This is footage that we took when Scott Mikus and me where attempting to build a rocket engine in high school. This was the first of two prototypes we created. I am not quite sure what ever happened to the footage of the second prototype. The second version worked MUCH better. We did a better job with our calculations on it and as a result actually got a couple mach triangles once or twice. They also double as excellent flamethrowers if your turn off the oxygen supply.