Zero Delay Engines for Booster Deployment?

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Well-Known Member
Dec 29, 2003
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Can anyone give me an idea of the effectiveness of using B6-0 or C6-0 engines to deploy parallel stages? Essentially I want these engines to pop a nose cone off of a parallel stage to allow it to separate from the sustainer after/during motor burnout.

I've seen references to this technique but would like some hard facts and experiences if there are any out there. Thanks!

0 delay booster motors expell enough gas forward at burn through to pop just about any cone. I've used the technique on several models. In several cluster models I forgot to vent the booster tubes.. using booster motors friction fit, and externally taped I have yet to keep the motors in the tubes after burnout... the report is even louder the tighter I tried to tape them in:) If you are ejecting nosecones up to BT-60 size you should have no trouble at all.
Thanks Micromister--this pretty much confirms what I'd heard before.

Using a booster? I don't know enough to answer. I do know i've used one with a charge to deploy in a 2.56 before, worked fine.
Ok, then yes, im sure it could. On the rocket I did it with, the charge was moving ~1.5 pounds of payload, and a 36 inch nylon chute, and shock-cord, so unless your cone is glued on, youll be fine...)
usually on my BT-80 D12 powered models I use a BT-55 or BT-60 stuffer tube between the MMT and the Chute compartment. I've found a 12 to 14" chute compartment will handle up to a 48" nylon Hemi chute or two smaller chutes easily.
Hope this helps.
Using a B6-0 or C6-0 to blow the nose off a paralle stage booster: yes, I have done this with a couple of models. I haven't tried it with a BT-60 but I have done it with a fairly long BT-55 - four of them, to be precise, on my Thunderbird missile.

Using a D12-5 to blow the parachute out of a BT-80: yes, the Thunderbird's sustainer does it. But in a couple of models using BT-80, I've fitted a piston made from a BT-80 coupler and a balsa disk, partly to improve ejection reliability and partly to save on wadding. :D