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Which do you like better?

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In your experience, which is worse?

  • Motor ejection 1 second early

  • Motor ejection 1 second late


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jeff_j_black

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So you've calculated things carefully. You know your stuff. But the conditions aren't what you expected or there was some other variance. From your experience with motor ejection, which is worse?
Ejection 1 second early
Ejection 1 second late
 

rharshberger

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So you've calculated things carefully. You know your stuff. But the conditions aren't what you expected or there was some other variance. From your experience with motor ejection, which is worse?
Ejection 1 second early
Ejection 1 second late
Either is within the acceptable range. For altitude reasons I prefer to be a second late, and the rocket is no longer climbing.
 

Rocketjunkie

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Either works. If your recovery system can't handle 2-3 seconds either side of apogee, you have a problem. On windy days, go to the short side.
 

Rex R

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at 1 sec early the rocket(in theory) is at 32 fps and slowing(apogee within 16'), at that speed it takes about a second for the chute to unfold(it also needs about 5 fps to open) so, you're not losing much altitude.
Rex
 

bobkrech

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If you use motor ejection, your rocket better be able to handle +/- 5 seconds off apogee, or some day you will have a problem.....
 

jahall4

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So you've calculated things carefully. You know your stuff. But the conditions aren't what you expected or there was some other variance. From your experience with motor ejection, which is worse?
Ejection 1 second early
Ejection 1 second late
I try not to "experience" a motor ejection at all :wink:, but when I'm forced to decide (motor ejection is the primary) I usually assume the rocket will NOT go as high and choose the lower delay. It is easier to get the laundry out of the tube and slow the rocket down with it traveling upwards.
 
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