Just curious, has anyone ever used a drogue chute and combined it with a JLCR on the main? Kinda like dual deploy, with the JLCR on the main?
Thanks.
Thanks.
JLCR and Drogue chute
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Yeppers, I do this on all of my larger rockets.
Thanks for the response! I'm assuming drogue tied to nosecone, main/JLCR tied a foot or so down the shock cord?
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Just make sure your attachment point for the main do not have your NC banging into your airframe.
MidOH
Well-Known Member
Shouldn't need one with a lightly built Zephyr.
Drogue location is important. I'd prefer closer to the booster.
Drogue location is important. I'd prefer closer to the booster.
waltr
Well-Known Member
The drogue could serve two purposes:
1- set a lower descent rate than would be without. This can reduce stress when main chute opens.
2- Controls the attude of the booster verse nose section and keeps some tension on the cords. This helps prevents tangling the main when it is released.
1- set a lower descent rate than would be without. This can reduce stress when main chute opens.
2- Controls the attude of the booster verse nose section and keeps some tension on the cords. This helps prevents tangling the main when it is released.
This sounds interesting to me, I have several larger rockets that aren't DD and I use a JLCR with. So people are just adding a drogue between the NC and the main? Anyone have any pictures of the setup, just want to make sure I am imagining this correctly, as it makes good sense.
I only have two rockets I use a JLCR with, but the chute bundle acts like a drogue on both of them and the rockets comes down fast, fins first, and the nose cone stays below the chute/JLCR bundle. I wouldn't want a drogue to slow it down. Dropping faster is better IMO.
There's lots of good drogue threads on the forum to read through. Like a lot of things in rocketry, there's no shortage of opinions 
What I do with my JLCR is attach the drogue midway between nose cone and body tube. Then the JLCR and Main attach directly to the nose cone, this has the side effect of making it easy to turn the JLCR on because i just have to pull the nose cone out a few inches, hit the button, and put it back. Last weekend I did a drogue-less deployment where the setup was identical but no drogue parachute. Worked fine.
I'm of the _opinion_ the main purpose of the drogue is to stabilize things on the way down. On my 4" cardboard DX3, once the propellant mass is gone, and the nose cone separates, it basically fin stalls and falls horizontally nice and slow. The drogue chute (12") puts the falling airframe in a very shallow upside down V orientation. That, in my opinion, is the best orientation coming down in prep for main deployment. I also have a 4" fiberglass build I did for an L3 certification and the orientation on descent was the same. The descent rate was a little faster because it's heavier but it was still setup very well for main deployment.
PS another note about that 4" cardboard dx3 (i love that kit btw and highly suggest it). On my first L1 attempt, my youngest son disconnected the shock cord while i was prepping because he was "helping" The body tube floated down horizontally and landed with no damage. Obviously I didn't get the cert, but i was surprised how slow it fell, it seemed to float down. Fat body tubes falling horizontally produce significant drag and fall very slowly.
What I do with my JLCR is attach the drogue midway between nose cone and body tube. Then the JLCR and Main attach directly to the nose cone, this has the side effect of making it easy to turn the JLCR on because i just have to pull the nose cone out a few inches, hit the button, and put it back. Last weekend I did a drogue-less deployment where the setup was identical but no drogue parachute. Worked fine.
I'm of the _opinion_ the main purpose of the drogue is to stabilize things on the way down. On my 4" cardboard DX3, once the propellant mass is gone, and the nose cone separates, it basically fin stalls and falls horizontally nice and slow. The drogue chute (12") puts the falling airframe in a very shallow upside down V orientation. That, in my opinion, is the best orientation coming down in prep for main deployment. I also have a 4" fiberglass build I did for an L3 certification and the orientation on descent was the same. The descent rate was a little faster because it's heavier but it was still setup very well for main deployment.
PS another note about that 4" cardboard dx3 (i love that kit btw and highly suggest it). On my first L1 attempt, my youngest son disconnected the shock cord while i was prepping because he was "helping"
The body tube floated down horizontally and landed with no damage. Obviously I didn't get the cert, but i was surprised how slow it fell, it seemed to float down. Fat body tubes falling horizontally produce significant drag and fall very slowly.
