[Integza] was reading about a World War II-era rocket plane created near the end of the war by the Germans. The Heinkel He-176 wasn’t very practical, but he was intrigued when he read the rocket was cold and combustionless. He did a little research and found the engine was a monopropellent engine using hydrogen peroxide. This led to some interesting experiments and a 3D printed rocket engine, as you can see in the video below.
Usually, liquid-fueled rocket engines have a fuel and an oxidizer that mix and are either ignited or, in a hypergolic rocket, spontaneously combust on contact. With a monopropellent, the thrust comes from a chemical reaction between the propellant — hydrogen peroxide, in this case, and a catalyst.
There’s a common science demonstration that creates a huge volume of foam using common peroxide and a simple catalyst. For a rocket, though, you need concentrated hydrogen peroxide and certain catalysts. For some reason [Integza] tried different catalysts before settling on what the Germans had used, potassium permanganate. That was much more effective.
Since the reaction isn’t hot, this is a rocket where 3D printing on a consumer-grade printer is practical. In particular, he used a resin printer to create nozzles and a guide to properly mix the peroxide and a liquid catalyst.
For this test, the rocket didn’t go anywhere. Strapped to a fixed mount, [Integza] simply injected the materials with a syringe. The results, though, were impressive and we’d love to see an actual flying rocket or aircraft using this system.
This isn’t the first attempt he’s made at hydrogen peroxide rocket print
