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ok... so Ive searched and read about vents and I understand the concept and why to have them, but how many? Im looking at getting another rig, and dont plan on any ultra low jumps, and also want to be able to take the rig terminal and slider off. I know people jump with as many as 5 vents slider up with a mesh slider or altered sail slider, and I understand the more vents you have the faster the pressurization should be on the top skin...

Ive put a few jumps on a Mahem 260 with one vent and it seems to get flying just a little faster than my unvented Dagger 266. I really like the flare on the mayhem and was able to do a 1/2 to 3/4 braked approach and still finish it off with a stand up landing in low wind and no wind...

How much difference is there between 1 and 2 or 3 or 4 vents? I know this is also dependent on the canopy, the size, the wingload and possible wind conditions and possible other factors. I know its impossible to break it down exactly to how many feet of pressurization or time, but just wanting some input from people who have jumped canopies with different vent configurations.

I like 4, 3 is fine too. I wouldn't want to play around real low with 1 vent, and wouldn't want to take 5 or more vents terminal. 3 or 4 vents seems to be a good middle gorund. (even though either would probably work fine for most people). Just my opinion anyway.

a lot of times it's not the amount of vents - it's the total area that's vented.

when Troll went to the DW configuration their stock canopies went from 4 to 5 vents (all but the center cell) - but the total area covered by vents did not change - they just made each vent a little smaller. TrollDW's are taken to terminal every day.

4 vents is what I have begun calling the legacy configuration - it's what all the stock vented canopies used.

My personal opinion is that center cell vent helps cleaner and faster inflation, and as such is a good thing :) - And in contrast with 3 vents - if you are wanting 3 vents, might as well go for 5 :)

I have jumped a few different canopies whether they are vented or not, but not near enough to comment on canopy type.

Although, my Troll 265MDV (5 vents), I've free falled it from 280' to 1800' with no problem or any "too" hard opening. Terminal openings are brisk, but not anywhere near a slammer in my experience.

On terminal as well as 5-7 sec slider up delays, my heading performance has been great with vents.

I only have about 70 jumps on my canopy, so take it as you will. Maybe someone with more slider up & down jumps on vented canopies can comment further.

So whats the difference between 4 and 5? I mean I get the center cell wouldnt have a vent on 4 and it would on 5, but wouldnt the cross ports basically inflate the center cell virtually as fast with 4 as with 5? does anyone notice more heading issues with 4 rather than 5? that would be a semi logical explanation to me. I would imagine it would be easier to get asymetrical inflation with the vents further toward the wing tips than toward the center... I think I am opting for 1 or 3 at this point to get the center pressurized more quickly and still have enough to hopefully keep the canopy inflated with the nose closed off on a cliff strike... so 3 sounds like a magic number. of course the more vents, the more it would stay inflated with the nose closed off (at least by just thinking more openings on the bottom skin would help vs less openings... more thoughts?

Just to correct that but in the DW Troll the center cell is vented as well. It has 5 vents having the outermost cells of the canopy not vented. See for example this picture https://fbcdn-sphotos-a.akamaihd.net/...3758_672731467_n.jpg of my girlfriends brand new DW where you can clearly see the venting on all but outermost cells.

Edited to add : To the original poster regarding the number of vents, I do not know if you can even choose the Troll with specific number of vents, as far as I know it comes standard as vented (5 vents as described above) but you can order it custom non vented too. Personally I do not see why to order it unvented though, I jump my DW Trolls regularly up to terminal speeds both tracking and wingsuits and they open absolutely fine. Actually I would like a bit briskier openings to be honest, my Trolls yield sometimes even a bit too slow and snivelly openings to my taste. But the bottom line is that if you choose to go with Troll there is (from my point of view) absolutely no downside with the vents so I would not even consider getting a non vented one.

All my canopys where unvented with multi untill my last FOX. I ordered it with only one vent on the middle cell (and multi of course, multi rules !).
Nerver tried slider down, but really really good for tracking and/ wingsuit jumps. Very consistent openings, works like a swiss clock

My next one gonna be a FOX Lite with multi + 1 vent ... love it

I havent thought much about the Troll... I jumped a Troll last weekend (unvented) but havent had the cahnce to jump one vented yet... I have mainly been thinking about the Mayhem. I have one as a demo and you can choose 1-5 vents... hence the post about how many :)


I may go with a Black Jack too.... just not 100% sure yet, but my next canopy will definitely have vents... I want one with and one without

just curious why you would want one without vents as well. any technical reasons?

I jump a Blackjack 240 with 4/7 vents and it is perfectly fine at terminal and has great pressurization on the Low stuff. i frequently freefall a 240ft A and open with plenty of time to turn it around for a nice landing into the wind.

Why one with and without? well mainly because I have one without...lol If my rig right now was vented I wouldnt opt for an unvented canopy, but with that in mind I have seen first hand how quickly the seven opens and pressurizes on many occasions (one of my buddys jumps one)... I know the dagger is not a sought after canopy, but I like it so far... I cant complain (but dont have a huge sample of jumps on it)... I like how its a bit "swoopy" on landing, and my brakes are set well, so when I open Im not moving too fast (in my opinion)...

i just sold my OSP and bought a blackjack.

how many vents come on a BJ standard?

i wonder if it would be possible to talk to stane and see about modifying a BJ to get the actual valves installed like on a troll dw MDV/OSP.............

not that its a big deal but i always liked the security of having valves on my OSP in the event of a cliff strike

BJ is 4/7 vents
CR calls them PAC Valves, thus you really need not worry about sending the canopy to Slovenia

Please explain your cliff strike - valve relationship

i was always under the impression that if all of your nose cells hit a solid object straight on, valves close if air is trying to be pushed out of them through the vents, helping to keep the canopy inflated.

am i wrong?

The blackjack does have one way valves. The only canopies ever manufactured standard with two way vents were early FOX vtec's. All the canopies presently on the market with bottom skin inlets have one way valves of one sort or another.

I contacted Atair about putting their MDV valve design onto an Ace several years ago and was told that they were unwilling to retrofit a canopy from another manufacturer.

I believe you are correct in your assessment of the post-strike mechanics.

In my opinion, the valves on any modern canopy will behave in the manner you described.

good news then. i wish i had have put some jumps on a BJ but all i hear from the masses is that they are great all around canopies. plus the deal i got on this rig would make anyone choke on their corn flakes.

So in summation so far, you're thinking about buying a Mayhem from bad seed, and wondered about peoples opinions about the venting option on the Mayhem... (the canopy is important info an not specified in the OP)

The one Mayhem i jumped had 4 of seven vents i believe, and it worked fine on a triple gainer slider up. A good friend of mine jumped a demo Mayhem slider off in bad winds and wound up bouncing off a freestanding A. he said that the venting works and he liked the canopy, but i'm not sure about the number of vents (Brandon would probably know if you ask about it)

My Flik is 4 of 7 vents and was my all around canopy for the majority of my jumping so far including slider up terminal tracking (and large mesh slider. finding the perfect balance of reefing or rolling of canopy material was key to dialing in opening comfort and performance, but that goes for any canopy), i think 3 or 4 vents would be fine on Fliks (there may be debate on the affect of the center cell being vented/unvented and your own beliefs on that would probably be a fine configuration for your next canopy) Another Cincy guy has 3 of 7 and he likes that configuration the most now...

My new Troll 245 has 5 of 7 and i like it very much so far, the flik was starting to loose its flare...

I'm not a fan of the Ace below 270ft, and my Feather 240 works just fine without vents for all my slider up needs.

Maybe someone that has more Mayhem experience can chime in with more about that airfoil's venting situation...

oh, and fill out ur profile, i smell an FJC grad that hasn't found a mentor or crew yet, but i've been wrong before...

it's considered bad practice in the base environment to repeat past mistakes that you can learn from your peers or the BFL... you just won't have as long of a life trying to learn through trial and error all on your own...

ahh... that thing... I am new to the sport. I have over 2k skydives but 17 base (5 objects).... Ill fill it out...

and I do have a crew....

The question wasnt only about the Mayhem... that is the canopy that I am interested in buying and liked how it performed (with one vent). But there arent many people jumping the Mayhem yet, and there isnt much out the in the way of reviews either. I understand many manufacturers have a standard amount of vents you can get on a canopy... the Mayhem, however you can pick from 1-5.... hence the original question...

I opted for 3 vents. I just ordered a complete badseed rig... menace/mayhem with 260, 3 vents (1, 4 and 5 cell) and ZP foreskin... I have a trip to the perrine in april (and Brandon hopes to have it complete before then)... looking forward to more jumps on it and eventually being able to throw in my 2 cents on how it flies/opens.

Cool man! Report back. Brandon is a good dude, I really like his rigs. Would like to hear more about the canopy once you get some jumps on it.

You typed: 3 vents (1, 4 and 5 cell)

I have not jumped a Menace yet and
I like Brandon and Bad Seed BASE...
but venting cells: 1, 4, 5 on a 7 cell
sounds like an asymmetric disaster.

1 2 3 4 5 6 7

If bold represents vents then they
are not symmetrical, maybe a typo?

or maybe he is using PD-like nomenclature, starting from the center out :)

6-4-2-1-3-5-7

re : http://www.performancedesigns.com/...ims/PR_160-281LT.pdf

no... the cells are numberd:

6421357

Okay, cool, thanks, makes sense now.

Not necessarily. Asymmetric is also good. From Wikipedia:



"By changing its sweep angle in this way, drag can be reduced at high speed (with the wing swept) without sacrificing low speed performance (with the wing perpendicular)."

So maybe this is the future of high-performance canopies and wingsuits? Imagine people flying wingsuits with one arm stretched forward and the other arm swept back? It'll look just like Superman coming for the rescue!

I must say... your attention to detail in a post: "symmetricmachine wrote:" made me chuckle...

only a 7 week turn around from order to doorstep... time to break it in at the Perrine this weekend...

this is why I always fly on my left frontriser and right rear riser. high speed performance! B)

I was able to get 9-10 jumps on the Mayhem this weekend and my first thoughts are this:

It flies pretty fast in full flight (forward speed/penetration) with similar wing loading compared to the black jack. It is about the same as my dagger in forward speed.

The three vents I opted for seems like a good pick. when doing packed and unpacked jumps the pressurization was very fast and I was flying as fast as I could reach toggles (Dagger takes quite a bit longer to pressurize and get flying).

The factory brake settings were ok for the bridge, but I will be taking the DBS in about an inch before my next jump.

The brake line length was ok, but I also plan to take that in an inch or two.

Landings were all pretty good... there was quite a bit of wind most of the jumps, and it held up well in fairly turbulant air.

I was able to do half braked approaches and have soft landings and on a no wind jump was able to swoop about 30-40 feet with just a brake/surge approach.

I definitely am a fan and like my new rig... of course its my first new rig so Im sure id like it if it were just about anything.

Any questions, feel free to ask!

Oh, I had the idea totally wrong.

I though when you had a cliff strike and was falling vertically down air went in through the valves and thus kept the canopy inflated.

Nobody said otherwise. Are you learning BASE entirely through this forum?

I was referring to that!!

To your question: No, but I am learning a hell of a lot

Is this some sort of alter-ego? I'm confused.