> The concept of a self-eating rocket engine was first proposed and patented in 1938. However, no autophage engine designs were fired in a controlled manner until a research partnership between Glasgow University and Dnipro National University, Ukraine achieved this milestone in 2018.
Is this true? I've seen many hobby hybrid rockets built in this fashion over the years, for example acrylic tube + oxygen gas. Maybe none of them were ever launched.
Right, but there you're either putting the acrylic in an extra structural tube, or you're using an acrylic tube which is hugely thicker than necessary so you can leave a substantial unburned shell there as the structure.
The outer part which is acting as structure cannot be burned as fuel because it's necessary as structure, and if you let the burn continue too long, it would cause the rocket to fail. When the burn ends, there's a lot of unburned acrylic still there.
This design allows a given piece of tube to first serve as structure, and then later serve as fuel, ostensibly ending the burn having consumed the whole tube with no structure left behind except perhaps a bit stuck in the feed mechanism. That's novel.
Also, I wonder how complex this is going to make the aerodynamic controls. You are losing moment arms between engine and the forward surfaces, if they exist.
Is this true? I've seen many hobby hybrid rockets built in this fashion over the years, for example acrylic tube + oxygen gas. Maybe none of them were ever launched.
https://www.youtube.com/watch?v=VI8gdmjEwKc
It's pretty much the easiest way to do a hybrid rocket.