Lil' Nuke stability

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dragonshiprider

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I have a LOC Lil' Nuke that I am gonna be flyin' for the first time at the next Battlepark launch.This rocket is balanced at about 2 1/4 calibers positive with a loaded G-motor.Will this be o.k.? Does it always take this much mega weight to get this thing stable?It took a bunch of epoxy and lead shot.
 

teflonrocketry1

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According to the RockSim file at EMRR which was made by Steve Naquin, from "Measurements & Weight Taken From Actual Assembled Kit (Actual Built Weight = 14.4oz)" you shouldn't need to add any nose weight to achieve a stable flight on a G motor visit:
https://www.rocketreviews.com/rocksim/LocLiLNuke_5.rkt
you can open this file with the demo version of RockSim available at: https://www.apogeerockets.com/rocksim_demo.asp

The 1.63 caliber static margin predicted by the Barrowman equations or the 2.10 static margin using RockSim equations should make for a stable flight.

Bruce S. Levison, NAR #69055
 

dragonshiprider

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According to EMRRs CP list the CP of this rocket is 7.9 inches from the rear and about 22 inches from the nose. The rocket now balances at about 12 inches from the rear.It took over a pound to get it there.I don't know how anyone else built theirs but with no weight added mine balanced about four-five inches from the rear with a G motor installed.This is well behind the CP.
 

Daedalus

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Mine is built dead stock (first mid power model). It flies dead straight and is perfectly stable on F20s. Can't remember the heaviest motor it has flown on but I know it has had the 29/40-120 case in it and a cone Rowes retainer on it - again no stability problems.

All that nose weight is way too much
 

dragonshiprider

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Well then does this throw all theoriews about CP and CG out the door? We would be talking about a rocket that flies well with it's CG behind it's CP.
 

jrogers

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The Lil Nuke was my very first rocket, built stock, first flight was a G80, straight and fast.
 
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