Scottish university builds first ‘self-eating’ rocket boosting UK’s reputation in the space industry

A Scottish university has developed and tested the first unsupported autophage rocket engine capable of flying beyond the Earth’s atmosphere. 

Built by engineers from the University of Glasgow, the ‘autophage’ - Latin for self-eating - engine uses parts of itself for fuel, enhancing both efficiency and sustainability in rocket propulsion. 

Professor Patrick Harkness, who led the development of the engine, said: “These results are a foundational step on the way to developing a fully functional autophage rocket engine. 

“Those future rockets could have a wide range of applications which would help advance the UK’s ambitions to develop as a key player in the space industry.” 

It uses waste heat from combustion to melt plastic fuselage and feed it into itself as fuel, alongside other regular liquid propellants. 

By consuming the fuselage, the engine named ‘Ouroborous-3’ could help deter space debris - an issue which could hamper future missions. 

Testing showed Ourobourous-3 is capable of stable burn, a requirement in rocket engines, throughout the autophage stage. It also showed the rocket’s burn can be controlled in an on-off pattern and that plastic fuselage supplied up to one-fifth of the total propellant used. 

Harkness added: “A conventional rocket’s structure makes up between five and 12 per cent of its total mass. Our tests show that the Ouroborous-3 can burn a very similar amount of its own structural mass as propellant. If we could make at least some of that mass available for payload instead, it would be a compelling prospect for future rocket designs.” 

The additional fuel would mean rockets could take less propellant in onboard tanks and have more space for payload. Doing so could allow these rockets to take small nanosatellites directly into space rather than sharing space on more expensive conventionally fuelled rockets. 

With support from Kingston University, engineers have now also demonstrated that the plastic fuselage can withstand the forces required to feed it into the engine without buckling (what happens when a load changes the shape of a structural component), which is essential for a viable flight concept. 

Testing will now continue with new funding from the UK Space Agency and the Sciences and Technology Facilities Council (STFC) after it selected the project as one of 23 space technology initiatives to receive a share of a £4m fund. The team has received £290,000 for further pilot testing of the prototype engine. 

Research was formerly supported by the UK Ministry of Defence and the STFC. 

First patented in 1938, it was not until a research partnership between the University of Glasgow and Dnipro National University in Ukraine in 2018, that self-eating engine designs were fired in a controlled manner. 

The team’s paper, titled ‘Investigation of the Operating Parameters and Performance of an Autophage, Hybrid Rocket Propulsion System’ will be presented at the AIAA SciTech Forum in the US, later today. The forum is the world's largest event for aerospace research, development, and technology.