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How can I get a slow lift-off?
#1
I happened upon this by accident - I was launching a few rockets for family and friends and one of my Fat Boys took off in a visibly deliberate and slow lift-off, much to the delight of all, including me.

I have tried to repeat that again to no avail.  My question is:  Are there any rockets out there that are designed for a slower than normal lift-off?  Or, what modifications could I do to try and create a slower, more deliberate lift-off?

Thanks!
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#2
Larger, fatter, heavier rockets is one way, larger and draggier (although drag doesn't come into play until after liftoff...) and the other half of the equation is motor selection... course the smallest, lowest peak thrust motor the rocket can SAFELY fly on... this will reduce the "oomf" off the pad and give a slower liftoff...

Notice I said "safely"... you have to make sure that the motor you choose can get the rocket up to about 30 mph or more before it leaves the launch rod, so the fins can stabilize it. This might require use of a longer launch rod so the extra length gives additional time for extra acceleration...

That's where a good rocket simulation program really helps... and you need to make sure the selected motor and time delay are matched so the rocket gets sufficient altitude to reliably deploy a chute or streamer before it hits the ground, and as close to apogee as possible rather than a late, high speed deployment that tends to tear things up...

Later! OL J R
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#3
Go to thrustcurve.org and create a sim for your rocket. The sim will show you the safe motors. Find the one with the lowest thrust.
John S.
NAR #96911
TRA #15253
MDRA
Level 1, 2014-Mar-15 -- Aerotech Sumo, H133BS
Level 2, 2014-Jun-21 -- Giant Leap Vertical Assault, J240RL
Level 3, 2016-03-12 -- MAC Performance Radial Flyer, M1101WH, 13,028 feet
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#4
Appreciate the help. I thought I knew a bit about the motors, but your answers regarding MPH and thrust are making me realize that I do not. I will brush up on that as well as use the thrustcurve.org site.

Thanks!
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