When the Terran 1 launches, it will bring to life Relativity’s biggest project to date, a massive 3D-printed rocket larger than any other 3D-printed object ever created to go to orbit.

Hybrid rocket engines offer perks from both worlds, with simple solid fuel and the ability to throttle down by regulating oxidizer flow. Naturally, [Integza] decided he should try and 3D print one.

[Sam Rogers] and colleagues at [AX Technologies] have been testing and developing a small liquid-fueled rocket engine and successfully used vortex cooling to protect a resin 3D printed combustion ...