Best test to analyse the parachute stability...

[Manoel Victor]

What the best test to analyse for exemple a parachute stability for a rocket of 13 kg? Maybe drop from very high place? Wind Tunnel? Please, I need suggestions and how to do it properly. Thanks!!!

 

[Steve Shannon]

I would just fly it.

 

[Manoel Victor]

What do you think about drop a 13kg backpack with sand and the parachute from a 30m build?

 

[Manoel Victor]

I'm just saying this because someone told me that

 

[Steve Shannon]

There’s nothing wrong with that, but depending on how quickly the chute opens you might not really learn anything about its stability. Make a small scale chute and fly it on a simple rocket.

 

[TimothyG]

Sometimes if you live near a school with a flight program you can talk a student into throwing a data package out of the plane under chute for science. I’ve had pretty good luck so far.

 

[Manoel Victor]

Sometimes if you live near a school with a flight program you can talk a student into throwing a data package out of the plane under chute for science. I’ve had pretty good luck so far.

What do you think to drop a 13kg from a 30m build?

 

[Manoel Victor]

There’s nothing wrong with that, but depending on how quickly the chute opens you might not really learn anything about its stability. Make a small scale chute and fly it on a simple rocket.

ah ok! Do you know any good and simple test to do for a open test?

 

[Steve Shannon]

Fly it in a rocket with an altimeter and look at the data.

 

[Mr Rocket]

Fly it in a rocket with an altimeter and look at the data.

To be more specific, fly with a recording altimeter that records the entire flight, NOT apogee only. This way you will see descent speed, as well as any fluctuations in descent speed. By observation, you will be able to note any oscillation of the chute.

 

[jazzviper1]

Most research on parachute stability has already been done. A conical type would be the simplest to construct, just make a 12 gore flat canopy but leave 2 gores out. That should get you the stability that you want without too much trouble. The long answer is there are a lot of factors that can affect parachute stability, shape being only one of them. Suspension line length, line count, distance between load and canopy, etc. Drop tests can help but for clear results indoor drop tests would be best. This eliminates air currents as a factor, this can be a big problem near structures.

 

[BABAR]

Ummm, what’s the goal?

If the goal is simply to safely recover a 13 kg rocket, why the emphasis on “stability”

 

[Manoel Victor]

The goal is just bring the rocket safety.

 

[BABAR]

I think OpenRocket and RockSim can probably give you appropriate chute sizes for your rocket. I don’t think stability will be much of an issue.

What is your rocket diameter and how long is your space for chute packing?