# Clustered 'chute descent rates?

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#### mkmilion

##### Well-Known Member
I was curious as the descent rate of two or more 'chute equal a single 'chute.
For example: Does (2) 12" 'chutes = (1) 24"?
Or (3) 8" = (1) 24"
ETC.
The reason I ask is that I don't currently have a 24" and have alot of 12". 2 cents always welcome.

Ed

I have no real idea, but I am going to venture a guess.
No.
I'm thinking it is the total area of the chute that you need to consider.
The area of a 24" chute in square inches is 452.blah blah blah.
The area of a 12" chute is 113.yadda yadda yadda.
So two 12" chutes have 226.something.
Looks to me that you would need 4 12" chutes to equal one 24 incher.
Which would make sense with the whole squares thingee.
Unless of course I'm wrong, in which case you are actually dreaming and this was never written and I've been right the whole time since it was never posted.

Now, let's see who busts me out.

Greg

I found the formulas for a octagon and a hexagon I just don't remember the length of a side of a 24" 'chute. And is it an oct or a hex?

Originally posted by 11Bravo
I have no real idea, but I am going to venture a guess.
No.
I'm thinking it is the total area of the chute that you need to consider.
The area of a 24" chute in square inches is 452.blah blah blah.
The area of a 12" chute is 113.yadda yadda yadda.
So two 12" chutes have 226.something.
Looks to me that you would need 4 12" chutes to equal one 24 incher.
Which would make sense with the whole squares thingee.
Unless of course I'm wrong, in which case you are actually dreaming and this was never written and I've been right the whole time since it was never posted.

Now, let's see who busts me out.

Greg

Ya dun good.

But one other issue to consider: if you have chutes next to each other, they're going to be at an angle when they open, not perpendicular to the ground. So, they'll spill air. How much depends on how much they're tilted, and that depends on size, shroud length, etc.

I suppose you could always experiment with cutting chutes at an angle as it were, kind of off center, so they caught more air despite being at an angle.

Or you could tie several feet of kevlar cord to the end of the shock cord, tie loops in it every couple feet, and bring a big bird down on four or five 12" chutes in series.

I did speak about this to al old-dog rocketeer and his respomse was:

If I want to do macrame, I can sit on my couch, I don't need to shoot it 2000 feet straight up...

A

The area of a 12" hexagonal parachute is: 93.5279999......." sq.
The area of a 24" octagonal parachute is: 695.232" sq.

Thus the number of 12" hexagonal parachutes to equal the same amount of surface area of 24" octagonal parachute is: 7.4334103156274056966897613548892 so about 7.

mkmillion - how did you measure those polygons, apex-to-apex, or side-to-side? makes a difference for the area calculation ...

I got lazy and found an online area calculator that figures it out by how long the side is. I fail geometry 4 times in high school, so the internet had to have my back on this one.

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