Dual descent rate on one toroidal chute?

[Adrian A]

I have been making and using small toroidal chutes for a few years now, and one interesting thing about them is that you can greatly affect the drag of the chute by how much the center line is pulled down relative to the shroud lines on the perimeter. And if you pull only on the center line, the chute is just a bunch of loose nylon flapping in the wind. Has anyone used this to get a drogue and a main using one chute and a line cutter that would release extra length on the center line?

 

[dhbarr]

I had toyed with the idea of slowly paying out the center line to allow gradual slowing, but never more than a napkin sketch.

 

[Cameron Tinder]

I have a 4" rocket setup to do just that, but I have been too busy making stuff to find time to fly it! But rather than using a Piranha cutter to release the apex, I have it setup with the TD-2 to release it so that I would not have to make a new riser every time this thing got flown. Also, instead of using a "toroidal" type chute, I have it set up with a standard conical chute. Reason is that with the toroidal chute (Iris Fruity Chute) there seems to be too much "stuff" that is below the skirt of the chute when it is reefed to the point where there is little drag. The concern is that it looks like it would increase the odds of fouling the chute when the apex gets released. With the conical chute, testing has shown this to be of little concern. This said, I plan on testing/flying this setup with the Iris Ultra chute as well

And FWIW, there will soon be a TD-1 tether and release device that would be well suited for this task!

 

[cls]

Would a regular choke ring work as well? I never tried that on a toroidal chute.

 

[Adrian A]

I have a 4" rocket setup to do just that, but I have been too busy making stuff to find time to fly it! But rather than using a Piranha cutter to release the apex, I have it setup with the TD-2 to release it so that I would not have to make a new riser every time this thing got flown. Also, instead of using a "toroidal" type chute, I have it set up with a standard conical chute. Reason is that with the toroidal chute (Iris Fruity Chute) there seems to be too much "stuff" that is below the skirt of the chute when it is reefed to the point where there is little drag. The concern is that it looks like it would increase the odds of fouling the chute when the apex gets released. With the conical chute, testing has shown this to be of little concern. This said, I plan on testing/flying this setup with the Iris Ultra chute as well

And FWIW, there will soon be a TD-1 tether and release device that would be well suited for this task!

Cool! I'll be very interested to hear how this goes.

 

[pugachu]

my 38mm min diameter rocket is setup like this. I have loops sewn into the shock cord between the cutter and the apex line, so the apex line doesn't get tangled in the shock cord. I can take pictures of the setup when I get home. I've only flown it once like that, but it did work.

 

[pugachu]

Hi Adrian,

This is my setup for HED style on my 38mm min diameter rocket.
The blue strips are nomex loops, sewn to the kevlar harness. The thinner kevlar thread goes to the apex of the 'chute. It is attached to a cable cutter, near the attachment point to the nose electronics bay. It's flown like this once, and worked, but i have to be careful when packing, to ensure it doesn't tangle.

 

[pugachu]

The funny thing is that I am debating on going towards a drogueless/'chute cannon setup like you do for the next iteration of my min diameter rockets..