If not maybe lean the other way.

Is this thinking correct guys?

I'm thinking just sell the canopy and buy an existing vented canopy. I can't imagine retrofitting is wonderfully cost effective, you lose access to the canopy, and instead of guessing on the number of vents, why not demo an existing model?

but that's me...
K.I.S.S.

Four of them, on the 4 right cells.

No, it's not cost effective at all. They would have to rip out too many seams and effectively completely reconstruct the canopy. And then the quality control issue is of concern given that so much custom work is required.

Question should be more like 4 or 7 cells.

Diffrence between 4 or 5 is whether or not the centre cell gets vented.

The centre cell takes almost all the initial load on opening and given that most of your next 100 jumps are gonna be slider-down then you should retain the integrity of the centre cell by leaving it unvented.

If you wanna get into dirty-low ff then get 6 or 7 vented,maybe even look at Apex's new Fox XS. The little advantage 5 cells have over 4 is not worth the loss of integrity to the centre cell to me.

Just my opinion.

g.

Gidday,

As Gp said mate, venting 4 cells is pretty standard. FYI: I got a quote for retrofitting vents from PA and it was a fucking joke...

I have 4 cells vented and would jump it from anything in Oz happily

(Hell, NBdg has been jumped on a retro-vented x300).

good luck

I recently sent my FLiK off to Apex to get vents put in it. I chose to get 4 cells out of the seven vented. In my opinion having any more than four cells vented isn't going to provide any noticeable difference in opening speed at lower altitudes. Before you would be able to notice the difference you would need to be on a static line anyway, and at that point your going to have instant canopy anyway so what's the point? I free fall objects on this canopy from heights of 200' to 2000' and it seems to work pretty well. I would recommend getting the standard four in the interest of utility and pack volume. I like the guys at Apex pretty well and they rushed my service so I could have my canopy back right away. Save the extra money on all the extra cells and get a large pilot chute. Also I liked Jesse Hall's packing video. The pack job taught in there opens immiediately and on heading every time (knock on wood).

Overall I would say the important part is that you have a parachute to begin with, after all its just a damn bed sheet with strings on it.

what's the cost? I asked several years ago for a quote and it was really expensive. I'm surprised it's affordable now.

a 3/7 venting retrofit just cost me $400. a 4/7 retrofit costs $450.

sorry dude, you are not seeing the whole picture.

people keep thinking that venting 5 cells instead of 4 cells increases the vented area. It is absolutely not NECESSARILY so. When Troll went to the DW configuration, they switched from 4 to 5 vented cells (with center), but vented the same square area - each vent was just smaller. As one of the posters above said venting the center cell helps inflation.

Think of how your packjob is presented to the relative wind, and first thing that happens prior to full bottom skin expansion - your center cell bottom skin is presented to the wind.

the picture attached is right as the TG let go, the tailpocket is still slumped, and the canopy is still doing more vertical movement than horizontal (PC is standing up).

I like todd's article.

http://www.apexbase.com/...t.php?education_id=4

For what it is worth, I have 2 vented canopies, one not vented. The not vented is an ultra-lite slider up canopy.

I have the typical vents on my flik and rock dragon and am happy with them, especially on the sub 200' stuff where I have a pressurized canopy in short order.

_justin