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Marlin523

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Which situation do you think is more likely to cause this? Deployment before apogee or after apogee?
 

stantonjtroy

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One is as likely as another. It has less to do with where the rocket is on the balistic trajectory than velocity at the time of deployment. Haulin butt up or hualin butt down is still haulin butt.
 

ScrapDaddy

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After, as the rocket would be picking up speed. If it deployed before it would be rapidly drcellerating
 

new2hpr

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Ditto Troy's answer. Same either way. I've had an early deploy at about 120mph. Talk about rapidly decelerating! Everything held, except 4 zippers of assorted sizes and directions :mad:

Data from the MAWD showed a sudden flat top to the curve!

-Ken
 

slogfilet

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After, as the rocket would be picking up speed. If it deployed before it would be rapidly drcellerating
While this is true, it is not acceleration that is the problem, it's velocity. For example, hitting a an object with your car at 50mph will yield the same effect whether you were riding the breaks or the gas at the time.
 

Marlin523

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Well said. For midpower rockets what range of velocity do you consider to be optimal. It isn't always easy to find a thrust/delay combination that deploys at apogee.
 

stantonjtroy

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For most any rocket, 19 -28 feet per second isn't bad. Faster and you risk damage, slower and you take a walk. Peak altitude is a factor to consider. There are always exceptions. All this asumes single stage (apogee) deployment.
 

stantonjtroy

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After, as the rocket would be picking up speed. If it deployed before it would be rapidly drcellerating
Rember that along a balistic trajectory velocity increases, decreases and increases at a comperable rate. Variances come from acceleration under thrust on the ascent and terminal velocity on the down side. Middle third follows the profile given here. (more or less)
 

Pantherjon

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Could also be too short of shock cord causing the nosecone to 'rebound' from the ejection charge..
 
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