7 Cell or 9 Cell

[jclalor 12]

Was just wondering the differences in a spectre or storm against a 9 cell, in particular the glide rate and landings.

[OlympiaStoica 0]

Quote

Was just wondering the differences in a spectre or storm against a 9 cell, in particular the glide rate and landings.

I'm no rigger and a novice to the sport just like you, so I'll refrain from discussing any technical aspects, but I'll relay my limited personal experience.

Right off student status I started jumping a Safire 2 (9-cell) - fun to fly, but I hated the openings and I could never figure out the timing of my flare. I gave up on it after 25 jumps or so and bought a Storm (7-cell) - worked much better for me. (Sure I broke my ankle on it, but the canopy had no bearing on the accident - with a low turn and no flare I would have hurt myself on any canopy.)

The major difference I noticed, beside the much better, consistent openings, was the glide - with the Safire 2 I had a lot more forward movement; with the Storm, if I got a little bit of wind, when I face into it I come straight down (very steep angle).

O

[NiteQwill 0]

I agree with the above. With my Spectre, if I face into the wind, I end up with a very steep angle. Otherwise, the soft and head-on openings, I can't complain.

"Fail, fail again. Fail better."
-Samuel Beckett

[Andy0689 0]

I have found PD's canopy "Flight Characteristic" documents about their canopies are very accurate. I just returned a demo Spectre and am flying a new-to-me Sabre2. I flew both canopies within a few days of each other. Both descriptions of the canopies are very accurate so I imagine the same holds true for the other canopy descriptions.

If you haven't tried it yet, the PD demo program is a pretty good deal. Very easy to sign up. I got a call within a couple of hours of signing up on the web.

7 Cells
PD Storm
PD Spectre

9 Cells
Sabre2
PD Pulse

Andy
I'll believe it when I see it on YouTube!

[Andy9o8 2]

I jump a Pilot (9-cell), which I love; but my next canopy will probably be a 7-cell (Spectre or Storm) with Dacron lines, as my middle-aged spine really needs softer openings these days.

9-cells have a shallower glide angle, so they'll get you back to the DZ from a long spot better than an intermediate-level 7-cell will do. They're also generally snappier in turns, have more forward drive and tend to have a more powerful flare than 7-cells (although modern 7-cells are tuned to compensate for this somewhat).

Spectre and Storm have consistently soft openings. (My Pilot usually does, too; but sometimes it's brisk.) Try not to doze off waiting for the Spectre to finish its snivel. They're less twitchy than intermediate-level 9-cells, making them slightly more forgiving of minor piloting mistakes. They also land well, but you come in at a steeper angle. This characteristic can come in handy if you find yourself needing to land in a very tight area (like an off landing) and have less than highly-experienced piloting skills.

[erdnarob 1]

I have jumped mains with 5 cells (Sratostar,Cirrus), 7 cells (Stratocloud, Cruisair, Spectre...) and 9 cells (Nimbus, Safire, Sabre..., Sabre 2, Nitro, Nitron, Katana, Firebolt) and I can tell that given the size, the flare is more powerful on a nine cells. The 9 cells parachute is also generally a better glider than a 7 cells since the aspect ratio is larger (just like actual glider wings). That means (provided you have the technique) you will come back from a further bad spot with a nine cell and will land more softly. Since the 9 cells is a better glider, your approach will be more flat while a 7 cells descent is more vertical. What speed hurts the most when getting in contact with the ground ?..the vertical one. Now if you look at birds, which ones are landing the most gracefully, the ones with short wings or wide wings. Look at a seagul or a wild goose landing and that will give you an idea of what parachute to choose (Small or large aspect ratio). The aspect ration is the span divided bu the chord of the parachute. For instance the aspect ratio of the 7 cell Storm and Spectre is 2.14 to 1. For 9 cell Sabre 2 it is 2.58 to 1; for 9 cell Katana it is 2.74 to 1, and for a PD reserve it is 2.1 to 1. But I was told that the Storm is a 7 cell flying like a 9. Sorry, I didn't jump it already.
I talking here in general without consideration of the jumper status.

Learn from others mistakes, you will never live long enough to make them all.

[Parafoil27 0]

Sorry to hijack the thread but what lines did the
"PD 9 cell" canopies come with?

EARTH! Short bus of the universe,
since the year T+10.3 billion!

REV. DUDEMIESTER D.S.#120

[Gato 0]

Mine came from the factory with Spectra - I think most of them do.

T.I.N.S.

[erdnarob 1]

I agree, this is Spectra (microline) made of polyethylene fibers for PD 190 (F111) or other sizes. Generally HMA lines (which are more expensive) are for fully elliptical canopies to keep the differential trim stable. Those canopies are very sensitive when out of trim. Amazingly, Spectra lines shrink due to the friction especially the outside ones.

Learn from others mistakes, you will never live long enough to make them all.

[Parafoil27 0]

For some reason spectra was sticking in my mind but i wasn't sure . Thanks !

EARTH! Short bus of the universe,
since the year T+10.3 billion!

REV. DUDEMIESTER D.S.#120