Great idea or really stupid?

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Sooner Boomer

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My buddy Braz was the local King of Klusters. He passed away in 2011. One of his projects of note was a big cluster (and I can't remember how many) rocket using 18mm engines. Flew wonderfully. But that wasn't enough, so he CHAD staged it. A friend said he made it rain engines when it staged! We've got a memorial launch for him in May. I've got a clustered Fat Boy to fly then. I thought I'd CHAD stage it in his honor, but got to thinking I'd try something a bit different - only CHAD staging *half* of the engines, but igniting all (bottom) engines at the same time. That is, the rocket has 8 engines. I CHAD stage half, but ignite the four boosters and the four non-staged engines together. This gives eight engines on liftoff, that would stage four of them in flight. I'd have to find a way to deal with the ejection charges of the non-staged engines, but that should not be hard. Why do this? Why not/ Have you heard of anyone doing it? Great idea, or really stupid (I could sell tickets for either).
 

Sooner Boomer

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CHeap And Dirty - just taping a booster engine under the sustainer - no body tube or mount.
 

Sandy H.

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It seems that CHAD staging a short clustered rocket might require a ton of noseweight. Also, would the 4 CHAD motors be behind the flame from the 4 other motors lit on the ground? That could be troublesome, but maybe I'm misunderstanding the arrangement.

Sandy.
 

Sooner Boomer

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It's a Fat Boy - it has a LOT of nose weight! Yeah, they might get toasted a bit, but I don't think it will be a problem. Might just CHAD stage all of them. I have a while to figure it out.
 

MClark

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I have chad staged clusters mostly with D motors but also with smaller.
Best results were having 3 or 4 motors in each stage, no motors trapped inside as you get with 7, 12 etc.
It seems the inside motors try to stage before the outside motors with bad results.
 

tab28682

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CHeap And Dirty - just taping a booster engine under the sustainer - no body tube or mount.
Mostly used with taped on booster motors, but the term does get tossed around at launches referring to other simple, cheap, kludged up stuff
 

BABAR

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Heck, if you are gonna CHAD stage anyway, you are already dropping 4 motors from the sky. Use zero delays in the non staged booster motors, seal the tubes and eject them with the CHAD motors. If a field allows 4 falling 18 mm casings, 4 more not a big deal.

May want to paint the casings fluorescent pink or orange to make them easier to find afterwards, have prizes for the kids that return them. Do NOT announce that BEFORE the field is "safed" for recovery by the RSO or LCO, or you will have kids champing at the bit to get on the field searching. So make that the last launch from that pad or section.
 

jimzcatz

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not to be "that guy" but is dropping anything uncontrolled from a rocket on purpose really allowed? It would seem against safety codes to me. What am I missing?
 

dhbarr

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Although dropping a spent motor is a DQ in NAR competition, I'm not aware of anything in the Model Rocket Safety Code that forbids it. I know some clubs have explicit rules about this, and would imagine most places you'd get a hairy eyeball if CHADding 29's.
 

Steve Shannon

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My buddy Braz was the local King of Klusters. He passed away in 2011. One of his projects of note was a big cluster (and I can't remember how many) rocket using 18mm engines. Flew wonderfully. But that wasn't enough, so he CHAD staged it. A friend said he made it rain engines when it staged! We've got a memorial launch for him in May. I've got a clustered Fat Boy to fly then. I thought I'd CHAD stage it in his honor, but got to thinking I'd try something a bit different - only CHAD staging *half* of the engines, but igniting all (bottom) engines at the same time. That is, the rocket has 8 engines. I CHAD stage half, but ignite the four boosters and the four non-staged engines together. This gives eight engines on liftoff, that would stage four of them in flight. I'd have to find a way to deal with the ejection charges of the non-staged engines, but that should not be hard. Why do this? Why not/ Have you heard of anyone doing it? Great idea, or really stupid (I could sell tickets for either).
Just use plugged motors for those which don’t stage.
 

Steve Shannon

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Although dropping a spent motor is a DQ in NAR competition, I'm not aware of anything in the Model Rocket Safety Code that forbids it. I know some clubs have explicit rules about this, and would imagine most places you'd get a hairy eyeball if CHADding 29's.
I don’t believe it’s permitted by high power safety codes. For anything else my concern would be the landowner.
 

heada

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At a minimum you should tell the RSO/LCO and have it announced that there will be falling spent motor casings. The shot-gun ejection on some of the 24mm Estes motors can kick it out at fairly high energy and at somewhat random angles. I've seen 13mm cases get ejected at good speed as well.
 

BABAR

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I don’t believe it’s permitted by high power safety codes. For anything else my concern would be the landowner.
Yeah, I think think CHAD staging a high power motor comes close to CATCHING a High Power rocket as potential Darwin Award winning entries.

Not high power, but I remember der MicroMeister (man I miss him) talking about using motor eject on G motor rockets at NAR events. Yikes!
 

Sooner Boomer

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Heck, if you are gonna CHAD stage anyway, you are already dropping 4 motors from the sky. Use zero delays in the non staged booster motors, seal the tubes and eject them with the CHAD motors. If a field allows 4 falling 18 mm casings, 4 more not a big deal.

May want to paint the casings fluorescent pink or orange to make them easier to find afterwards, have prizes for the kids that return them. Do NOT announce that BEFORE the field is "safed" for recovery by the RSO or LCO, or you will have kids champing at the bit to get on the field searching. So make that the last launch from that pad or section.
The problem with plugging the "tubes" is that I'll want to fly it again on all motors as a single stage. I guess if using the ejection charge from half is good enough for staged flight, it would be good for single, too. I'm thinking about not doing the staging bit. That's a whole buncha money for all those C motors. And a buncha more to stage them.
 

cwbullet

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We have a flier that does this. We allow it on our field for low power and BP only.
 
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