How tall should my launch tower be ?

I launch mainly 3" rockets upto about an 'M' but want to build an adjustable launch tower to take bigger and smaller diameter rockets.
Is there a formula to calculate the minimum height ?

You want it tall enough to give you the minimum safe launch velocity and that really depends on weight of rocket & the motor you are using.

About 20lbs with an 'M'

Interceptor said:

... Is there a formula to calculate the minimum height ?

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I think this is what you want:

= ( Desired.Velocity.mps ^ 2 ) * ( Rocket.Mass.g / Avg.Motor.Initial.Thrust.N ) * 0.5 + gravity



You may want to check the formula and assumptions independently. YMMV.

Greg

Per illustration a 21" tower is all that is required. While it is true I want to hear the explanation to the RSO.
Although not needed for reaching minimum velocity people "like to see" a tower at least as long as the rocket.

M

MClark said:

Per illustration a 21" tower is all that is required. While it is true I want to hear the explanation to the RSO.
Although not needed for reaching minimum velocity people "like to see" a tower at least as long as the rocket.

Click to expand...

In other words, there is a distinction between the "physical" length of the tower and the "effective" length of the tower. The latter can be described as the minimum length a rocket can travel, while still being guided effectively by the tower. In the example above, a rocket can be launched with a tower that is effective for at least 21" - physically the tower will be much taller to achieve this (details vary, depending on fit of the rocket, stiffness of the components, etc).

Reinhard

GregGleason said:

I think this is what you want:

= ( Desired.Velocity.mps ^ 2 ) * ( Rocket.Mass.g / Avg.Motor.Initial.Thrust.N ) * 0.5 + gravity

View attachment 270890

You may want to check the formula and assumptions independently. YMMV.

Greg

Click to expand...

Could you by any chance post that file or send me a copy of it? Thanks!