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AfterBurners

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I never worked with dual parachute before as in having a separate chute for the nose cone and one for the body.

What is the best practice to pack the chutes so they don't get tangled on ejection?

Also how long of a leader line would I need on the nose cone. I was thinking maybe 3 feet should work to keep the chute centered over the nose cone.
 

djs

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Are you talking about dual deploy, or two chutes that come out at the same time? Which rocket/kit is this for?
 

djs

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I do this on my Estes Chuter two. No connection between the two pieces. Nose cone is attached to just the chute (no shock cord). I put the booster chute in first (above the wadding), then the upper chute above it. Seems like a mess, but everything comes out ok with no tangles.
 

rharshberger

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Certain rockets that use two chutes recommend putting the upper chute in first ( nose cone for example) then the lower ( airframe chute) that way if one comes out the other is likely to as well. Wadding of course goes in its usual spot.
 

jrkennedy2

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Certain rockets that use two chutes recommend putting the upper chute in first ( nose cone for example) then the lower ( airframe chute) that way if one comes out the other is likely to as well. Wadding of course goes in its usual spot.
+1 The AT Astrobee-D kit does well using this method.
 

markkoelsch

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If it were me, I would think a free bag sort of arrangement.

Main chute in a nomex blanket or bag. The bag is attached to the nose cone and chute. Ejection happens pushing it all out. The nose cone parachute inflates pulling the nose cone and bag free leaving the main to inflate.

Both chutes are protected. Tangling is minimized or eliminated.
 

AfterBurners

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I'm actually thinking about using dual chutes on my Madcow 4" Patriot, since the nose cone comes in at 33oz I would hate to have it slam back into the air frame and ruin the rocket and L2 cert flight, but finding this wouldn't be such a bad idea to apply on most card board type rockets that have a fairly good amount of nose weight in them to make stable. I was reading a review in EMMR of someone who built a Madcow Jayhawk and the nose cone slammed back into the tail cone and just dinged it up really bad. I'm sure there were some circumstances that could have caused this, but I figure as much time I put in to building these kits or rockets I don't want to destroy them or do I want to rebuild if that can be avoided. I want to fly them and get as many flights as possible.. I want them back with as little damage as possible.
 

Coop

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If it were me, I would think a free bag sort of arrangement.

Main chute in a nomex blanket or bag. The bag is attached to the nose cone and chute. Ejection happens pushing it all out. The nose cone parachute inflates pulling the nose cone and bag free leaving the main to inflate.

Both chutes are protected. Tangling is minimized or eliminated.
This would be my recommendation as well. Sizing the pilot to recover the nosecone, deployment bag, and whatever else is attached to it to achieve the same descent rate as the booster gets the two pieces landing in the same approximate area.

Just me sure to run both sets of values--NC set and Booster set (less everything still attached to NC). You may find you can drop the size of your main and still have a safe landing speed.

Later!

--Coop
 

Handeman

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This would be my recommendation as well. Sizing the pilot to recover the nosecone, deployment bag, and whatever else is attached to it to achieve the same descent rate as the booster gets the two pieces landing in the same approximate area.

Just me sure to run both sets of values--NC set and Booster set (less everything still attached to NC). You may find you can drop the size of your main and still have a safe landing speed.

Later!

--Coop
This is what I did with my 6" rocket. The difference is that I put 100 ft. of 150 lb Dacron with taped z-folds in the d-bag. It's attached to the d-bag and the apex of the main chute. The pilot chute and nose cone are designed to drop about 5 ft/sec slower then the main. The Dacron line keeps the two connected and the difference in speed keeps the nose cone and pilot above the main.

The last flight, fourth using this method, was when I flew "Kate" at LDRS and there was still a taped z-fold in the Dacron line that never tore the tape or pulled loose.
 

Coop

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This is what I did with my 6" rocket. The difference is that I put 100 ft. of 150 lb Dacron with taped z-folds in the d-bag. It's attached to the d-bag and the apex of the main chute. The pilot chute and nose cone are designed to drop about 5 ft/sec slower then the main. The Dacron line keeps the two connected and the difference in speed keeps the nose cone and pilot above the main.

The last flight, fourth using this method, was when I flew "Kate" at LDRS and there was still a taped z-fold in the Dacron line that never tore the tape or pulled loose.
Interesting... as the pilot with its slower descent rate will keep the NC up above the main as it's being tugged down.... Is the NC where Kate lives? Has this got you better signal from Kate? I think it's a fascinating system, just way out of my price range.


Later!

--Coop
 

AdAstraPerAspera

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Certain rockets that use two chutes recommend putting the upper chute in first ( nose cone for example) then the lower ( airframe chute) that way if one comes out the other is likely to as well. Wadding of course goes in its usual spot.
I did this on my L-3, worked great. Of course this was the low altitude portion of a dual deploy setup. If you don't want to do a deployment bag, this is the way to go.
 

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