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The Mid Power Clustering Question

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rabidsheeep

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Well this has been a topic in chat that pops up every now and then so i guess ill just ask it here.

Can you cluster 2 G motors without a level one cert? Some people said that you could for the g64, others said no, and im so confused.

I know you can cluster any 2 f motors (thats what i got from the info at thrustcurve) but the limits with g's is confusing me a bit...
 

JoJo

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if so why dont you just wait until they allow jr HPR cert. other than that im not sure
 

AlexM

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This is from EMRR:
1.) High Power Rocketry. High power rockets are defined as having: a single motor with more than 160 Newton-seconds total impulse or an installed impulse of 320 Newton-seconds and no more than 40,960 Newton-seconds, and an average thrust in excess of 80 Newtons. (H through N range);
2.)Depending on the context, may also refer to the title of the TRA's journal
 

rocketsonly

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Here are the rules from NAR:

"Size. My model rocket will not weigh more than 1,500 grams (53 ounces) at liftoff and will not contain more than 125 grams (4.4 ounces) of propellant or 320 N-sec (71.9 pound-seconds) of total impulse . If my model rocket weighs more than one pound (453 grams) at liftoff or has more than four ounces (113 grams) of propellant, I will check and comply with Federal Aviation Administration regulations before flying."
 

marvSRG

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With out a cert you can cluster up to a full H motor in power (320NS), and when certified you can only cluster in that HPR range.
 

DJ Delorie

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Does this mean I can put three F's in my 3x24mm Solar Sailer? :)
 

Stymye

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with the proper setting and the* necessary waivers *you can basically fly anything...it's called amature rocketry

obviously,at a nar or tripoly sanctioned event you have to operate under the rules everyone else does

so what this site says, or that site says, is true under those particular circumstances.
 

wwattles

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I'm personally fond of the idea that if you purchase your own island somewhere out in the middle of the ocean, clear it and level it, you can launch whatever you durn well please!

So who's up for it? Wanna go buy a TRF island? Guess I gotta start collecting recyclable cans and mowing lawns or somethin'...

WW
 

DynaSoar

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Originally posted by rabidsheeep
Well this has been a topic in chat that pops up every now and then so i guess ill just ask it here.

Can you cluster 2 G motors without a level one cert? Some people said that you could for the g64, others said no, and im so confused.

I know you can cluster any 2 f motors (thats what i got from the info at thrustcurve) but the limits with g's is confusing me a bit...
The MPR/HPR limit is 160 n/s for one motor, 320 n/s for multiple motors. Two G64 or G80 is 240 n/s. That's allowed without L1. You could cluster 3 G35s for a total of 315 n/s without L1.
 

Rocketjunkie

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Originally posted by DJ Delorie
Does this mean I can put three F's in my 3x24mm Solar Sailer? :)
Yes you can. Check the propellant weight, it might be enough to require a waiver (Black Jack likely, other propellants probably not).
If the propellant weight is over 125 grams, you'll need a waiver and it won't be a model rocket anymore.
 

DJ Delorie

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Ok, three F21W-8's is 90g total propellent, 165 N total, 66 Ns average.

Sweet.
 
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