byoungblood
Well-Known Member
- Joined
- Jul 19, 2014
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I've built an upscale (BT-70/60) of an Estes Echostar that has come out to about 10.7 oz with motor, sans final paint.
According to Estes motor charts, it is a tad too heavy for a D12-5, but should be fine on a D12-3, understandable given the weight of the rocket.
I plug it into ThrustCurve, and the smallest engine it recommends is a E20. I'll have to run RockSim again to make sure I have the final assembly weight correct, but it was showing about 40-41 ft/s off of my 4' rod with a D12.
So given the Estes chart and Rocksim I should be OK with a D12-3, but ThrustCurve says I need more motor. Should the Estes charts really be relied on as more than a general guideline, or are they a bit too optimistic?
According to Estes motor charts, it is a tad too heavy for a D12-5, but should be fine on a D12-3, understandable given the weight of the rocket.
I plug it into ThrustCurve, and the smallest engine it recommends is a E20. I'll have to run RockSim again to make sure I have the final assembly weight correct, but it was showing about 40-41 ft/s off of my 4' rod with a D12.
So given the Estes chart and Rocksim I should be OK with a D12-3, but ThrustCurve says I need more motor. Should the Estes charts really be relied on as more than a general guideline, or are they a bit too optimistic?