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Launch day results a little confusing.

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Senior Space Cadet

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For reasons I can't really explain, I only took two photos and haven't run them through PaintShopPro yet.
All the rockets flew OK, but I'm not sure about chute deployment.
My first launch of the day was a small scratch built Honest John. Flew fine, but I followed the chute down and found the nose cone and chute, but no body. I never found the body, which is weird, so I have no way of knowing what the failure was.
I launched six rockets, in all, and it was apparent on a couple that the chute deployed properly, but was questionable on the others. When I retrieved the rockets I could find no reason why any the chutes wouldn't have opened perfectly. They were all out of the rocket, open, and no tangling whatsoever. Everything looked fine so, if they didn't deploy properly, I have no idea why.
It is possible they deployed but the chute was just too small, so they just came down fast. No matter what, it's a step in the right direction. Last launch day most of the chutes and lines were all tangled up.
One of the fins broke on my largest rocket, but I couldn't find it near the rocket. If it broke on landing, it should have been right next to the rocket. I don't know how it could have broken before that. Also weird.
 

rklapp

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Usually we find the BT and the NC/chute drifts off into another ZIP code.
 

samb

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The HoJo suffered a shock cord separation. Short cord, weak attachment point, or an over energetic ejection charge are some of the reasons. You’ll get all kinds of answers here for best shock cord length. I use 2X the airframe length.
Did you use plastic chutes ? Cold plastic keeps it's shape and resists unfurling. I always unfurl and pack my chutes as part of pre-flight at the field. I dust with baby powder and work the plastic while packing. No clue where the fin went. Hope this helps.
 

Senior Space Cadet

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The HoJo suffered a shock cord separation. Short cord, weak attachment point, or an over energetic ejection charge are some of the reasons. You’ll get all kinds of answers here for best shock cord length. I use 2X the airframe length.
Did you use plastic chutes ? Cold plastic keeps it's shape and resists unfurling. I always unfurl and pack my chutes as part of pre-flight at the field. I dust with baby powder and work the plastic while packing. No clue where the fin went. Hope this helps.
It was chilly, but not really cold. Probably around 40 degrees. Hard to say if cold was a factor. Yes, they were nylon chutes by Apogee.
I use a section of bungee chord attached to the nosecone to absorb shock, so I shouldn't get any breakage any more. It was the smallest body tube I launched that day, so ejection would have been more forceful.
 

samb

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It was chilly, but not really cold. Probably around 40 degrees. Hard to say if cold was a factor. Yes, they were nylon chutes by Apogee.
I use a section of bungee chord attached to the nosecone to absorb shock, so I shouldn't get any breakage any more. It was the smallest body tube I launched that day, so ejection would have been more forceful.
Ok, nylon is less susceptible to cold so my answer doesn't apply, although you may try a powder dusting next time to see if that has a positive affect. I'm at a loss explaining why you are having so much trouble with shock cords. 1/8 and 1/4 inch elastic anchored with a good old Estes tea bag has served me well for years. I've never tried paracord but it seems to me that it would take up too much space in a low power model rocket.
 
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Senior Space Cadet

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Ok, nylon is less susceptible to cold so my answer doesn't apply, although you may try a powder dusting next time to see if that has a positive affect. I'm at a loss explaining why you are having so much trouble with shock cords. 1/8 and 1/4 inch elastic anchored with a good old Estes tea bag has served me well for years. I've never tried paracord but it seems to me that it would take up too much space in a low power model rocket.
I'm not having a lot of trouble with the shock chord breaking or coming loose. The other five rockets I launched stayed together and the bungee chord was still attached to the nosecone and the parachute was still attached to the bungee chord. But I either, somehow, neglected to attach the Kevlar chord to it, or it, or the swivel clip broke, or I didn't tie a very secure knot. The Kevlar chord was tied around the motor mount, so it was really secure.
 

rklapp

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The only time Kevlar failed me was when I used dog barf in the Odyssey. I think the DB clogged in the tube and the charge busted the cord. The rocket fluttered down with minimal damage but the NC/chute drifted away. This was the 2nd NC I lost (first was to a tree). Although I have a replacement, decided to use a different scifi NC for good luck.

 
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