5:1 Thrust to weight ratio

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AfterBurners

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I completely understand this method and calculations, but when they state the following:

"The average thrust of a motor should be at least five times the total weight of the fully loaded rocket"

Just needed some clarification on "Fully Loaded Rocket" as in with the motor loaded or without? I'm assuming with it loaded?

Then you make your calculations based on that weight
 

bobkrech

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Yes the pad weight is with the motor loaded.
 

markkoelsch

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I completely understand this method and calculations, but when they state the following:

"The average thrust of a motor should be at least five times the total weight of the fully loaded rocket"

Just needed some clarification on "Fully Loaded Rocket" as in with the motor loaded or without? I'm assuming with it loaded?

Then you make your calculations based on that weight
Fully loaded ready to fly.
 

dhbarr

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Don't add the weight of the igniter; everything else counts :)
 

FredA

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For a rough guide with a "normal" Bates grain motor, take the number part of the motor designation and divide by 25 and that should be equal to or larger than the pad weight in pounds.
 
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