Question on canopy opening malfunctions?

[jrcolo 0]

Is there a significant difference on opening malfunctions when you compare moderate (1.1) but equally loaded canopys as far as the type of canopy your flying?
7 cell vs. 9 cell,Zp vs F111,etc,etc.

[darkwing 4]

I believe it is conventional wisdom among the learned that higher aspect ratio = more malfunctions. Also, more elliptical = more malfunctions. But I'm not sure I understand your question.

-- Jeff
My Skydiving History

[riggerrob 558]

Number of cells: 7-cells are slightly more reliable than 9-cells.
That is why most BASE and reserve canopies are rectangular (not tapered) 7-cells.
With the exception of 7-cell Diablos - which have the highest rate of spinning malfunctions - but Diablos are no longer in production.

Type of fabric makes little difference.
It is more question of fabric condition ( 1 jump versus 1,000 jumps?)
As parachutes wear out, they malfunction more often.

Generation is more important than type of fabric. However, most F-111 canopies are older designs, which mal slightly more often.

Line condition is probably the most important determination of malfunction rates. Shiny new lines mal far less often than tired old lines.

The bottom line is that when comparing modern canopies (Hornet, Pilot, Sabre, Safire, Spectre, Triathlon, etc.) - that are designed to be loaded around 1.1 - line condition and packing technique have greater influence on malfunction rates, than canopy model.

[JohnMitchell 14]

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Generation is more important than type of fabric. However, most F-111 canopies are older designs, which mal slightly more often.

1200+ jumps on a couple of original Units, never chopped a single one. The old designs were the low aspect ratio, 7 cells, like what you said were the most reliable. And we never had to chop because of line twists.

[ryoder 1,396]

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Generation is more important than type of fabric. However, most F-111 canopies are older designs, which mal slightly more often.

1200+ jumps on a couple of original Units, never chopped a single one. The old designs were the low aspect ratio, 7 cells, like what you said were the most reliable. And we never had to chop because of line twists.

Units were also unique in that they had no "D" lines; Fewer lines to tangle.

"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

[ryoder 1,396]

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With the exception of 7-cell Diablos - which have the highest rate of spinning malfunctions - but Diablos are no longer in production.

It was my first non-square. Isn't really elliptical;
Just a straight taper on the trailing edge like a Cessna wing.
It gave me 60 nice non-eventful openings until one day...
I had no idea a canopy loaded at only 1.2 could spin like that.

"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

[JohnMitchell 14]

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Units were also unique in that they had no "D" lines; Fewer lines to tangle.

And no cascades, either. All lines went down to the links. Made planing a stack a cinch. Plus, they opened soooo softly. Vskydiver jumped one until she was 7 months pregnant, no problems.

[ryoder 1,396]

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Units were also unique in that they had no "D" lines; Fewer lines to tangle.

And no cascades, either. All lines went down to the links. Made planing a stack a cinch. Plus, they opened soooo softly. Vskydiver jumped one until she was 7 months pregnant, no problems.

Speaking of soft openings, the one I had was purchased used from the original owner who had vented the slider to speed up the openings. I've never seen a slider vented to such an extreme. It was pretty much all vent with a little strip of webbing around the perimeter. Had I not watched him make many jumps on it, I would have been very leery of jumping it with that slider.

"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.