University of Glasgow engineers have built and fired the first unsupported ‘autophage’ rocket engine which consumes parts of its own body for fuel.   The design of the autophage engine - the name comes from the Latin word for ‘self-eating’ - has several potential advantages over conventional rocket designs.   The engine works by using waste heat from combustion to sequentially melt its own plastic fuselage as it fires. The molten plastic is fed into the engine’s combustion chamber as additional fuel to burn alongside its regular liquid propellants.

This means that an autophage vehicle would require less propellant in onboard tanks, and the mass freed up could be allocated to payload instead. The consumption of the fuselage could also help avoid adding to the problem of space debris – discarded waste that orbits the Earth and could hamper future missions.

https://www.gla.ac.uk/news/headline_1033908_en.html

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Rockets are mostly fuel, but they have other components that must be carried into space. This is why they use multiple stages to reduce the excess weight and allow a more efficient flight.

Engineers in Scotland are working on a self-eating rocket engine that consumes part of its body for fuel. The heat from the rocket melts parts of the fuselage, feeding it into the combustion chamber. This reduces its weight and provides more thrust, allowing for greater payloads.

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