Breaking the Law?

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Well-Known Member
Jan 13, 2004
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Is it a no no to stage to engines of different diameters together? I was thinking starting stage 1 with a D-12-0 and ending stage 2 with a C-6-7. I know it will make taping the motors difficult, but other than that, any other problems?

This practice is perfectly legal and engouraged!

Take a look at the Estes Comanche 3. It stages (in order) D12-0 / C6-0 / C6-7

It actually works quite well because the nozzle or exhaust end of the C engine nests quite nicely inside the top of the D booster, making stage ignition even more likely.

Have Fun!
The FlisKits Nomad does the same thing. 24mm in the 1st stage and 18mm motors in the 2nd and 3rd stages.

I also do it with our Pheord X150 saucer (18mm) with one of mini (13mm) saucers from our Triple Threat kit as an upper stage.

Absolutely not! Look at the Estes Comanche 3 when it fully loaded: the first stage is powered by D12-0, The second stage is powered by a C6-0 and the sustainere is powered by a C6-7! Three stages!!! 24mm-18mm-18mm

The FlisKits Nomad uses the same setup, albeit with a neater design :D

The old Estes Magnum also staged a 24mm to 18mm.

You really don't have to tape the 24mm to the 18mm because the nozzle of the 18mm fits into the top of 24mm booster
Originally posted by sandman
Is there an echo in here???

sandman there an echo in here???... there an echo............


Originally posted by HiflyinPRguy
The FlisKits Nomad uses the same setup, albeit with a neater design :D

why, *thank you*! :)

Not only is it OK, the 18mm motors fit inside the 24mm booster casing.
I fly a 2 stage UFO by simply sitting C6-0 inside the D12-0 of the lower stage. A real attention getter at shows.

Sorry this is the only pic I have of the model scanned, I have some pretty good flight photos i've never taken the time to scan and clean up.