Nike Achilles 2-stage model rocket

thingiverse

There was no "Achilles" in the actual Nike-(greek hero) series the army fiddled with back in the day, but I designed a rocket inspired by them and imagined what could have been.I primarily designed this rocket to experiment with a gap between the booster and sustainer motors. Most Estes type designs put the motors right next to each other but by all accounts I could find, a gap up to 10" produces reliable ignition of the sustainer. This rocket is only about 5".In that gap I created a partition so that the booster could have it's own recovery system. I original had a 12" chute in there, but the deployment speed is way too fast so it will have to rely on a streamer. It doesn't really need that as it survived the fall on with neither on it's maiden flight.The parts are split between "Booster" and "Sustainer" parts. The fins are designed to notch into a ring you put around the body tube. The booster fins should end up flush with the bottom of the booster body tube. The sustainer fins should be 20mm above the bottom of the sustainer tube as the bottom of the sustainer goes INTO the nosecone of the booster.I provided a photo of the inner workings of the booster, but basically it's a 24mm motor tube that transitions to an 18mm body tube that goes up to and through the middle of the boosters nosecone. There are two dividers that go on each side of this 18mm tube to split the inside of the booster into two sections. On one side, drill holes for the escape gasses to go into. On the other side you'll have the recovery system. Make sure the hole for the shock cord in the "SustainerMMtop" part is on the side with the recovery system.To build this rocket you will need:300mm of BT-55 (33mm) body tube for the sustainer200mm of BT-60 (42mm) body tube for the boosterAbout 70mm of BT-20 (18mm) body tube for the sustainer motor mountAbout 70mm of BT-50 (24mm) body tube for the booster motor mountShock cord (I used Kevlar line) for both the booster and sustainerStreamer material for the booster at least, but I'd add it for visibility on the sustainer too.A 12" chute for the sustainer, though it's tough enough to survive a fall on grass without one.The parts listed here.I've provided two OpenRocket (ORK) files. One with both stages and one with just the sustainer so you can run your own simulations.Link to launch video: https://www.youtube.com/watch?v=_p0fG_KFZmg