7 cell canopies

[JohanW 0]

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Does anyone jump a 7 cell canopy? Was wondering the differences between a 7 cell and a 9 cell. I do not see many 7 cells.Thanks Blues.

I do.

Generally, 7-cell canopies have a lower aspect ratio, higher cells, less lift/drag. They tend to be trimmed steeper, though obviously there are exceptions.

9-Cells tend to have a bit more surf on landing, so the flare timing is less critical as long as you keep it flying. This is why 7-cells are said to have less flare. 7-Cells are more stable in turbulence and are less prone to off heading openings. Obviously, these are again generalisations. But there is a reason why almost all reserves, almost all accuracy canopies and (almost?) all CReW canopies are 7-cells.

11-Cells would have certain advantages over 9-cells but tend to have opening characteristics that get a little bit too interesting.

OK, back to the regularly scheduled flamefest now ..

Johan.
I am. I think.

[DSE 5]

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This is why 7-cells are said to have less flare

Generally, they may have less flare...but the Storm has massive flare. Several guys commented on this at Ramblers this weekend when I got caught in a bad spot.

I bad-mouthed 7 cell canopies based on two experiences with my reserve. Then I demo'd the Storm...It's not a reserve with a different trim/lineset. It's an aggressive canopy by most comparisons.

[JohnRich 4]

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I bad-mouthed 7 cell canopies based on two experiences with my reserve.

That's kind of a broad brush stroke you took, based upon only two experiences with one canopy, don't you think?

[JohnRich 4]

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Generally, 7-cell canopies have a lower aspect ratio, higher cells, less lift/drag. They tend to be trimmed steeper, though obviously there are exceptions.

9-Cells tend to have a bit more surf on landing, so the flare timing is less critical as long as you keep it flying. This is why 7-cells are said to have less flare. 7-Cells are more stable in turbulence and are less prone to off heading openings. Obviously, these are again generalisations. But there is a reason why almost all reserves, almost all accuracy canopies and (almost?) all CReW canopies are 7-cells.

11-Cells would have certain advantages over 9-cells but tend to have opening characteristics that get a little bit too interesting.

Now that's the kind of info that Lenzo was looking for, and needs. Thanks for providing that. It's a shame it took this long for someone to get around to it.

What about malfunction characteristics? Are 9-cells more prone to radical malfunctions than 7-cells?

[airtwardo 7]

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Lighten up lad

No, he always posts crap like that. Just because hes an old dinosaur who can't hold a candle to skydivers these days he tries to belittle people with what he thinks is his "ace" card just because he jumped in DaVinci's time.

For a change somebody ELSE is the 'Old Fart'!



Other than that Andy, I dunno if I'd agree with your opinion...

John jumps for a main, a big 7 cell and a spring loaded pilot chute...you know like reserves!

He jumps a lot, is current, proficient, safe and I don't hear about alotta cutaways or injuries from him...that's actually the kind of 'candle holder' some of the 'skydivers today' might need around.
Ya know...you may not agree with the conservative mindset a lot of us old farts have, but you gotta admit if a guy can jump regularly for 30 years and not have a limp, he just may be on to something!

~ If you choke a Smurf, what color does it turn? ~

[shropshire 0]

Great post

(.)Y(.)
Chivalry is not dead; it only sleeps for want of work to do. - Jerome K Jerome

[JohanW 0]

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What about malfunction characteristics? Are 9-cells more prone to radical malfunctions than 7-cells?

If you are talking about spinning linetwists, a Diablo can malfunction just as violently as a Stiletto. (Both are highly elliptical on the trailing edge, but the Diablo has a straight leading edge. The Stiletto does not.)

The number of cells may have an impact. 11-cells are uncommon because the openings are squirrelly, 5-cells are uncommon I think because they just don't have as much lift/drag. Thus, one would expect 7-cells to open more reliably than 9-cells (while having less lift/drag). But other design features, like line lengths, aspect ratio and planform (square vs. elliptical), definitely have an impact too.

I have no idea what influence the number of cells has on the lineover rate. Tension knots, well, less lines ..

My gut tells me 7-cells are more reliable, but I really don't know how much of that is plain the number of cells and how much of that is other design characteristics, and how much those design char's depend on the number of cells more or less directly.

(Yes, I need to demo a Storm. It may be the best of both worlds; it was certainly designed as such and is definitely marketed as such.)

Johan.
I am. I think.

[likestojump 3]

ok, as this topic has been discussed many times (7 cells vs 9 cells), it's silly for yet another thread to appear.

Nevertheless, to be constructive..

This weekend I realized that I actually have about equal amount of jumps between 7 cells and 9 cells :)

7 cells by far have less flare power. No doubt about it (I have no tried the new PD canopies that everybody raves about, so don't know how those compare). Now, just because they have less flare does not mean that they dont have enough - just don't expect your 7cell to fly/flare like a 9 cell and you'll be fine. Same goes for the reserves, where I really believe that the "problem" people are having is not the canopy being a 7 cell, but the canopy being made from F111, thus needing a different flare.

But both are quite nice to fly once you are used to them. Traditionally 7 cells are more forgiving, and that's why many WS pilots prefer them. (short of the Diablo :)

This year so far I have jumped :

Spectre 120 dacron lines
Spectre 135 microlines
Spectre 150 microlines
Sabre2-120 microlines
Sabre2-135 microlines
Saber2-150 microlines
Heatwave 120 microlines
Heatwave 135 HMA w/ H-mod
Heatwave 150 microlines
Crossfire2-149 vectran
Safire-129 microlines
Vengeance 120 microlines
Mojo 240 dacron
Troll DW MDV 265 dacron
Blackjack 280 CUS dacron
Ace 280 dacron
Parafoil 252
Raven2-218 microlines (as a main)
PDR160 (reserve ride) microlined
Stiletto 135 microlines
Stiletto 120 microlines
Sabre-170 microlines
Cobalt 135 microlines and H-mod

FWIW My favorite by far has been the Spectre 120 w/ dacron :)
I am 180lbs + gear

[Baksteen 84]

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Yes, I need to demo a Storm. It may be the best of both worlds; it was certainly designed as such and is definitely marketed as such.

That can be arranged.

"That formation-stuff in freefall is just fun and games but with an open parachute it's starting to sound like, you know, an extreme sport."
~mom

[Andy_Copland 0]

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But instead of pointing out what those good reasons are for using a 9-cell over a 7-cell, which would have been helpful to the person trying to make that decision, you got yourself so worked-up over an obviously facetious comment, that all you could think to do was respond with an insult.

Yea, because your comment was really technical

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All the cool people jump 9-cells. You want to be cool, don't you?

Really helpful stuff. Keep on digging.

1338

People aint made of nothin' but water and shit.

Until morale improves, the beatings will continue.

[likestojump 3]

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Lighten up lad

No, he always posts crap like that. Just because hes an old dinosaur who can't hold a candle to skydivers these days he tries to belittle people with what he thinks is his "ace" card just because he jumped in DaVinci's time.

For a change somebody ELSE is the 'Old Fart'!



Other than that Andy, I dunno if I'd agree with your opinion...

John jumps for a main, a big 7 cell and a spring loaded pilot chute...you know like reserves!

He jumps a lot, is current, proficient, safe and I don't hear about alotta cutaways or injuries from him...that's actually the kind of 'candle holder' some of the 'skydivers today' might need around.
Ya know...you may not agree with the conservative mindset a lot of us old farts have, but you gotta admit if a guy can jump regularly for 30 years and not have a limp, he just may be on to something!

hey, my DZO has been jumping since 1964, has over 6000 jumps, is Master Rigger, Commercial Pilot, and a nice guy. He jumps a 9cell 104 canopy loaded at about 2.0 in a container with a BOC.
he has never been injured either, and without trying to be sarcastic he is quite conservative as well. Oh, he doesn't limp either.

just another data point....

[airtwardo 7]

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Lighten up lad

No, he always posts crap like that. Just because hes an old dinosaur who can't hold a candle to skydivers these days he tries to belittle people with what he thinks is his "ace" card just because he jumped in DaVinci's time.

For a change somebody ELSE is the 'Old Fart'!



Other than that Andy, I dunno if I'd agree with your opinion...

John jumps for a main, a big 7 cell and a spring loaded pilot chute...you know like reserves!

He jumps a lot, is current, proficient, safe and I don't hear about alotta cutaways or injuries from him...that's actually the kind of 'candle holder' some of the 'skydivers today' might need around.
Ya know...you may not agree with the conservative mindset a lot of us old farts have, but you gotta admit if a guy can jump regularly for 30 years and not have a limp, he just may be on to something!

hey, my DZO has been jumping since 1964, has over 6000 jumps, is Master Rigger, Commercial Pilot, and a nice guy. He jumps a 9cell 104 canopy loaded at about 2.0 in a container with a BOC.
he has never been injured either, and without trying to be sarcastic he is quite conservative as well. Oh, he doesn't limp either.

just another data point....

Who's your DZO?

~ If you choke a Smurf, what color does it turn? ~

[wmw999 2,439]

If a statement pisses you off, far fewer people will read it if you just ignore it or post something factual to counter it, than if you start a shitstorm.

Then people go to look up the original comment. They might not think that the original comment deserves the reaction it got.

Either way, shitstorms just get shit all over people instead of making them sound smart and insightful, or making whoever they're attacking sound stupid.

And I've jumped both 7 and 9-cell canopies. They're tools.

Wendy P.

There is nothing more dangerous than breaking a basic safety rule and getting away with it. It removes fear of the consequences and builds false confidence. (tbrown)

[popsjumper 2]

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John you're so full of shit. I jump a 7 cell and 9 cell depending what im doing, and never is the 9 cell because its fucking "cool."

Andy, John's sarcasm blew right over your head. Did you hear the loud whooooosh?

Obviously not because you went on to make a complete ass out of yourself.



Pointless to stop now, though....the hole you've dug couldn't possibly get any deeper. But it's all good...there's somebody else in the hole with you. Ya'll have fun!

My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239

[likestojump 3]

Andy and I will gladly stay in our hole. It's nice and cosy here.

I bet the dude with 110 jumps really understood the sarcasm in John's response, and appreciated it.

[ladydyver 0]

soooo.....here is my perspective....baby jumper and all.

i loved flying my spectre (7 cell) but couldn't land her worth a darn....was I buffaloed by my canopy....distinct possibility. Switched to my pilot
and i love my pilot.....and have continued jumping pilots since. my experience is limited but i found a canopy that suits me......and that is what you should do ----demo. demo. demo. find what fits you and what you want to achieve with jumping. In the meantime...enjoy the banter, I always love hearing from people with more experience as they have more knowledge than I to draw from. this is my token 2 cents...not sure it is even worth that much.

DPH # 2
"I am not sure what you are suppose to do with that, but I don't think it is suppose to flop around like that." ~Skootz~
I have a strong regard for the rules.......doc!

[JackC 0]

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Andy, John's sarcasm blew right over your head. Did you hear the loud whooooosh?

DZ.com should come with a health warning, especially when the advice given here is actually sarcasm.

[virgin-burner 1]

discussions like the ones above are the main reason why i never ask a question on here..

but its all good, i'm a 200-jump-jockey and i know EVERYTHING there is to know about skydiving anyway..

“Some may never live, but the crazy never die.”
-Hunter S. Thompson
"No. Try not. Do... or do not. There is no try."
-Yoda

[popsjumper 2]

My apologies for hijacking.
You may not know that I know Andy_C fairly well and we are friends. We can razz each other and know where we are coming from with no ill feelings.

I should have done that through PM instead of publicly in this thread.

As far as the OPs question, I have no input since 95% of my jumps have been on 7-cell and I don't have enough experience with 9-cell to make an intelligent assessment of the differences. I could only repeat what I've been told. Sorry, OP.

My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239

[Rick 67]

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soooo.....here is my perspective....baby jumper and all.

i loved flying my spectre (7 cell) but couldn't land her worth a darn....was I buffaloed by my canopy....distinct possibility. Switched to my pilot
and i love my pilot.....and have continued jumping pilots since. my experience is limited but i found a canopy that suits me......and that is what you should do ----demo. demo. demo. find what fits you and what you want to achieve with jumping. In the meantime...enjoy the banter, I always love hearing from people with more experience as they have more knowledge than I to draw from. this is my token 2 cents...not sure it is even worth that much.

my first canopy was a Sabre 1 put about 300 jumps on it and then switched to a Spectre. I like the ease of packing and the openings a lot better and it was more responsive (that could be jsut because it is smaller) but I biffed in for about 20 landings until I figured out how to land the damn thing. A few hundred jumps later I still love the 7 cell it is great for demo's and tight landing areas's

my .02

You can't be drunk all day if you don't start early!

[d123 1]

Just another data sample in the 7 cells frenzy
I had biffed only one landing out of around 100 jumps on my Spectre due to the noob cross wind reaching thingy (a.k.a. the last second wind gust )
All the others have been stand up. I've done downwind, nowind, cross wind, flare turns, landings in really really tight spots and more. I LOVE ZEE SPECTRE. Its a versatile tool that will help you discovering new and interresting things(back risers, front rises, combinations of those with toggles and yourself feeling the wing). The Flare is powerfull and you can easily pop-up if you go too fast. Back risers landings are not chalanging at 1:1 WL.
1st jump on it got it stand up. 1st cross wind got it biffed 1st reserve ride after Spectre experience was a stand up.
Now, I'm trying 9 cellz just to see the other side!

Regards,
Jean-Arthur Deda.

Lock, Dock and Two Smoking Barrelrolls!

[uscallesen 0]

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Does anyone jump A 7 cell canopy?.Was wondering the differences between A 7 cell and A 9 cell.I do not see many 7 cells.Thanks Blues.

I have 90 jumps on 9 cells (50 in student/Navigator and 40 in a sabre1-170) and 10 jumps on my brand new Storm-170.

I've noticed two things in particular going from the Sabre1 to the Storm - The flare is VERY different on the Storm - instead of giving me a good swoop like my Sabre1 it tends to break and lift instead. I get very soft touchdowns on the Storm - (Actually miss the high speed of the Sabre during landings)

The other thing is stability in turbulence - The Storm behaves much better than the Sabre - fells more steady in situations where the Sabre would get "wobbly"

I almost forgot... the opening are VERY different - no matter how poor I pack it I get soft gentle openings which was my main reason for buying the Storm in the first place.

[Baksteen 84]

How do you flare your Storm?

"That formation-stuff in freefall is just fun and games but with an open parachute it's starting to sound like, you know, an extreme sport."
~mom

[uscallesen 0]

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How do you flare your Storm?

I perform the flare pretty much the same way as on my Sabre - bring the toggles down until I fell the input beginning to affect the downward speed - then adding more flare as the ground approaches - I usually end up hovering 15cm above the ground and can simply "step down" to complete my landing.

I did flare a little late on my first few jumps - was pleasantly surprised by how much power is left at the end of the flare.

[Lenzo 0]

Thanks everyone who posted recieved the info I was looking for.John I know it seems silly but I am the newbie with A 130 jumps and just trying to learn sorry if this was discussed a while ago.

Smile,pull,land