I have two choices for my 29mm MD motor

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rockets

rockets

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OK, as you may have seen my thread about my 29mm MD rocket. I have ordered all of the parts needed, except for the motor, which I will pick up at a local rocket club launch.
These are my two choices:
Aero-Tech H195NT DMS motor, $29.99. 1.14 second burn time, 236Ns (total impulse)
My other possible choice
Aero-Tech H135W DMS Motor, $29.99. 2 second burn time, 225.84 Ns (total impulse)
_______
Yes, I know, you are probably asking yourself, Why isn't he doing a reload motor, or a CTI Motor?
The reason for that: If I lose this rocket, I don't want to lose a (probably $80+ casing) If I lose this, I will lose a $30 altimeter, which I still won't be happy about, but it isn't as bad as losing even more money. I hope you all understand my concerns.
__
two more questions. First, PLEASE feel free to give your feedback on what you think would be a good name for this rocket. I want it to be something FAST, since RockSim says it will go about mach 2.08 and 8,500' or possibly more altitude on that.
And second, what color rocket do you think will be most visible in a cornfield (before the corn gets really high, so in the spring???)

Thanks,
 
rockets said:
OK, as you may have seen my thread about my 29mm MD rocket. I have ordered all of the parts needed, except for the motor, which I will pick up at a local rocket club launch.
These are my two choices:
Aero-Tech H195NT DMS motor, $29.99. 1.14 second burn time, 236Ns (total impulse)
My other possible choice
Aero-Tech H135W DMS Motor, $29.99. 2 second burn time, 225.84 Ns (total impulse)
_______
Yes, I know, you are probably asking yourself, Why isn't he doing a reload motor, or a CTI Motor?
The reason for that: If I lose this rocket, I don't want to lose a (probably $80+ casing) If I lose this, I will lose a $30 altimeter, which I still won't be happy about, but it isn't as bad as losing even more money. I hope you all understand my concerns.
__
two more questions. First, PLEASE feel free to give your feedback on what you think would be a good name for this rocket. I want it to be something FAST, since RockSim says it will go about mach 2.08 and 8,500' or possibly more altitude on that.
And second, what color rocket do you think will be most visible in a cornfield (before the corn gets really high, so in the spring???)

Thanks,
Click to expand...
Will it be stable at that high speed? I would probably choose the h195nt motor. Nice flame, and faster flight.
 
Either would work. It depends on what you want? First flight I might go with the H135 to make sure all is well. Heck, go with something a bit smaller. If you have not done these sort of rockets before they tend to teleport with even moderate thrust motors.
 
rockets said:
According to RockSim, it should be fine.
Thanks,
Click to expand...

Make sure you check the CP with both the Barrowman and Rocksim methods of calculation (it's settable in the general settings tab of the design). The Rocksim method tends to be a little generous and push the CP further back than Barrowman. I would stick with the most pessimistic of them.

It's not a trivial difference either on some rockets. For example, my L3 rocket has a difference of 6.5in (almost 3/4 caliber) between the 2 methods.
 

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