Calculating pack volume

[gus 1]

For any canopy design and size the manufacturers must know how much fabric they need, how much stitching is required and the total length of line used. Isn't this enough to calculate the volume of material used to manufacture the canopy? It wouldn't give you the typical volume of a packed canopy (you'd never squeeze all the air out) but would it give you an accurate means of comparing the volume of 2 canopies?

Gus

OutpatientsOnline.com

[NightJumper 0]

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Isn't this enough to calculate the volume of material used to manufacture the canopy?

Actually the way that we measure finished canopy volume is to place the canopy in a cylinder and measure the actual volume.

[mjosparky 3]

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Isn't this enough to calculate the volume of material used to manufacture the canopy?

Actually the way that we measure finished canopy volume is to place the canopy in a cylinder and measure the actual volume.

And that volume can vary from day to day and from canopy to canopy of the same type.
Sparky

My idea of a fair fight is clubbing baby seals

[darkwing 4]

My answer is "No". The volume of a canopy depends on more factors than that, as implied by the way it is actually measured (as mentioned above). Different rolls of the "same" fabric can pack differently. Minor tension differences, or seams sewn by different people can result in volume changes. While you could get an answer using your method, it wouldn't be as good as actually measuring it. One thing that most jumpers don't have a grasp of is how much a canopy can deviate from the stated pack volume. This can be due to humidity, packing method, number of jumps on the canopy, and other factors.

-- Jeff
My Skydiving History

[fstz28 0]

where can one look to see the different effects that humitdity, dz altitude from state to state, and such have on canopies.