Rocket upper stages are commonly made of aluminium but switching to carbon composites lowers cost and could yield two metric tonnes spare payload capacity.

MT Aerospace and ArianeGroup signed contracts with ESA today to develop “Phoebus”, a Prototype of a Highly OptimisEd Black Upper Stage.

Ulrich Scheib, Director Head of Strategy, Business Development and Space Programs at MT Aerospace, Daniel Neuenschwander, ESA Director of Space Transportation and Jean-Christophe Henoux, Vice President Future Programmes at ArianeGroup signed at ESA Headquarters in Paris, France.

This project builds on legacy upper stage technologies and emerging composite cryogenic capabilities.

This low-cost lightweight Phoebus demonstrator introduces carbon composite materials, in particular for the metallic tanks containing the cryogenic propellants such as liquid hydrogen and oxygen, and for other primary and secondary structures.

Composites allow for new architectures and combinations of functions, which are not possible using metallic materials. Further optimising the entire upper stage architecture, refining propellant loading, minimising surplus fuel, application of wireless sensors, and alternative interface techniques, could bring the estimated increase in payload capacity to as much as two metric tonnes in geostationary orbit.