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Beginner to Two Stage Rockets

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AidanDelli

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Okay so I bought a bunch of pre-fabricated Estes parts that I'm planning on turning into a two stage rocket. I understand how to build one and what they are etc. but I was wondering how to add a recovery device to the booster stage. In the first one, a black powder charge will deploy the parachute but how would I add a feature like this in a booster stage without an ejection charge? I was planning on probably using a streamer or parachute for the booster just so I can retrieve it but was just confusing myself on how I would actually attempt it for my first time. Any help is greatly appreciated!
 

dhbarr

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Size of the booster matters. Below a certain point, most folks just make sure it can tumble safely.
 

K'Tesh

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I would suggest checking out a few of Estes instructions for 2 stage rockets. Then see if you really need a recovery device.
 

BDB

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If the booster stage is basically the length of the motor plus a coupler, like all Estes 2-stage rockets that I know, tumble recovery should be fine.
 

Wayco

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My first rocket was the Estes Mongoose, a small 2 stage rocket that flew on 18mm motors. After a few flights, the booster, which is supposed to "tumble" recover, was damaged on impact. I moved the fin can to the middle of the tube, and it fluttered down with no damage. Larger models, like the Apogee Rip Roar, also use tumble recovery, but usually sustain damage on landing due to the heavier components. I have tried several methods to add a chute or streamer, but they are always damaged by the separation charge.
I would suggest you build a couple of 2 stage kits before you try to tackle adding a chute or streamer to the booster, it will give you a better perspective on recovery.
 

BABAR

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For a "typical" two stage rocket, you will have a very short booster, and little or no gap. Your booster will have pretty big fins relative to the sustainer (required to get the stability margin right, with at least two engines in back--- booster and sustainer--- your CG is pretty far back compared to a single stage.)

With this short booster configuration, at separation your booster section is inherently unstable (a GOOD thing in this situation) and will tumble back to the ground, hopefully with little or no damage. May want to make your fins a bit thicker and fillets a bit stronger than you otherwise might for a single stage. But no specific streamer or chute is required for low power two stage. Definitely needed for High Power and probably advisable for mid power.

If you go for significantly long gap staging
see http://www.rocketryforum.com/showth...ged-2-successful-flights!&highlight=gap+stage
your booster will still be stable post separation if you do NOT have some sort of recovery device , and it will lawn dart to the ground. This is generally considered non-optimal.

Lots of options to add a recovery device, as seen on the post above, auxilliary pods with engines with non-0 delays will deploy a chute or streamer AFTER separation is initiated by the 0-delay booster motor.

another option is horizontal spin recovery of the booster

http://www.rocketryforum.com/showth...aging-see-last-Post&highlight=horizontal+spin

If you do choose to gap stage (booster/sustainer motors not taped or at least directly butted booster front to sustainer tail/nozzle), you really should have some vent holes or other mechanism to vent the air in the space between motors. Otherwise the air pressure may separate the stages BEFORE the hot gas plume from the booster reaches the nozzle of the sustainer to illuminate and ignite the sustainer. MUST----- NOT-----SAY----PARTICLES............:bangpan:

Good luck, straight trails, and look forward to pics and flight reports.

Tom
 
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