Help with engine choices for Estes MIRV

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BABAR

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Okay, so building this, read previous posts. Sounds underpowered for a C a bit like some other oversized Estes rockets relative to their 18mm motor mounts.

https://www.amazon.com/dp/B004L10OLE/?tag=skimlinks_replacement-20

When I built my ExoSkell I put in a 24mm mount and flew great. The MIRV doesn't lend itself to that solution. Was thinking about an 18mm D. I am thinking of trying Klima motors (I need a zero delay, and I don't see one from aerotech anyway.). Prices look reasonable, especially since I can use Estes starters, of which I have a bunch from my blast off packs of 24 (which Estes nicely packs with 36 igniters, at least all the ones I have bought.)

I am looking at the Klima D9-0

https://www.sierrafoxhobbies.com/en/238-motori-d

I would think that would get me off the pad fast and wouldn't burn as long as the D3-0, I don't want this to go too high. Will that be too much power? I am papering the fins and possibly the foam surfaces too, so it might be a bit heavy. Putting a bit of aluminum over the booster foam section in place of the little foil strips that comes with it.

Going to try and paint fins before attachment, leaving contact points bare.

Anyway, ideas regarding motors for this birds appreciated. I am kind of curious to try the Klima 18s just to see how well they work.

Thanks,

Tom
 
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rharshberger

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The MIRV is not a altitude type rocket, as its designed to fly apart as soon as it stages into smaller unstable pieces. More altitude would just be asking to lose pieces, most MIRV launches I have seen probably didnt get to 150' max altitude and staged at about 50-75'.
 

BABAR

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The MIRV is not a altitude type rocket, as its designed to fly apart as soon as it stages into smaller unstable pieces. More altitude would just be asking to lose pieces, most MIRV launches I have seen probably didnt get to 150' max altitude and staged at about 50-75'.
Did they do okay on a C6-0?
That's my main concern.
 

rharshberger

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Did they do okay on a C6-0?
That's my main concern.
We have at least one flown at every club launch and they do fine on the recommended motors, however the "projected max altitude" from the face card is grossly over estimated IMO, the rocket is a definite low altitude crowd pleaser for first timers, and even after seeing them flown at every launch, I think its a neat rocket. They do fine IMO on the C6-0 booster motor.
 

rstaff3

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I got one while they were on sale at Estes. Mine flew once on a C6-0 to three A10-3s, as recommended. It boosted cross-wind vs into or with it. The altitude was about what Rich reported. The three boosters were stable in that the didn't skywrite. However, all three went off in different directions. All 4 pieces ended up in the soybeans. The sustainers were found but I never got the booster back.

And, yes, it was a hoot!
 

BABAR

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rstaff3

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Another thing to consider when upping the booster motor, the three sustainers are only held in place by the plastic duct thing on their butt end. Too much speed would likely shear them apart.
 
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