2 stage rocket... without the booster stage

I've got a project in mind for a 2-stage rocket, but without the booster stage. What I mean is, the booster motor would stick out the back of the motor mount by about half the length of the motor, and the 2nd stage motor would kick the booster out, which would fall to the ground, but there would be no reusable booster stage tube & finset that I would have to go find.

Would the upper stage motor char the inside of the motor tube too much?

I did find this thread regarding a motor inside a tube
https://www.rocketryforum.com/showthread.php?63316-Simple-finless-rocket-in-flight

Seems like in the configuration I am intending, the thrust would not be reduced significantly? Has this been done?

I guess what I'm after is called a "rack rocket." Anyone have experience with these? Are there any kits or build-logs I can use as a go-by? what is the best material to use for the rack, that can withstand the heat of the motors? Could wooden dowels simply be painted with high temperature paint (like what you'd use on a barbecue grill?)

It sounds like you might be talking similar to the idea of CHAD (cheap and dirty) staging. A search on this website will find more information.

Your upper stage rocket would severely damage the inside of the rocket. About 40 years ago, I launched an Estes Mini-Brute Midget in two stage configuration. The upper stage ignited and I didn't see the booster separate. When I recovered it, I noticed the booster motor ejected but the booster remained attached. The booster body tube (the booster was minimum diameter - body tube was also the motor mount tube) was mostly burned away. All that remained of the body tube was the top part above the bottom of the upper stage motor and a little under each fin.

Your idea is sound. It's called CHAD (Cheap and Dirty Staging). Have the upper stage motor extend slightly out of the upper stage motor mount and enlarge the fins so it will be stable with the booster motor attached.

Here's the link to a CHAD article on the Apogee site:

https://www.apogeerockets.com/education/downloads/Newsletter339.pdf

Thanks for the links and info.

Looking into these "rack rocket" designs, the problem seems to be charring, requiring re-application of foil covering the rack after every couple of flights.

I can cut G10 FR4 fiberglass easily on my CNC router. Think this would stand a better chance of reusability, without having to cover it with anything? It is a natural flame retardant (that's what the "FR" stand for) but the max operating temperature is only about 300 F.

This is as close as I have come to what you are describing.









Approximately half the length of the booster motor fits inside the sustainer stage’s airframe.

The booster-pod doesn’t really have a body tube and the three tiny fins probably don’t contribute anything to the stability of the complete rocket.

This is actually the forth iteration of this rocket. The first one was built so flimsy that it collapsed during flight. The second was so heavy that the C6-O didn’t loft it with enough velocity as to make it stable; it crashed and burned.

The third version, built around 24mm motors, flew perfectly and then separated at deployment with the main body falling into tall corn never to be seen again and the nosecone and its parachute going Dorothy Gale.

The forth and current rocket has flown successfully several times.