Susan,
Over the decades, I have seen MANY Comanche 3 rockets fail to stage, resulting in a crash that destroys the upper stage . . . Frankly, I have seen more of them fail, than succeed.
I think this may be due to the "tape together" method used to temporarily join the rocket motors together. My theory is that the "burn-through" of the lower engine causes the pressure to rise to the point where the motor above it is separated BEFORE ignition can occur. I never like the "tape together" method for multi-staging.
Decades ago, another model rocket company, called Centuri, developed a system called "Pass-Port" staging, which was highly reliable. Basically, the system incorporated a "port" that allowed some of the pressure to escape and allow extra time for the upper engine to ignite.
https://oldrocketplans.com/pubs/Centuri/TIR-123.pdf
Being a BT-50 model, with BT-20 engine mounts, it is possible to modify the Comanche 3 for this type of staging method.
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