Why....

[billvon 2,426]

>I f I remember correctly, the Set 400 is made that way, but I think two
>cells on each end are tri chambered.

So that would be a 22 cell!

[JohnRich 4]

Quote

I would call those mutated cells!

Hmmm, we could call it cell division, or mitosis: one cell is dividing and creating new cells. Just like in biology class.

It... is... ALIVE!

[JohnRich 4]

Quote

Look at the picture of that 7 cell 16 chamber thing....just the top skin. You can see 7 very distinct cells. In between the loaded ribs the top skin just domes up, the chambers aren't doing much other than pulling the bottom skin up with it, now look at the Velocity....in between the line attachments (on the top skin) it doesn't dome up, because the crossbracing is also loaded. so looking at just the top skin you see 21 very distinct cells.

So where are we on a good definition of a "cell"?

Is a "cell" a segment that is bordered on both sides by support, either by lines or by cross-bracing?

And why should "support" be a distinguishing characteristic in the definition?

I wonder what the official definitions of "cell" and "chamber" are?

My Poynter "Parachute Manual" is too old and doesn't have it.
My Knacke "Parachute Recovery Systems Design Manual" doesn't have it.

Hey, I found it!:

"Basic Performance, Design and Construction of Ram-Air Inflated Gliding Parachute Wings", by Manley Butler, 1986, Naval Weapons Center, China Lake, CA:

Cells: Cells are the compartment formed by the upper and lower surfaces and two adjacent load bearing ribs. Each cell is usually divided by a non-loadbearing rib to form two half-cells. Cells are numbered left to right by full-cell number; use left (L) and right (R) to designate the appropriate half-cell.

The "Standardized Nomenclature for Ran-Air Inflated Gliding Parachute Wings" has been previously published by the U.S. Parachute Assoc. and the Parachute Industry Assoc. with help from the Aerosystems Dept.

There you have it - an official definition. So the support lines do matter, as the delineation edges for definition.

So a three-chamber cross-braced cell could be called three cells, because each chamber is bordered by a support rib. Whereas the regular two-chamber cell has a non-loadbearing rib in the center, which doesn't count per the definition, so those two chambers are only one cell.

It's all semantics...