Using Chute Release to reef a parachute?

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neil_w

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I was idly pondering if it would be possible and/or desirable to employ a Chute Release to reef a chute rather than completely contain it. Therefore the reefed chute could act as a drogue, and then open up fully at the target altitude. This would eliminate the need for a separate drogue (for those who choose to use one), and also (maybe) some issues with trying to fold the chute properly into the CR.

My original thought was what a Chute Release would look like that was expressly design for this purpose, and then I moved on to think about exactly how you could employ an existing CR to do this.

Has anyone tried this?
 
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Steve Shannon

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I was idly pondering if it would be possible and/or desirable to employ a Chute Release to reef a chute rather than completely contain it. Therefore the reefed chute could act as a drogue, and then open up fully at the target altitude. This would eliminate the need for a separate drogue (for those who choose to use one), and also (maybe) some issues with trying to fold the chute properly into the CR.

My original thought was what a Chute Release would look like that was expressly design for this purpose, and then I moved on to think about exactly how you could employ an existing CR to do this.

Has anyone tried this?
I haven't tried it, but I think it's a very interesting idea for a larger chute. I would think you would just stretch the chute out full length and then gather the material at the mouth of the chute together for the maximum effect, or lower on the shroud lines if you want more deceleration. Wrap the chute release rubber band at that point, then just z-fold the whole works and slide it into the body tube.


Steve Shannon
 

T-Rex

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Been thinking along the same lines...

I have the 72" chute from Aerocon Systems in Fat Daddy.
https://aeroconsystems.com/cart/all-parachutes/72-inch-orange-parachute/

Originally I was going to go old school with fishing line cinching the chute skirt to be released by an altimeter/igniter which melts the fishing line. This allows the chute to act as a streamer, slowing the decent slightly. The chute could also possibly partially inflate via the spill holes around the perimeter.

That plan has several potential failure points so I bought a JLCR and intend to give it a go on my next opportunity (probably July 1st)
I figure worst case one would have to wrap the rubber band twice around to have appropriate tension. I haven't had opportunity to test yet (work gets in the way again) but hopefully will in a couple weeks.
 

Cabernut

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I remember reading about this before, cant remember where at the moment. I would also be interested in details like what band size vs chute size for a reefing setup.
 

Handeman

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I haven't had to do this. When I use the CR with my Callisto, 4" Patriot, etc. it has enough drag from the chute and nose cone that the booster comes down fins first and pretty vertical. Frankly, I wouldn't want to slow it down any be adding drag to the CR controlled chute. That would only increase the time in the air and increase the distance I would have to walk.
 

MikeyDSlagle

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Maybe use a small piece of bodytube or PVC an inch or two long split lengthwise into two pieces, put some sort of soft foam and/or rubber inside to grab the shroud lines. Then wrap the JLCR around the tube/pipe. May be better to have a washer or ring sitting on top of it, between the JLCR and the chute, so the tension from the chute trying to open will be on the washer and not the rubber band, may not be much tension, I don't know. The washer may also slow the chute opening to allow the JLCR and other two pieces to get clear of the shroud lines.

Mikey D
 

blackwing94

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I launched my 14 lb X-Celerator on a K513FJ with the main chute wrapped up in a chute release. Electronic ejection at apogee, 4200 ft. 25 ft harness with chute bundle about 5 feet from nose cone-payload bay section and 20 ft from booster section. The wrapped main provided just enough drag to keep everything falling pretty much flat. Chute opened at 600 ft. Worked perfectly. I've used drogue chutes in the past, but this worked so well I think I'm done with drogues. Cuts my black powder usage in half too.

I've had the chute release come off chutes I didn't wrap correctly (I'm still not exactly sure what correctly is) so I would vote the chute release would not stay in place in a reefed chute. That's just me feeling. You would need a longer tether to connect the chute release to a shroud line.

Someone needs to do the experiment!! Let us know how it goes. :pop:
 

OverTheTop

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I have seen big chutes (not rocketry) use a reefing ring around the shroud lines. The shroud lines rub (relatively low friction) on the ring so there is minimal wear or chance of damage leading to breakage. Maybe you could use the JLCR to hold the reefing ring, and then release it at the programmed altitude.
 

amarillo_rocket

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I havent' tried this but it might work. Place a drogue on the same shock cord as the main just make sure the drogue clears the body tube by 3ft or so. The main is attached further up the shock cord controlled by the chute release. Nose cone pops, drogue catches air, main attached to nosecone hangs below drogue then releases at the set altitude. One issue might be that the main get tangled up in the drogue. If the rocket isn't too large might be worth a try.
 

John Beans

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Wrapping Chute Release around just the base of the chute (with the rest flapping above) is what 38mm flyers have to do to get Chute Release to fit in the fuselage, since there's not room for a folded chute and Chute Release.
It's a valid technique.
But as others have noted, make sure you chute can't shake free. Use the smallest band, and make sure it's tight.
 

T-Rex

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Wrapping Chute Release around just the base of the chute (with the rest flapping above) is what 38mm flyers have to do to get Chute Release to fit in the fuselage, since there's not room for a folded chute and Chute Release.
It's a valid technique.
But as others have noted, make sure you chute can't shake free. Use the smallest band, and make sure it's tight.
Thank you for the input! (Seriously, thank you!) Some valid points have been brought up and I was beginning to wonder if it would work. Just got my unit in the mail yesterday but wont be able to fly it until probably July :( .
 
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