# 5:1 Thrust to weight ratio

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#### AfterBurners

##### Well-Known Member
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

#### rstaff3

##### Oddroc-eteer
And the chute, preferably.

#### markkoelsch

##### Well-Known Member
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

#### dhbarr

##### Amateur Professional
Don't add the weight of the igniter; everything else counts

#### AfterBurners

##### Well-Known Member
Thanks guys. Much appreciated

#### FredA

##### Well-Known Member
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.