Tether to free bag/NC

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ericm541

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I'm considering the use of a free bag for my L3 cert, thought a nomex burrito was the simple way to go, after hearing failed attempt stories pros/cons i may change it. Only issue i have is my tracking is in the NC and i would like to tether everything, any tips on doing this?
 
If you are free-bagging, then you need two trackers. If you want to go more traditional, then here is what I did.

Traditional dual-deploy with harnesses from booster to AV bay and AV bay to NC. Standard Nomex and drogue in booster. Main in NC in a D-bag. Main chute lines attach to NC U-bolt. 36" TFR pilot chute on top of D-bag. Standard D-bag tether to top of main chute inside D-bag. I use a Fruity bag with the elastic shroud line holders on the outside, under the flap.

D-bagDD.png
 
Yes KISS is the best. Not sure why there would be failed attempt with this method. The free bag has to have a higher failure rate. I have never had a failed recovery because of using the burrito style of packing the chute.
 
If you are free-bagging, then you need two trackers. If you want to go more traditional, then here is what I did.

Traditional dual-deploy with harnesses from booster to AV bay and AV bay to NC. Standard Nomex and drogue in booster. Main in NC in a D-bag. Main chute lines attach to NC U-bolt. 36" TFR pilot chute on top of D-bag. Standard D-bag tether to top of main chute inside D-bag. I use a Fruity bag with the elastic shroud line holders on the outside, under the flap.

View attachment 335527

I use something similar, but I have the nose cone and d-bag attached to the pilot chute. When the main deploys, the pilot chute pulls the nose cone up and the d-bag out of the payload. The chute is in the d-bag, but the shroud lines are z-fold under elastic strips on the side of the d-bag. As the pilot chute pulls the d-bag up, the shroud lines pull out of the elastic first and when they are fully stretched out, the main is pulled from the d-bag. Because everything has been stretched out vertically by the pilot chute, the main opens very quickly when it's pulled from the bag.

What keeps everything together is about 100 ft of 150 lb Dacron line attached to the inside of the d-bag and the top of the main chute. The pilot chute is sized to drop the nose cone at about 13 - 14 ft/sec and the main drops the rest of the rocket at about 17 ft/sec. This means there isn't a lot of load on the Dacron line, but the pilot keeps the nose cone above the main the whole way to the ground.

L3 pilot chute.png
 
That works for me, i planned on using skyangle freebag which only has one point of attachment though. When sizing a pilot should it be for total weight of NC and bag with parachute?
 
That works for me, i planned on using skyangle freebag which only has one point of attachment though. When sizing a pilot should it be for total weight of NC and bag with parachute?

I sized mine to get the decent rate with just the weight of the nose cone. At the speed the rocket is falling and the full weight of the rocket, the pilot has plenty of drag to pull the d-bag off the main chute. After that, the nose cone is really the only thing it's got under it. The weight of the bag is insignificant compared to the weight of a 6" 5:1 spiral wound FG nosecone.
 
Yes KISS is the best. Not sure why there would be failed attempt with this method. The free bag has to have a higher failure rate. I have never had a failed recovery because of using the burrito style of packing the chute.

I've never had an issue with normal chute protector with my other setups, i'm using a skyangle cert3 Xl, which for me is huge compared to my others. I may have undersized the nomex protector for this, getting it completely wraped up is difficult, either too tight in airframe or the ends open up.
 
Back when we owned TFR we made many chute protectors for chutes larger than XL and they seemed to work out for most flyers. I just think the bag opens you up for a possible main chute failure. How are you wrapping the chute with a protector?
 
Ok, Use a good quality D bag and don't don't use a large drogue. I flew a long thin tube shaped D bag with a smallish
pilot chute on the bag (which was 36") in a 4 inch diameter rocket and the chute failed to come out of the bag!
Maybe a 48" pilot and drogue-less might have pulled it off but I'm never flying that bag again. Caught it on video too. Kurt
 
I've never had an issue with normal chute protector with my other setups, i'm using a skyangle cert3 Xl, which for me is huge compared to my others. I may have undersized the nomex protector for this, getting it completely wraped up is difficult, either too tight in airframe or the ends open up.

I use a CERT-3 XL with a 24" sq Kevlar protector in my 5" rocket and it works well. I have to make sure all the air is out of the chute and it is folded tightly before going in the burrito.
 
I use a CERT-3 XL with a 24" sq Kevlar protector in my 5" rocket and it works well. I have to make sure all the air is out of the chute and it is folded tightly before going in the burrito.

Thats exactly my situation 5" rocket,24" protector, i've mainly been practicing by rolling it in a burrito style and i have to wrap it tight. So i'm thinking could be lack of experience with a chute like this, ive already packed it a dozen times thought a bag would be a more reliable solution to keep the parachute from being damaged.
 
Thats exactly my situation 5" rocket,24" protector, i've mainly been practicing by rolling it in a burrito style and i have to wrap it tight. So i'm thinking could be lack of experience with a chute like this, ive already packed it a dozen times thought a bag would be a more reliable solution to keep the parachute from being damaged.

Are you laying the lines parallel in the chute and then z-folding it, or are you folding then wrapping the lines around the chute?
 
I've been Z-folding the chute as per the instructions lol, then Z-fold the shroud lines next to the chute and wrap it up.
 
I certed L3 using a nosecone that separated from the rest and pulled a deployment bag to deploy the main. I did it to reduce the weight of the main rocket by about 8 lbs so I didn't need so large a chute. When I deployed at 600', the nosecone landed about 20' from the rest of the rocket. No need for a separate tracker on that setup.
 
I've been Z-folding the chute as per the instructions lol, then Z-fold the shroud lines next to the chute and wrap it up.

Cannot argue with the directions. I do a slight variation like in post 4 of this thread....the lines are in the chute instead of outside.

https://www.rocketryforum.com/showthread.php?52251-Parachute-packing-question

I do it in step 1b of your directions.

Fruity Chute website has good info on packing their chutes. They wrap the lines around the chute. Some completley disagree with this method, but it is hard to argue with one of the best parachute manufacturers. I have done it both ways and not had a failure with either method.

No one can be faulted if you follow the directions for the chute. If you have a partner, have them help hold and squeeze. I know it helped me. I wish you success.
 
I certed L3 using a nosecone that separated from the rest and pulled a deployment bag to deploy the main. I did it to reduce the weight of the main rocket by about 8 lbs so I didn't need so large a chute. When I deployed at 600', the nosecone landed about 20' from the rest of the rocket. No need for a separate tracker on that setup.

Exactly unless there is tall vegetation nearby that can potentially swallow rocket parts. A screamer might go a long way here but if there is the prospect that the
NC and rocket body might be at a distance from each other, some sort of tracking might be insurance here. Kurt
 
Exactly unless there is tall vegetation nearby that can potentially swallow rocket parts. A screamer might go a long way here but if there is the prospect that the
NC and rocket body might be at a distance from each other, some sort of tracking might be insurance here. Kurt

Yep. I have sonic beacons on mine that practically deafen me. If the surrounding fields are all corn stubble, I don't put them in. We do have some fields with soy where a rocket can get swallowed up, so I would put them in then. I matched the descent rates for both separate vehicles, so even in the 11 mph winds we had, they stayed practically on top of each other.
 
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