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Nosecone Parachute

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Nite Builder

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I recently finished consructing a LOC Warlock and will be soon pumpin it up on an AT I435T. Both BT and nose have been glassed and it weighs a little bit more than it would if it wasn't glassed.(About a Lb. more) I will be using AT delays on the first few flights or until the avionics bay is completed so I'm keeping my fingers crossed that I don't get a bad Aerotech RDK+ delay( and yes, they are out there). With that in mind I feel it necessary to designate the nosecone with its own respective parachute so as to prevent too much damage to the rocket "should" it eject early. I strongly feel that should I exprience early ejection, at least the weight of the nosecone won't zipper the BT as badly considering that this is a very large nosecone. I have to admit, I have heard both good and bad reasons of why I should or shouldn't do this. I figured I would let the Forum "naw" on this one for a while. What do"you"think guys?
 
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Austin

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Nite...

On rockets with heavier nosecones, which covers about 75 percent of my fleet, I always use a seperate parachute for the nosecone itself. It comes from the school of hard knocks, having experienced a zipper from an early ejection. Since then, I have had many many flights with the Nosecone ejecting on its own 6-10' length of shock cord and parachute and have never had a zipper since...even in nose down situations( caused by delay testing ;) ) "Getting the Nosecone away from the model" has worked well and I highly recommend dual chutes for any nosecone that has more than half a pound of weight. Moreover, if you decide on dual deploy or just single deploy with a larger chute, you can use the NC parachute to pull the D-Bag out of your airframe for a insured parachute deployment; this will also get you used to using D-Bags...a deployment tool that is very useful in larger rockets.

Just speaking from experience,

Carl
 

Nite Builder

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Sometimes, just a little verification from a more experienced rocketeer goes a long way. I do appreciate it. I admit that I've heard more good reasons on why I should use 2 chutes than just one main chute, however the scuttlebutt around the club is that there is a special way to fold the 2 chutes together so as to provide a more reliable (less tangled, as it were) ejection. Are you familiar with this? Thanx again Carl.....
 

UhClem

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Although it is too late now, you should consider using anti-zipper construction in the future. See the Stu Barrett article in ROL's Info Central.

I recently used the noze cone on its own parachute trick for the first time at LDRS. The nose had three pounds of weight in it but I wasn't concerned about zippering (because of anti-zipper construction) but wanted to have the nose on its own parachute because my main parachute wasn't really rated to handle the additional weight.

I used a Rocketman R12 for the main and and R7 for the nose. I must have gotten really lucky in matching descent rates because they landed only a few hundred feet apart after drifting nearly two miles.

After a lot of thought I packed the parchutes:

Main:

1) R12 shroud lines tied to payload section.
2) deployment bag lanyard tied to nose cone.

Nose:

1) R7 shroud lines tied to the nose (of course).
2) deployment bag lanyard tied to apex of main parachute.

I then dropped the R7 into the nose first (did I mention that this all fits into the nose cone?) followed by the R12. During deployment, the nose will pull the deployment bag off of the R12. Once that happens, the lanyard to the R7 deployment bag pulls the R7 out of the nose and then the deployment bag pulls off of the R7.

Worked like a charm on both flights.

My only concern is that there is a slight chance that the deployment bag will pull off the R7 parachute before the parachute is out of the nose. I have an idea on how to fix this with some elastic and a little sewing.

David Schultz
 
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