Absurd Numbers In Open Rocket

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littlemisterbig

littlemisterbig

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Hi All,

I've been messing around in OR and a lot of the time, when designing a rocket, the sims give me insane acceleration number (around 38,000 F/S^2) and very low altitude numbers (2-3k') this gets very aggravating and no matter how much nose weight I add, the number still don't become realistic. The numbers given in the previous sentence are from the sims fro a 38mm minimum diameter I designed while being bored in Biology, those numbers are it on a Loki K-1127. Is anyone else having these issues? If so, do you know how to fix it?

Thanks
 
Ok, well that's on my other computer so I'll throw something together quickly, as this is a problem with all my designs not just this one.
 
I haven't had those problems, could it be some erroneous setting somewhere under preferences?

Nate
 
Is your recovery set to fire too low?

I tend to work with all set to apogee, regardless of how it will fly in reality.
 
something is up with the units. to get 38,000 ft/s^2 (1181g's) K-1127 is 1428N max thrust. so you would have to be about 4.3oz with motor...
 
littlemisterbig said:
Hi All,

I've been messing around in OR and a lot of the time, when designing a rocket, the sims give me insane acceleration number (around 38,000 F/S^2) and very low altitude numbers (2-3k') this gets very aggravating and no matter how much nose weight I add, the number still don't become realistic. The numbers given in the previous sentence are from the sims fro a 38mm minimum diameter I designed while being bored in Biology, those numbers are it on a Loki K-1127. Is anyone else having these issues? If so, do you know how to fix it?

Thanks
Click to expand...

You are most likely going unstable due to the high velocity and resulting CP shift, resulting in the very low altitude and weird acceleration numbers I would guess to be from the simulation of the rocket spinning unstably while still under thrust. Make the fins larger or add nose-weight and the weirdness should go away.
 

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