Scientists develop new ‘self-eating’ rocket engine

A group of scientists from the UK’s University of Glasgow and Ukraine’s OlesHonchar Dnipro National University are developing a ‘self-eating’ rocket engine that could launch small satellites into space more easily and affordably.

Compared to most current rockets that use tanks to store their propellant during flights, the autophage-powered rockets are efficient and contribute less to the problem of space junk.

A rocket with an autophage engine is capable of consuming its own structure during ascent, thereby making room for more cargo and producing less debris.

The autophage engine ‘eats’ a propellant rod that has solid fuel on the outside and oxidiser inside. The solid fuel is made of a strong plastic, including polyethylene, so the rod is effectively a pipe full of powdered oxidiser.

By driving the propellant rod into a hot engine, the fuel and oxidiser can be vaporised into gases to flood into the combustion chamber.

This process generates thrust and heat required to vaporise the next section of propellant.

Researchers have already built, fired and throttled up and down an ‘autophage’ engine.

They have also demonstrated that the engine can be throttled by altering the speed at which the rod is driven into the engine.

In lab tests, the researchers have so far sustained rocket operations for 60 seconds.

University of Glasgow School of Engineering senior lecturer Dr Patrick Harkness said: “The propellant rod itself would make up the body of the rocket, and as the vehicle climbed the engine would work its way up, consuming the body from base to tip.

“That would mean that the rocket structure would actually be consumed as fuel, so we wouldn’t face the same problems of excessive structural mass.

“We could size the launch vehicles to match our small satellites, and offer more rapid and more targeted access to space.”

Researchers now intend to secure additional funding to investigate how the engine could be integrated into a launch vehicle.